{"id":"efad411e-7b1e-5316-8e38-7181725cd91f","stable_key":"7edf94bb-95c8-5234-9161-9eb338bb9b36:boron-nad-adduct-structure","predicate":"forms_complex_with","statement":"NAD+ formed monoester, diester and diborate adducts through ribose cis-2,3-diol groups rather than phosphate hydroxyls; the 1:1 monoester localized to the adenosine ribose.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"003c99b1-cba7-5f88-907c-aac925dc7012","mechanism_event_label":"Boron attaches to the sugar portion of NAD+ in these experiments.","subject":{"id":"283ed24b-06a1-50aa-9281-df3bac6ce37e","slug":"nad-plus","display_name":"NAD+","entity_type_key":"small_molecule"},"object":{"id":"a85436e3-2d7b-581a-8a22-13c13fee3248","slug":"borate-nad-plus-complex","display_name":"Boron complex with NAD+","entity_type_key":"chemical_species"},"evidence_count":1,"mechanism_event":{"id":"003c99b1-cba7-5f88-907c-aac925dc7012","stable_key":"7edf94bb-95c8-5234-9161-9eb338bb9b36:boron-nad-adduct-structure-event","event_type":"biochemical_relationship","label":"Boron attaches to the sugar portion of NAD+ in these experiments.","description":"NAD+ formed monoester, diester and diborate adducts through ribose cis-2,3-diol groups rather than phosphate hydroxyls; the 1:1 monoester localized to the adenosine ribose.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"56db2f3c-f247-573f-bb7c-47cac02ea60f","slug":"boric-acid","display_name":"Boric acid / orthoboric acid / B(OH)3","entity_type_key":"small_molecule"},"role":"binding_partner","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"283ed24b-06a1-50aa-9281-df3bac6ce37e","slug":"nad-plus","display_name":"NAD+","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"a85436e3-2d7b-581a-8a22-13c13fee3248","slug":"borate-nad-plus-complex","display_name":"Boron complex with NAD+","entity_type_key":"chemical_species"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/boron-research/12827632.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"a7c91724a5710f61e1907669a1137b421e1e13117ae707e567bd16ca0eea9ed6\", \"start_char\": 0, \"end_char\": 1255, \"text_sha256\": \"a7c91724a5710f61e1907669a1137b421e1e13117ae707e567bd16ca0eea9ed6\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Electrospray mass spectrometry and boron-11 NMR","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"NAD+/NADH with boric acid or borate across pH conditions; complexes detected at 50 µM each at pH 7","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Chemical structure experiments do not establish cellular concentrations or physiological consequences.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Boron research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"boron","display_name":"Boron","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Cell-free chemistry","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Boron attaches to the sugar portion of NAD+ in these experiments.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[boron-p12827632] Esterification of borate with NAD+ and NADH as studied by electrospray ionization mass spectrometry and 11B NMR spectroscopy. (2003). https://pubmed.ncbi.nlm.nih.gov/12827632/ DOI: 10.1002/jms.476","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified nucleotide solutions","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"4118356b-eaa0-5b3c-ae53-7f86c44d891e","evidence_kind":"source_excerpt","locator":"Lines 118-129","start_line":118,"end_line":129,"excerpt":"### boron-nad-adduct-structure\nNAD+ formed monoester, diester and diborate adducts through ribose cis-2,3-diol groups rather than phosphate hydroxyls; the 1:1 monoester localized to the adenosine ribose.\nCondition category: normal\nnutrient_topic: Boron research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Boron attaches to the sugar portion of NAD+ in these experiments.\norganism: Cell-free chemistry\ntissue_or_cell_type: Purified nucleotide solutions\nexperimental_model: Electrospray mass spectrometry and boron-11 NMR\nlimitations: Chemical structure experiments do not establish cellular concentrations or physiological consequences.\nexposure: NAD+/NADH with boric acid or borate across pH conditions; complexes detected at 50 µM each at pH 7\nevidence_span: {\"source_cache\": \"artifacts/boron-research/12827632.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"a7c91724a5710f61e1907669a1137b421e1e13117ae707e567bd16ca0eea9ed6\", \"start_char\": 0, \"end_char\": 1255, \"text_sha256\": \"a7c91724a5710f61e1907669a1137b421e1e13117ae707e567bd16ca0eea9ed6\"}\n[boron-p12827632] Esterification of borate with NAD+ and NADH as studied by electrospray ionization mass spectrometry and 11B NMR spectroscopy. (2003). https://pubmed.ncbi.nlm.nih.gov/12827632/ DOI: 10.1002/jms.476","model_system":"Electrospray mass spectrometry and boron-11 NMR","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [boron-p12827632] Esterification of borate with NAD+ and NADH as studied by electrospray ionization mass spectrometry and 11B NMR spectroscopy. (2003). https://pubmed.ncbi.nlm.nih.gov/12827632/ DOI: 10.1002/jms.476","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"2d96c547-aeec-5d8b-9d31-1288da209f89","stable_key":"import-7edf94bb-95c8-5234-9161-9eb338bb9b36","title":"Boron: chemistry, nutrient interactions, low-intake studies and mechanistic uncertainties (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":"0a32c1c5c70cfb4a378f6ace35cf5b75d90ed3065ada91b9f9f64015d603c8e3","revision_id":"38f316f2-4344-542e-a638-0ac5402f678d","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}