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(2025). https://pubmed.ncbi.nlm.nih.gov/41290650/ DOI: 10.1038/s41467-025-65488-3","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Substrate recognition and carbon-dioxide capture","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"c292801e-eac7-52ca-a2b8-6e0c496af379","evidence_kind":"source_excerpt","locator":"Lines 422-433","start_line":422,"end_line":433,"excerpt":"### k2-ggcx-carbon-capture\nCryo-EM structures and biochemical analyses supported a proposed bicarbonate-mediated carbon-dioxide capture model for GGCX.\nCondition category: normal\nnutrient_topic: Vitamin K2 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The added chemical group comes from carbon dioxide; vitamin K supports the reaction rather than supplying the carbon.\norganism: Human GGCX\ntissue_or_cell_type: Substrate recognition and carbon-dioxide capture\nexperimental_model: Cryo-EM, mutagenesis and molecular dynamics\nlimitations: The carbon-capture/proton-transfer sequence is the authors' structural mechanistic model, not a measured human dietary response or an established bicarbonate-supplement interaction.\nexposure: GGCX complexes with vitamin K, clotting-factor substrates and osteocalcin\nevidence_span: {\"source_cache\": \"artifacts/k2-research/41290650.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"0ea90e4c1af519fa0fc3645f4a4f8f0721924797e0eaa44569ff445c4afe19bc\", \"start_char\": 0, \"end_char\": 1177, \"text_sha256\": \"0ea90e4c1af519fa0fc3645f4a4f8f0721924797e0eaa44569ff445c4afe19bc\"}\n[k2-p41290650] Structural insight into bicarbonate-mediated carboxylation by human vitamin K-dependent carboxylase. 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