{"id":"2df561ff-2e08-58dc-97cc-0e8ff21d4163","stable_key":"08ce9896-9d1c-5bbf-b705-5bfe771091d5:b7-hlcs-lysine-transfer","predicate":"biotinylates","statement":"HLCS transfers the activated biotin moiety to the epsilon-amino group of a specific lysine in a carboxylase biotin-acceptor domain.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"d37218da-6679-5220-9abb-a5efd2a088e7","mechanism_event_label":"Biotin becomes a tethered part of the enzyme; free lysine and enzyme-bound lysine are different entities.","subject":{"id":"518c7af6-7e78-59ed-a9cb-3de53c9a39c8","slug":"hlcs","display_name":"Human holocarboxylase synthetase / HLCS","entity_type_key":"protein"},"object":{"id":"44399a64-dd8a-5818-a863-b3389c6adf37","slug":"protein-bound-lysine","display_name":"Protein-bound lysine residue","entity_type_key":"protein_state"},"evidence_count":1,"mechanism_event":{"id":"d37218da-6679-5220-9abb-a5efd2a088e7","stable_key":"08ce9896-9d1c-5bbf-b705-5bfe771091d5:b7-hlcs-lysine-transfer-event","event_type":"biochemical_relationship","label":"Biotin becomes a tethered part of the enzyme; free lysine and enzyme-bound lysine are different entities.","description":"HLCS transfers the activated biotin moiety to the epsilon-amino group of a specific lysine in a carboxylase biotin-acceptor domain.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"8356c799-210b-55b0-838b-4ace5fecbffd","slug":"biotinyl-5-amp","display_name":"Biotinyl-5-prime-AMP","entity_type_key":"small_molecule"},"role":"activated donor","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"37a8e96b-f95b-5ba7-a0bc-8ed3cfaf5fd8","slug":"biotin","display_name":"Biotin","entity_type_key":"small_molecule"},"role":"attached cofactor","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"518c7af6-7e78-59ed-a9cb-3de53c9a39c8","slug":"hlcs","display_name":"Human holocarboxylase synthetase / HLCS","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"44399a64-dd8a-5818-a863-b3389c6adf37","slug":"protein-bound-lysine","display_name":"Protein-bound lysine residue","entity_type_key":"protein_state"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/biotin-research/19740736.fulltext.txt\", \"locator\": \"Exact primary full-text span; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"d785655901465bc9798378986d954b87111e3bd73d6877d9d60ae3d95cac0a37\", \"start_char\": 2587, \"end_char\": 3080, \"text_sha256\": \"fa0ec838311a45e8ccebf38a73e340a46417eae6bc300064c1165a4a0b711889\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Purified full-length and residue-58 human HLCS isoforms expressed in E. coli","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Biotin/ATP activation and single-turnover biotin transfer","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Minimal-substrate kinetics do not prove a universal tissue allocation hierarchy; expression host is not the protein species.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Biotin research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"biotin","display_name":"Biotin","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Biotin becomes a tethered part of the enzyme; free lysine and enzyme-bound lysine are different entities.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[b7-p19740736] Distinct amino termini of two human HCS isoforms influence biotin acceptor substrate recognition. (2009). https://pubmed.ncbi.nlm.nih.gov/19740736/ DOI: 10.1074/jbc.m109.046201","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified proteins and minimal biotin-accepting substrate","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"83326305-8723-53c5-9893-6248b92f11e7","evidence_kind":"source_excerpt","locator":"Lines 364-375","start_line":364,"end_line":375,"excerpt":"### b7-hlcs-lysine-transfer\nHLCS transfers the activated biotin moiety to the epsilon-amino group of a specific lysine in a carboxylase biotin-acceptor domain.\nCondition category: normal\nnutrient_topic: Biotin research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Biotin becomes a tethered part of the enzyme; free lysine and enzyme-bound lysine are different entities.\norganism: Homo sapiens\ntissue_or_cell_type: Purified proteins and minimal biotin-accepting substrate\nexperimental_model: Purified full-length and residue-58 human HLCS isoforms expressed in E. coli\nlimitations: Minimal-substrate kinetics do not prove a universal tissue allocation hierarchy; expression host is not the protein species.\nexposure: Biotin/ATP activation and single-turnover biotin transfer\nevidence_span: {\"source_cache\": \"artifacts/biotin-research/19740736.fulltext.txt\", \"locator\": \"Exact primary full-text span; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"d785655901465bc9798378986d954b87111e3bd73d6877d9d60ae3d95cac0a37\", \"start_char\": 2587, \"end_char\": 3080, \"text_sha256\": \"fa0ec838311a45e8ccebf38a73e340a46417eae6bc300064c1165a4a0b711889\"}\n[b7-p19740736] Distinct amino termini of two human HCS isoforms influence biotin acceptor substrate recognition. 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