{"id":"cedbef63-a330-53ba-8e6e-869f2eb25790","stable_key":"f992b796-377d-53bf-a39b-7e5d41dbe194:b5-met-acyl-acp-isd11-interface","predicate":"binds_in_hydrophobic_core_of","statement":"In the recombinant hybrid NFS1–ISD11–ACP structure, the phosphopantetheine-linked acyl group of E. coli ACP occupies the hydrophobic core of human ISD11.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"cb181f28-d6ee-50e3-9e67-a3c75d4bc376","mechanism_event_label":"The CoA-derived carrier arm holds a fatty-acid chain that helps form the iron–sulfur complex interface.","subject":{"id":"682789f8-f6a2-56cd-80fd-98414e7d04a0","slug":"e-coli-acpp-acylated","display_name":"Escherichia coli acylated phosphopantetheinyl-AcpP","entity_type_key":"protein_state"},"object":{"id":"c78d3c3c-59b9-5192-b7ec-498124752c92","slug":"lyrm4","display_name":"Human ISD11 / LYRM4","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"cb181f28-d6ee-50e3-9e67-a3c75d4bc376","stable_key":"f992b796-377d-53bf-a39b-7e5d41dbe194:b5-met-acyl-acp-isd11-interface-event","event_type":"biochemical_relationship","label":"The CoA-derived carrier arm holds a fatty-acid chain that helps form the iron–sulfur complex interface.","description":"In the recombinant hybrid NFS1–ISD11–ACP structure, the phosphopantetheine-linked acyl group of E. coli ACP occupies the hydrophobic core of human ISD11.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"9838e184-216a-5a26-a8c5-1777b9dd2d90","slug":"nfs1","display_name":"Human cysteine desulfurase / NFS1","entity_type_key":"protein"},"role":"human_catalytic_component","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"6238d82b-cb8d-5477-ab46-db40608715eb","slug":"e-coli-acpp","display_name":"Escherichia coli acyl carrier protein / AcpP","entity_type_key":"protein"},"role":"bacterial_carrier","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"aab78666-4f68-5db2-b86e-a3c6b18ed62d","slug":"phosphopantetheine","display_name":"4′-Phosphopantetheine","entity_type_key":"small_molecule"},"role":"acyl_linker","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"6b656ff5-9532-5da4-8eea-8ca163a48649","slug":"pyridoxal-phosphate","display_name":"PLP","entity_type_key":"small_molecule"},"role":"NFS1_bound_cofactor","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"682789f8-f6a2-56cd-80fd-98414e7d04a0","slug":"e-coli-acpp-acylated","display_name":"Escherichia coli acylated phosphopantetheinyl-AcpP","entity_type_key":"protein_state"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""},{"entity":{"id":"c78d3c3c-59b9-5192-b7ec-498124752c92","slug":"lyrm4","display_name":"Human ISD11 / LYRM4","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":5,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"true","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_location","value_text":"Abstract; primary Results: Identification of the ACP–Lipid–ISD11 Motif","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Hybrid recombinant human NFS1–ISD11 plus native E. coli ACP; X-ray/EM structure","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Coexpression and structural analysis; no nutrient restriction.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"This is not an all-human ACP structure. The bound PLP and acyl-ACP show cofactor coexistence; dietary B6/B5 dependency or repletion was not tested. This experiment does not establish a dietary pantothenate threshold or benefit from B5 supplementation.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Pantothenic acid (vitamin B5) research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"pantothenate","display_name":"Pantothenate (vitamin B5)","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Homo sapiens proteins; Escherichia coli ACP","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The CoA-derived carrier arm holds a fatty-acid chain that helps form the iron–sulfur complex interface.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[b5-met-cory2017] Structure of human Fe-S assembly subcomplex reveals unexpected cysteine desulfurase architecture and acyl-ACP-ISD11 interactions. (2017). https://pubmed.ncbi.nlm.nih.gov/28634302/ DOI: 10.1073/pnas.1702849114","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified recombinant Fe–S assembly subcomplex","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"75e71dce-eb61-5fab-8b2a-a62ace9997f6","evidence_kind":"source_excerpt","locator":"Lines 935-947","start_line":935,"end_line":947,"excerpt":"### b5-met-acyl-acp-isd11-interface\nIn the recombinant hybrid NFS1–ISD11–ACP structure, the phosphopantetheine-linked acyl group of E. coli ACP occupies the hydrophobic core of human ISD11.\nCondition category: normal\nnutrient_topic: Pantothenic acid (vitamin B5) research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The CoA-derived carrier arm holds a fatty-acid chain that helps form the iron–sulfur complex interface.\norganism: Homo sapiens proteins; Escherichia coli ACP\ntissue_or_cell_type: Purified recombinant Fe–S assembly subcomplex\nexperimental_model: Hybrid recombinant human NFS1–ISD11 plus native E. coli ACP; X-ray/EM structure\nlimitations: This is not an all-human ACP structure. The bound PLP and acyl-ACP show cofactor coexistence; dietary B6/B5 dependency or repletion was not tested. This experiment does not establish a dietary pantothenate threshold or benefit from B5 supplementation.\nexposure: Coexpression and structural analysis; no nutrient restriction.\ncross_nutrient: true\nevidence_location: Abstract; primary Results: Identification of the ACP–Lipid–ISD11 Motif\n[b5-met-cory2017] Structure of human Fe-S assembly subcomplex reveals unexpected cysteine desulfurase architecture and acyl-ACP-ISD11 interactions. (2017). https://pubmed.ncbi.nlm.nih.gov/28634302/ DOI: 10.1073/pnas.1702849114","model_system":"Hybrid recombinant human NFS1–ISD11 plus native E. coli ACP; X-ray/EM structure","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [b5-met-cory2017] Structure of human Fe-S assembly subcomplex reveals unexpected cysteine desulfurase architecture and acyl-ACP-ISD11 interactions. (2017). https://pubmed.ncbi.nlm.nih.gov/28634302/ DOI: 10.1073/pnas.1702849114","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"0716b500-dd0b-5425-b9d0-d88bc9c09e86","stable_key":"import-f992b796-377d-53bf-a39b-7e5d41dbe194","title":"Pantothenic acid (vitamin B5): coenzyme A, deficiency and nutrient interactions (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"b5a49f5a2373ca6064c9a4e014e052dad2f6f199a82bb09b26b82b831c36110b","revision_id":"78f3e793-f084-5ee2-8703-b661c4b650bf","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}