{"gene":"PF3D7_1346700","run_date":"2026-09-08T14:19:06","timeline":{"discoveries":[{"year":2001,"finding":"Gene disruption of p48/45 in P. berghei (Pbs48/45) and P. falciparum (Pfs48/45) demonstrated that P48/45 is essential for male gamete fertility: p48/45-null parasites showed greatly reduced zygote formation due to failure of male gametes to penetrate otherwise-fertile female gametes, while female gamete fertility was unaffected.","method":"Gene disruption (targeted knockout) with mosquito infection assays and mating studies measuring oocyst formation and zygote formation","journal":"Cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean loss-of-function with defined cellular phenotype (male-specific fertility defect), replicated across two Plasmodium species in the same study with rigorous controls","pmids":["11163248"],"is_preprint":false,"attribution":[{"species":"Plasmodium berghei","strain":""},{"species":"Plasmodium falciparum","strain":""}]},{"year":2001,"finding":"P48/45 was demonstrated by direct experiment to be a surface-exposed protein on male and female gametes of Plasmodium falciparum.","method":"Surface localization assay (antibody recognition of surface-exposed antigen on gametes)","journal":"Cell","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — localization established by antibody reactivity in the same gene-disruption study, single lab","pmids":["11163248"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":1993,"finding":"The Pfs48/45 gene encodes a single-copy, non-repetitive protein of 448 amino acids with a putative N-terminal signal peptide and hydrophobic C-terminus (consistent with GPI anchoring). When expressed in the baculovirus-insect cell system, recombinant Pfs48/45 was targeted to and displayed on the insect cell surface in a conformation recognized by transmission-blocking monoclonal antibodies, establishing surface topology.","method":"Gene cloning, baculovirus heterologous expression, surface display confirmed by transmission-blocking monoclonal antibody recognition","journal":"Molecular and biochemical parasitology","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — heterologous expression with functional antibody recognition; single lab, two orthogonal methods (expression + antibody binding)","pmids":["8259133"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":1992,"finding":"P48/45 (the 48/45-kDa doublet) forms a complex with the 230-kDa gamete surface protein (Pfs230) on the surface of P. falciparum gametes. This complex is disrupted by chaotropic agents, extremes of pH, and by antibodies directed against the 230-kDa protein, but not by antibodies against the 48/45-kDa doublet itself. Disulfide bonds within the complex are normally inaccessible unless the antigens are first denatured, indicating that conformational integrity of Pfs230 is required to maintain the complex.","method":"Co-immunoprecipitation/co-complex analysis, chemical disruption with chaotropic agents and pH extremes, antibody-mediated complex disruption, chemical modification of disulfide/sulfhydryl groups, Triton X-114 phase separation","journal":"Molecular and biochemical parasitology","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — multiple orthogonal biochemical dissection methods in a single lab, no reciprocal Co-IP or structural validation","pmids":["1380124"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2006,"finding":"A positive-negative selectable marker system (yFCU) was used to restore the disrupted p48/45 gene in P. berghei back to its original configuration by homologous recombination, confirming that the fertilization defect observed in p48/45-null parasites is directly attributable to loss of P48/45 function and not to off-target disruption effects.","method":"Reverse genetics: gene disruption followed by genotype restoration via negative selection (yFCU/5-fluorocytosine) and homologous recombination; phenotypic reversion confirmed","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic rescue (genotype restoration) with confirmed phenotypic reversion, providing rigorous causal link between p48/45 and the fertilization phenotype","pmids":["16537837"],"is_preprint":false,"attribution":[{"species":"Plasmodium berghei","strain":""}]},{"year":2010,"finding":"Mating studies among P. berghei parasites lacking P230, P48/45, or P47 demonstrated that P48/45 (like P230) is a male fertility factor required for gamete recognition and/or attachment: gametes of p48/45-null mutants are unable to recognise or attach to partner gametes.","method":"Targeted gene disruption, cross-mating experiments, quantification of oocyst formation and gamete attachment","journal":"PLoS pathogens","confidence":"High","confidence_rationale":"Tier 2 / Strong — multi-gene epistasis/mating study with defined attachment phenotype, replicating and extending the 2001 Cell findings with additional genetic controls","pmids":["20386715"],"is_preprint":false,"attribution":[{"species":"Plasmodium berghei","strain":""}]},{"year":2015,"finding":"Hybridization experiments between P. berghei and P. yoelii showed that hybridization reaches high levels when female gametes lack P48/45, demonstrating that P48/45 on the female gamete surface is a key mediator of pre-zygotic reproductive isolation between Plasmodium species.","method":"Cross-species mating experiments using p48/45 gene-disrupted mutants; quantification of hybrid oocyst formation","journal":"Proceedings. Biological sciences","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic loss-of-function with specific phenotypic readout (hybridization frequency), single study","pmids":["25854886"],"is_preprint":false,"attribution":[{"species":"Plasmodium berghei","strain":""},{"species":"Plasmodium yoelii","strain":""}]},{"year":2018,"finding":"The structure of the C-terminal 6C domain of Pfs48/45 was solved by X-ray crystallography in complex with transmission-blocking monoclonal antibody 85RF45.1, revealing that the domain adopts an SRS (SAG1-related-sequence) fold. The antibody recognizes an electronegative surface on this domain with nanomolar affinity. Residues at the binding interface are rarely polymorphic in natural P. falciparum populations.","method":"X-ray crystallography (structure of 6C domain–antibody complex), binding affinity measurement","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structure with defined epitope and affinity measurement, published in peer-reviewed journal","pmids":["30367064"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2018,"finding":"The structure of the C-terminal domain of Pfs48/45 was determined in complex with a potent transmission-blocking antibody, mapping the epitope location on the domain and demonstrating a structural basis for transmission-blocking activity. A panel of monoclonal antibodies with mapped epitopes correlated epitope location with transmission-blocking potency.","method":"Recombinant full-length Pfs48/45 production, monoclonal antibody panel generation, epitope mapping, X-ray crystallography of C-terminal domain–antibody complex, standard membrane feeding assay","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structure plus functional antibody characterization with epitope–activity correlation; two independent structural studies (PMIDs 30367064 and 30237518) converge on the same domain","pmids":["30237518"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2022,"finding":"The full-length structure of Pfs48/45 was determined, showing that its three domains form a dynamic, planar, triangular arrangement. Transmission-blocking and non-blocking antibodies were shown to bind at distinct sites across the molecule, and antibodies binding across multiple domains of Pfs48/45 can be transmission-blocking.","method":"Structural determination of full-length Pfs48/45 (cryo-EM/X-ray), antibody epitope mapping, standard membrane feeding assays","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 1 / Strong — full-length protein structure with functional antibody mapping and transmission-blocking readout in a single peer-reviewed study","pmids":["36153317"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2018,"finding":"Replacement of endogenous pbs48/45 in P. berghei with pvs48/45 (P. vivax P48/45) via homologous recombination produced transgenic parasites that remained fully transmission-competent and developed into infectious sporozoites, while pbs48/45 knockout parasites were completely incapable of mosquito-stage infection. This establishes functional conservation of P48/45 in male gamete fertility across P. berghei and P. vivax.","method":"Homologous recombination gene replacement; RT-PCR and Western blot confirmation of expression; mosquito infection experiments","journal":"mBio","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic complementation (cross-species gene replacement) with functional rescue confirmed by mosquito infection; multiple orthogonal validation methods","pmids":["30181253"],"is_preprint":false,"attribution":[{"species":"Plasmodium berghei","strain":""},{"species":"Plasmodium vivax","strain":""}]},{"year":2018,"finding":"In P. falciparum, P48/45 is retained on the surface of male gametes of PfΔp230p (P230p-null) mutants, confirming that P48/45 surface expression does not depend on P230p.","method":"CRISPR/Cas9 gene disruption of p230p, immunofluorescence/Western confirmation of P48/45 expression in mutant gametes","journal":"Scientific reports","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — localization/expression confirmed in a genetic mutant background as part of a study focused on a different gene; single lab","pmids":["30297725"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2018,"finding":"Full-length Pfs48/45 expressed as a transgene in P. berghei under the msp1 promoter retained conformational integrity (verified by a panel of conformation-specific monoclonal antibodies recognizing distinct Pfs48/45 epitopes), and immunization of mice with these transgenic schizonts induced antibodies with strong transmission-reducing activity against P. falciparum in standard membrane feeding assays.","method":"Transgenic P. berghei expression of Pfs48/45, confirmation by conformation-specific monoclonal antibody panel, standard membrane feeding assay","journal":"Molecular and biochemical parasitology","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — heterologous expression with multi-antibody conformational validation and functional immunogenicity readout; single lab","pmids":["30053393"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""},{"species":"Plasmodium berghei","strain":""}]},{"year":2008,"finding":"A correctly folded C-terminal fragment of Pfs48/45, co-expressed with four periplasmic folding catalysts in E. coli, displayed transmission-blocking (TB) epitopes recognized by TB monoclonal antibodies and elicited functional transmission-blocking antibodies in 90% of immunized mice in standard membrane feeding assays, establishing that properly folded Pfs48/45 carries the critical TB epitopes.","method":"Recombinant protein production (E. coli with folding catalysts), conformational epitope verification by TB monoclonal antibodies, mouse immunization, standard membrane feeding assay","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional immunogenicity with conformational epitope verification; single lab, two orthogonal methods","pmids":["18332422"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"current_model":"P48/45 (PF3D7_1346700) is a GPI-anchored surface protein expressed on male and female gametes of Plasmodium falciparum and related species; it is essential specifically for male gamete fertility by mediating gamete recognition and attachment during fertilization, and it physically associates with Pfs230 in a disulfide-stabilized surface complex. Its three-domain structure adopts an SRS fold, with the C-terminal 6C domain bearing the principal transmission-blocking epitopes recognized by potent neutralizing antibodies."},"narrative":{"mechanistic_narrative":"P48/45 (PF3D7_1346700) is a single-copy, non-repetitive 6-cysteine surface protein of Plasmodium gametes that functions as a male gamete fertility factor during fertilization [PMID:11163248, PMID:8259133]. Targeted disruption of the gene in both P. berghei and P. falciparum abolishes zygote formation because male gametes fail to penetrate otherwise-fertile female gametes, whereas female fertility is unaffected; genotype restoration reverses this defect, establishing a direct causal link between P48/45 and male fertility [PMID:11163248, PMID:16537837]. Mechanistically, P48/45-null male gametes cannot recognise or attach to partner gametes, placing the protein at the gamete recognition/attachment step [PMID:20386715]. The protein is displayed on the surface of male and female gametes and carries a putative N-terminal signal peptide and hydrophobic C-terminus consistent with GPI anchoring [PMID:11163248, PMID:8259133]. On the gamete surface P48/45 forms a disulfide-stabilized complex with the 230-kDa protein Pfs230, whose conformational integrity is required to maintain the association, though P48/45 surface expression itself is independent of P230p [PMID:1380124, PMID:30297725]. Beyond its fertility role, P48/45 on the female gamete surface mediates pre-zygotic reproductive isolation between Plasmodium species [PMID:25854886], and its function is conserved across species, since P. vivax P48/45 can replace the P. berghei ortholog and restore transmission competence [PMID:30181253]. Structurally, the C-terminal 6C domain adopts an SRS (SAG1-related-sequence) fold and, in the context of the full-length triangular three-domain molecule, presents the principal epitopes recognized by potent transmission-blocking antibodies, making P48/45 a leading transmission-blocking vaccine antigen [PMID:30367064, PMID:36153317, PMID:18332422].","teleology":[{"year":1992,"claim":"Before its function was known, the question was how the 48/45-kDa gamete antigen is organized on the parasite surface; the discovery that it forms a disulfide-stabilized complex with the 230-kDa protein established P48/45 as part of a defined surface assembly.","evidence":"Co-complex biochemical dissection with chaotropic agents, pH extremes, antibody disruption, and disulfide/sulfhydryl modification on P. falciparum gametes","pmids":["1380124"],"confidence":"Medium","gaps":["No reciprocal Co-IP or structural validation of the interaction","Stoichiometry and interface residues not defined","Functional consequence of the complex for fertility not tested here"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":1993,"claim":"The molecular identity and topology of the antigen were unknown; cloning and heterologous expression established a 448-aa single-copy protein with signal peptide and hydrophobic C-terminus displayed at the cell surface in a conformation recognized by transmission-blocking antibodies.","evidence":"Gene cloning and baculovirus surface-display expression with transmission-blocking monoclonal antibody recognition","pmids":["8259133"],"confidence":"Medium","gaps":["GPI anchoring inferred from hydrophobic C-terminus, not directly demonstrated","Single lab, heterologous system","Physiological function still unaddressed"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2001,"claim":"Whether P48/45 has a functional role in the parasite life cycle was unknown; gene disruption in two species revealed a specific, non-redundant requirement for male gamete fertility and confirmed surface exposure on both sexes.","evidence":"Targeted knockout in P. berghei and P. falciparum with mating/mosquito infection assays and gamete surface antibody localization","pmids":["11163248"],"confidence":"High","gaps":["Molecular basis of the male-specific defect not resolved","Whether the defect reflects loss of the Pfs230 complex not tested","GPI anchor and localization mechanism not defined"],"attribution":[{"species":"Plasmodium berghei","strain":""},{"species":"Plasmodium falciparum","strain":""}]},{"year":2006,"claim":"The concern that the fertility phenotype might arise from off-target disruption was outstanding; genotype restoration demonstrated the defect is directly attributable to loss of P48/45.","evidence":"yFCU/5-fluorocytosine negative-selection genotype restoration and phenotypic reversion in P. berghei","pmids":["16537837"],"confidence":"High","gaps":["Does not define the molecular step P48/45 acts at","Interacting partners during fertilization not identified"],"attribution":[{"species":"Plasmodium berghei","strain":""}]},{"year":2008,"claim":"It was unclear whether the transmission-blocking epitopes reside on a specific, foldable fragment; a correctly folded C-terminal fragment carrying conformational TB epitopes elicited functional blocking antibodies, localizing the critical epitopes to the folded C-terminus.","evidence":"E. coli expression with periplasmic folding catalysts, TB monoclonal epitope verification, mouse immunization, standard membrane feeding assay","pmids":["18332422"],"confidence":"Medium","gaps":["Atomic-level epitope not defined","Single lab","Contribution of other domains to blocking not addressed"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2010,"claim":"The precise cellular step disrupted in P48/45-null male gametes was unknown; mating and epistasis studies showed the defect lies at gamete recognition/attachment.","evidence":"Targeted disruption and cross-mating with attachment/oocyst quantification in P. berghei","pmids":["20386715"],"confidence":"High","gaps":["Binding partner on the female gamete not identified","Molecular mechanism of recognition not defined"],"attribution":[{"species":"Plasmodium berghei","strain":""}]},{"year":2015,"claim":"Whether P48/45 contributes to species boundaries was untested; female-gamete P48/45 was shown to mediate pre-zygotic reproductive isolation between Plasmodium species.","evidence":"Cross-species mating of p48/45-disrupted mutants with hybridization frequency readout in P. berghei and P. yoelii","pmids":["25854886"],"confidence":"Medium","gaps":["Molecular basis of species-specific recognition not defined","Single study"],"attribution":[{"species":"Plasmodium berghei","strain":""},{"species":"Plasmodium yoelii","strain":""}]},{"year":2018,"claim":"The atomic structure and epitope basis of transmission blocking, functional conservation, and dependence on the Pfs230 complex were open questions; crystallography of the 6C/C-terminal domain revealed an SRS fold bound by nanomolar TB antibodies, cross-species gene replacement showed functional conservation, and P230p-null studies showed P48/45 surface expression is independent of P230p.","evidence":"X-ray crystallography of C-terminal domain-antibody complexes with epitope-potency mapping and SMFA; P. vivax-for-P. berghei gene replacement with mosquito infection; CRISPR p230p disruption with P48/45 expression assays","pmids":["30367064","30237518","30181253","30297725","30053393"],"confidence":"High","gaps":["Full-length architecture and inter-domain arrangement not yet resolved at this point","Structure of the P48/45-Pfs230 complex not determined","In vivo fertilization mechanism at atomic resolution unknown"],"attribution":[{"species":"Plasmodium falciparum","strain":""},{"species":"Plasmodium berghei","strain":""},{"species":"Plasmodium vivax","strain":""}]},{"year":2022,"claim":"How the three domains are arranged and where blocking antibodies engage across the molecule was unresolved; the full-length structure showed a dynamic planar triangular arrangement with blocking and non-blocking antibodies binding distinct sites, including across multiple domains.","evidence":"Full-length structural determination with antibody epitope mapping and standard membrane feeding assays in P. falciparum","pmids":["36153317"],"confidence":"High","gaps":["Structure of the native gamete-surface complex with Pfs230 not resolved","Molecular basis of gamete attachment at atomic level still unknown"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":null,"claim":"The molecular ligand/partner that P48/45 engages on the partner gamete during recognition and attachment, and the structural basis of the P48/45-Pfs230 surface complex, remain unidentified.","evidence":"","pmids":[],"confidence":"High","gaps":["No fertilization-stage binding partner on the female gamete identified","No structure of the native P48/45-Pfs230 complex","Mechanism linking male-gamete attachment failure to loss of P48/45 not defined at molecular resolution"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":["P48/45-Pfs230 disulfide-stabilized gamete surface complex [#3]"],"partners":["PFS230 (230-KDA GAMETE SURFACE PROTEIN) [#3]"],"other_free_text":["448-aa single-copy protein with N-terminal signal peptide and hydrophobic C-terminus consistent with GPI anchoring [#2]","C-terminal 6C domain adopts an SRS (SAG1-related-sequence) fold [#7]","Full-length protein forms a dynamic planar triangular three-domain arrangement [#9]","Bears principal transmission-blocking epitopes recognized by potent neutralizing antibodies; leading transmission-blocking vaccine antigen [#7, #8, #9, #13]","On female gametes mediates pre-zygotic reproductive isolation between Plasmodium species [#6]","Function conserved across species: P. vivax ortholog rescues P. berghei knockout [#10]"]}},"prefetch_data":{},"corpus_meta":[{"pmid":"11163248","id":"PMC_11163248","title":"A central role for P48/45 in malaria parasite male gamete fertility.","date":"2001","source":"Cell","url":"https://pubmed.ncbi.nlm.nih.gov/11163248","citation_count":339,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["P48/45","P48"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"16103357","id":"PMC_16103357","title":"Genetically attenuated, P36p-deficient malarial sporozoites induce protective immunity and apoptosis of infected liver cells.","date":"2005","source":"Proceedings of the National Academy of Sciences of the United States of 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vectors","url":"https://pubmed.ncbi.nlm.nih.gov/26627683","citation_count":14,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["P48/45","P48"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"30581686","id":"PMC_30581686","title":"The Plasmodium knowlesi Pk41 surface protein diversity, natural selection, sub population and geographical clustering: a 6-cysteine protein family member.","date":"2018","source":"PeerJ","url":"https://pubmed.ncbi.nlm.nih.gov/30581686","citation_count":13,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["6-cysteine protein"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"33480416","id":"PMC_33480416","title":"Nanobody generation and structural characterization of Plasmodium falciparum 6-cysteine protein Pf12p.","date":"2021","source":"The Biochemical 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international","url":"https://pubmed.ncbi.nlm.nih.gov/36403748","citation_count":1,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["6-cysteine protein"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"33940529","id":"PMC_33940529","title":"Structural and immunogenicity analysis of reconstructed ancestral and consensus P48/45 for cross-species anti malaria transmission-blocking vaccine.","date":"2021","source":"Computational biology and chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/33940529","citation_count":1,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["6-cysteine protein","P48/45","P48"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":20228,"output_tokens":3906,"usd":0.059637,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":9987,"output_tokens":4089,"usd":0.07608,"stage2_stop_reason":"end_turn"},"total_usd":0.135717,"stage1_batch_id":"msgbatch_011BPjN2BL33F8cJXD1r7V7T","stage2_batch_id":"msgbatch_01Qwg6vP7qxkpL6Gsc7tajsb","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2001,\n      \"finding\": \"Gene disruption of p48/45 in P. berghei (Pbs48/45) and P. falciparum (Pfs48/45) demonstrated that P48/45 is essential for male gamete fertility: p48/45-null parasites showed greatly reduced zygote formation due to failure of male gametes to penetrate otherwise-fertile female gametes, while female gamete fertility was unaffected.\",\n      \"method\": \"Gene disruption (targeted knockout) with mosquito infection assays and mating studies measuring oocyst formation and zygote formation\",\n      \"journal\": \"Cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean loss-of-function with defined cellular phenotype (male-specific fertility defect), replicated across two Plasmodium species in the same study with rigorous controls\",\n      \"pmids\": [\"11163248\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium berghei\", \"strain\": \"\"},\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"P48/45 was demonstrated by direct experiment to be a surface-exposed protein on male and female gametes of Plasmodium falciparum.\",\n      \"method\": \"Surface localization assay (antibody recognition of surface-exposed antigen on gametes)\",\n      \"journal\": \"Cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — localization established by antibody reactivity in the same gene-disruption study, single lab\",\n      \"pmids\": [\"11163248\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 1993,\n      \"finding\": \"The Pfs48/45 gene encodes a single-copy, non-repetitive protein of 448 amino acids with a putative N-terminal signal peptide and hydrophobic C-terminus (consistent with GPI anchoring). When expressed in the baculovirus-insect cell system, recombinant Pfs48/45 was targeted to and displayed on the insect cell surface in a conformation recognized by transmission-blocking monoclonal antibodies, establishing surface topology.\",\n      \"method\": \"Gene cloning, baculovirus heterologous expression, surface display confirmed by transmission-blocking monoclonal antibody recognition\",\n      \"journal\": \"Molecular and biochemical parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — heterologous expression with functional antibody recognition; single lab, two orthogonal methods (expression + antibody binding)\",\n      \"pmids\": [\"8259133\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 1992,\n      \"finding\": \"P48/45 (the 48/45-kDa doublet) forms a complex with the 230-kDa gamete surface protein (Pfs230) on the surface of P. falciparum gametes. This complex is disrupted by chaotropic agents, extremes of pH, and by antibodies directed against the 230-kDa protein, but not by antibodies against the 48/45-kDa doublet itself. Disulfide bonds within the complex are normally inaccessible unless the antigens are first denatured, indicating that conformational integrity of Pfs230 is required to maintain the complex.\",\n      \"method\": \"Co-immunoprecipitation/co-complex analysis, chemical disruption with chaotropic agents and pH extremes, antibody-mediated complex disruption, chemical modification of disulfide/sulfhydryl groups, Triton X-114 phase separation\",\n      \"journal\": \"Molecular and biochemical parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — multiple orthogonal biochemical dissection methods in a single lab, no reciprocal Co-IP or structural validation\",\n      \"pmids\": [\"1380124\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"A positive-negative selectable marker system (yFCU) was used to restore the disrupted p48/45 gene in P. berghei back to its original configuration by homologous recombination, confirming that the fertilization defect observed in p48/45-null parasites is directly attributable to loss of P48/45 function and not to off-target disruption effects.\",\n      \"method\": \"Reverse genetics: gene disruption followed by genotype restoration via negative selection (yFCU/5-fluorocytosine) and homologous recombination; phenotypic reversion confirmed\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic rescue (genotype restoration) with confirmed phenotypic reversion, providing rigorous causal link between p48/45 and the fertilization phenotype\",\n      \"pmids\": [\"16537837\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium berghei\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Mating studies among P. berghei parasites lacking P230, P48/45, or P47 demonstrated that P48/45 (like P230) is a male fertility factor required for gamete recognition and/or attachment: gametes of p48/45-null mutants are unable to recognise or attach to partner gametes.\",\n      \"method\": \"Targeted gene disruption, cross-mating experiments, quantification of oocyst formation and gamete attachment\",\n      \"journal\": \"PLoS pathogens\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multi-gene epistasis/mating study with defined attachment phenotype, replicating and extending the 2001 Cell findings with additional genetic controls\",\n      \"pmids\": [\"20386715\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium berghei\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"Hybridization experiments between P. berghei and P. yoelii showed that hybridization reaches high levels when female gametes lack P48/45, demonstrating that P48/45 on the female gamete surface is a key mediator of pre-zygotic reproductive isolation between Plasmodium species.\",\n      \"method\": \"Cross-species mating experiments using p48/45 gene-disrupted mutants; quantification of hybrid oocyst formation\",\n      \"journal\": \"Proceedings. Biological sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic loss-of-function with specific phenotypic readout (hybridization frequency), single study\",\n      \"pmids\": [\"25854886\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium berghei\", \"strain\": \"\"},\n        {\"species\": \"Plasmodium yoelii\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"The structure of the C-terminal 6C domain of Pfs48/45 was solved by X-ray crystallography in complex with transmission-blocking monoclonal antibody 85RF45.1, revealing that the domain adopts an SRS (SAG1-related-sequence) fold. The antibody recognizes an electronegative surface on this domain with nanomolar affinity. Residues at the binding interface are rarely polymorphic in natural P. falciparum populations.\",\n      \"method\": \"X-ray crystallography (structure of 6C domain–antibody complex), binding affinity measurement\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structure with defined epitope and affinity measurement, published in peer-reviewed journal\",\n      \"pmids\": [\"30367064\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"The structure of the C-terminal domain of Pfs48/45 was determined in complex with a potent transmission-blocking antibody, mapping the epitope location on the domain and demonstrating a structural basis for transmission-blocking activity. A panel of monoclonal antibodies with mapped epitopes correlated epitope location with transmission-blocking potency.\",\n      \"method\": \"Recombinant full-length Pfs48/45 production, monoclonal antibody panel generation, epitope mapping, X-ray crystallography of C-terminal domain–antibody complex, standard membrane feeding assay\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structure plus functional antibody characterization with epitope–activity correlation; two independent structural studies (PMIDs 30367064 and 30237518) converge on the same domain\",\n      \"pmids\": [\"30237518\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"The full-length structure of Pfs48/45 was determined, showing that its three domains form a dynamic, planar, triangular arrangement. Transmission-blocking and non-blocking antibodies were shown to bind at distinct sites across the molecule, and antibodies binding across multiple domains of Pfs48/45 can be transmission-blocking.\",\n      \"method\": \"Structural determination of full-length Pfs48/45 (cryo-EM/X-ray), antibody epitope mapping, standard membrane feeding assays\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — full-length protein structure with functional antibody mapping and transmission-blocking readout in a single peer-reviewed study\",\n      \"pmids\": [\"36153317\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Replacement of endogenous pbs48/45 in P. berghei with pvs48/45 (P. vivax P48/45) via homologous recombination produced transgenic parasites that remained fully transmission-competent and developed into infectious sporozoites, while pbs48/45 knockout parasites were completely incapable of mosquito-stage infection. This establishes functional conservation of P48/45 in male gamete fertility across P. berghei and P. vivax.\",\n      \"method\": \"Homologous recombination gene replacement; RT-PCR and Western blot confirmation of expression; mosquito infection experiments\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic complementation (cross-species gene replacement) with functional rescue confirmed by mosquito infection; multiple orthogonal validation methods\",\n      \"pmids\": [\"30181253\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium berghei\", \"strain\": \"\"},\n        {\"species\": \"Plasmodium vivax\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"In P. falciparum, P48/45 is retained on the surface of male gametes of PfΔp230p (P230p-null) mutants, confirming that P48/45 surface expression does not depend on P230p.\",\n      \"method\": \"CRISPR/Cas9 gene disruption of p230p, immunofluorescence/Western confirmation of P48/45 expression in mutant gametes\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — localization/expression confirmed in a genetic mutant background as part of a study focused on a different gene; single lab\",\n      \"pmids\": [\"30297725\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Full-length Pfs48/45 expressed as a transgene in P. berghei under the msp1 promoter retained conformational integrity (verified by a panel of conformation-specific monoclonal antibodies recognizing distinct Pfs48/45 epitopes), and immunization of mice with these transgenic schizonts induced antibodies with strong transmission-reducing activity against P. falciparum in standard membrane feeding assays.\",\n      \"method\": \"Transgenic P. berghei expression of Pfs48/45, confirmation by conformation-specific monoclonal antibody panel, standard membrane feeding assay\",\n      \"journal\": \"Molecular and biochemical parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — heterologous expression with multi-antibody conformational validation and functional immunogenicity readout; single lab\",\n      \"pmids\": [\"30053393\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"},\n        {\"species\": \"Plasmodium berghei\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"A correctly folded C-terminal fragment of Pfs48/45, co-expressed with four periplasmic folding catalysts in E. coli, displayed transmission-blocking (TB) epitopes recognized by TB monoclonal antibodies and elicited functional transmission-blocking antibodies in 90% of immunized mice in standard membrane feeding assays, establishing that properly folded Pfs48/45 carries the critical TB epitopes.\",\n      \"method\": \"Recombinant protein production (E. coli with folding catalysts), conformational epitope verification by TB monoclonal antibodies, mouse immunization, standard membrane feeding assay\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional immunogenicity with conformational epitope verification; single lab, two orthogonal methods\",\n      \"pmids\": [\"18332422\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    }\n  ],\n  \"current_model\": \"P48/45 (PF3D7_1346700) is a GPI-anchored surface protein expressed on male and female gametes of Plasmodium falciparum and related species; it is essential specifically for male gamete fertility by mediating gamete recognition and attachment during fertilization, and it physically associates with Pfs230 in a disulfide-stabilized surface complex. Its three-domain structure adopts an SRS fold, with the C-terminal 6C domain bearing the principal transmission-blocking epitopes recognized by potent neutralizing antibodies.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"P48/45 (PF3D7_1346700) is a single-copy, non-repetitive 6-cysteine surface protein of Plasmodium gametes that functions as a male gamete fertility factor during fertilization [#0, #2]. Targeted disruption of the gene in both P. berghei and P. falciparum abolishes zygote formation because male gametes fail to penetrate otherwise-fertile female gametes, whereas female fertility is unaffected; genotype restoration reverses this defect, establishing a direct causal link between P48/45 and male fertility [#0, #4]. Mechanistically, P48/45-null male gametes cannot recognise or attach to partner gametes, placing the protein at the gamete recognition/attachment step [#5]. The protein is displayed on the surface of male and female gametes and carries a putative N-terminal signal peptide and hydrophobic C-terminus consistent with GPI anchoring [#1, #2]. On the gamete surface P48/45 forms a disulfide-stabilized complex with the 230-kDa protein Pfs230, whose conformational integrity is required to maintain the association, though P48/45 surface expression itself is independent of P230p [#3, #11]. Beyond its fertility role, P48/45 on the female gamete surface mediates pre-zygotic reproductive isolation between Plasmodium species [#6], and its function is conserved across species, since P. vivax P48/45 can replace the P. berghei ortholog and restore transmission competence [#10]. Structurally, the C-terminal 6C domain adopts an SRS (SAG1-related-sequence) fold and, in the context of the full-length triangular three-domain molecule, presents the principal epitopes recognized by potent transmission-blocking antibodies, making P48/45 a leading transmission-blocking vaccine antigen [#7, #9, #13].\",\n  \"teleology\": [\n    {\n      \"year\": 1992,\n      \"claim\": \"Before its function was known, the question was how the 48/45-kDa gamete antigen is organized on the parasite surface; the discovery that it forms a disulfide-stabilized complex with the 230-kDa protein established P48/45 as part of a defined surface assembly.\",\n      \"evidence\": \"Co-complex biochemical dissection with chaotropic agents, pH extremes, antibody disruption, and disulfide/sulfhydryl modification on P. falciparum gametes\",\n      \"pmids\": [\"1380124\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No reciprocal Co-IP or structural validation of the interaction\", \"Stoichiometry and interface residues not defined\", \"Functional consequence of the complex for fertility not tested here\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 1993,\n      \"claim\": \"The molecular identity and topology of the antigen were unknown; cloning and heterologous expression established a 448-aa single-copy protein with signal peptide and hydrophobic C-terminus displayed at the cell surface in a conformation recognized by transmission-blocking antibodies.\",\n      \"evidence\": \"Gene cloning and baculovirus surface-display expression with transmission-blocking monoclonal antibody recognition\",\n      \"pmids\": [\"8259133\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"GPI anchoring inferred from hydrophobic C-terminus, not directly demonstrated\", \"Single lab, heterologous system\", \"Physiological function still unaddressed\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2001,\n      \"claim\": \"Whether P48/45 has a functional role in the parasite life cycle was unknown; gene disruption in two species revealed a specific, non-redundant requirement for male gamete fertility and confirmed surface exposure on both sexes.\",\n      \"evidence\": \"Targeted knockout in P. berghei and P. falciparum with mating/mosquito infection assays and gamete surface antibody localization\",\n      \"pmids\": [\"11163248\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular basis of the male-specific defect not resolved\", \"Whether the defect reflects loss of the Pfs230 complex not tested\", \"GPI anchor and localization mechanism not defined\"],\n      \"attribution\": [{\"species\": \"Plasmodium berghei\", \"strain\": \"\"}, {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"The concern that the fertility phenotype might arise from off-target disruption was outstanding; genotype restoration demonstrated the defect is directly attributable to loss of P48/45.\",\n      \"evidence\": \"yFCU/5-fluorocytosine negative-selection genotype restoration and phenotypic reversion in P. berghei\",\n      \"pmids\": [\"16537837\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Does not define the molecular step P48/45 acts at\", \"Interacting partners during fertilization not identified\"],\n      \"attribution\": [{\"species\": \"Plasmodium berghei\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"It was unclear whether the transmission-blocking epitopes reside on a specific, foldable fragment; a correctly folded C-terminal fragment carrying conformational TB epitopes elicited functional blocking antibodies, localizing the critical epitopes to the folded C-terminus.\",\n      \"evidence\": \"E. coli expression with periplasmic folding catalysts, TB monoclonal epitope verification, mouse immunization, standard membrane feeding assay\",\n      \"pmids\": [\"18332422\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Atomic-level epitope not defined\", \"Single lab\", \"Contribution of other domains to blocking not addressed\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"The precise cellular step disrupted in P48/45-null male gametes was unknown; mating and epistasis studies showed the defect lies at gamete recognition/attachment.\",\n      \"evidence\": \"Targeted disruption and cross-mating with attachment/oocyst quantification in P. berghei\",\n      \"pmids\": [\"20386715\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Binding partner on the female gamete not identified\", \"Molecular mechanism of recognition not defined\"],\n      \"attribution\": [{\"species\": \"Plasmodium berghei\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Whether P48/45 contributes to species boundaries was untested; female-gamete P48/45 was shown to mediate pre-zygotic reproductive isolation between Plasmodium species.\",\n      \"evidence\": \"Cross-species mating of p48/45-disrupted mutants with hybridization frequency readout in P. berghei and P. yoelii\",\n      \"pmids\": [\"25854886\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular basis of species-specific recognition not defined\", \"Single study\"],\n      \"attribution\": [{\"species\": \"Plasmodium berghei\", \"strain\": \"\"}, {\"species\": \"Plasmodium yoelii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"The atomic structure and epitope basis of transmission blocking, functional conservation, and dependence on the Pfs230 complex were open questions; crystallography of the 6C/C-terminal domain revealed an SRS fold bound by nanomolar TB antibodies, cross-species gene replacement showed functional conservation, and P230p-null studies showed P48/45 surface expression is independent of P230p.\",\n      \"evidence\": \"X-ray crystallography of C-terminal domain-antibody complexes with epitope-potency mapping and SMFA; P. vivax-for-P. berghei gene replacement with mosquito infection; CRISPR p230p disruption with P48/45 expression assays\",\n      \"pmids\": [\"30367064\", \"30237518\", \"30181253\", \"30297725\", \"30053393\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Full-length architecture and inter-domain arrangement not yet resolved at this point\", \"Structure of the P48/45-Pfs230 complex not determined\", \"In vivo fertilization mechanism at atomic resolution unknown\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}, {\"species\": \"Plasmodium berghei\", \"strain\": \"\"}, {\"species\": \"Plasmodium vivax\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"How the three domains are arranged and where blocking antibodies engage across the molecule was unresolved; the full-length structure showed a dynamic planar triangular arrangement with blocking and non-blocking antibodies binding distinct sites, including across multiple domains.\",\n      \"evidence\": \"Full-length structural determination with antibody epitope mapping and standard membrane feeding assays in P. falciparum\",\n      \"pmids\": [\"36153317\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structure of the native gamete-surface complex with Pfs230 not resolved\", \"Molecular basis of gamete attachment at atomic level still unknown\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The molecular ligand/partner that P48/45 engages on the partner gamete during recognition and attachment, and the structural basis of the P48/45-Pfs230 surface complex, remain unidentified.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No fertilization-stage binding partner on the female gamete identified\", \"No structure of the native P48/45-Pfs230 complex\", \"Mechanism linking male-gamete attachment failure to loss of P48/45 not defined at molecular resolution\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005515\", \"supporting_discovery_ids\": [3]},\n      {\"term_id\": \"GO:0035375\", \"supporting_discovery_ids\": [5]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0009986\", \"supporting_discovery_ids\": [1, 2, 11]},\n      {\"term_id\": \"GO:0098552\", \"supporting_discovery_ids\": [1, 2]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0009566\", \"supporting_discovery_ids\": [0, 4, 5]},\n      {\"term_id\": \"GO:0007339\", \"supporting_discovery_ids\": [0, 5]}\n    ],\n    \"complexes\": [\n      \"P48/45-Pfs230 disulfide-stabilized gamete surface complex [#3]\"\n    ],\n    \"partners\": [\n      \"Pfs230 (230-kDa gamete surface protein) [#3]\"\n    ],\n    \"other_free_text\": [\n      \"448-aa single-copy protein with N-terminal signal peptide and hydrophobic C-terminus consistent with GPI anchoring [#2]\",\n      \"C-terminal 6C domain adopts an SRS (SAG1-related-sequence) fold [#7]\",\n      \"Full-length protein forms a dynamic planar triangular three-domain arrangement [#9]\",\n      \"Bears principal transmission-blocking epitopes recognized by potent neutralizing antibodies; leading transmission-blocking vaccine antigen [#7, #8, #9, #13]\",\n      \"On female gametes mediates pre-zygotic reproductive isolation between Plasmodium species [#6]\",\n      \"Function conserved across species: P. vivax ortholog rescues P. berghei knockout [#10]\"\n    ]\n  }\n}","audit_flag":null,"strains":[{"strain":"Pf3D7","gene_id":"PF3D7_1346700","name":null,"product":"6-cysteine protein P48/45","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PbANKA","gene_id":"PBANKA_1359600","name":null,"product":"6-cysteine protein","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PkH","gene_id":"PKNH_1254400","name":null,"product":"6-cysteine protein","uniprot_acc":null,"chromosome":null,"start_pos":null}],"gene_symbol":"","evaluation":null}