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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":"74a4b1eb-8592-57e5-bd4b-b32d2d501983","evidence_kind":"source_excerpt","locator":"Lines 409-420","start_line":409,"end_line":420,"excerpt":"### k2-ggcx-processivity\nA conserved dipeptide-anchoring mechanism supports repeated glutamate carboxylation while a substrate remains associated with GGCX.\nCondition category: normal\nnutrient_topic: Vitamin K2 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The enzyme can modify several sites on the same protein during one encounter.\norganism: Human GGCX\ntissue_or_cell_type: Substrate recognition and carbon-dioxide capture\nexperimental_model: Cryo-EM, mutagenesis and molecular dynamics\nlimitations: Structural and biochemical model; the proposed bicarbonate proton relay is not a demonstrated benefit of bicarbonate ingestion.\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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