Primary nomenclature entry EC1.17.3.2, Reaction and Comments. Xanthine+water+oxygen yields urate+hydrogen peroxide in the stated overall reaction. Comments also describe superoxide production under some conditions and mammalian dehydrogenase/oxidase interconversion; no claim that peroxide is the only possible oxygen-reduction product.

PNAS69(10),3009–3013(1972), DOI10.1073/pnas.69.10.3009. Original byline R Silber, V G Malathi, J Hurwitz verified; first-author initials retained. Abstract: purified enzyme, ATP/Mg2+ requirement, labelled-end resistance to alkaline phosphatase and exonuclease evidence consistent with intramolecular poly(A) circularization. Distinct from the same-titled1976 article by J. A. Last and W. F. Anderson.

Primary nomenclature entry EC6.5.1.8, accepted name3'-phosphate/5'-hydroxy nucleic acid ligase. Reactions1–2 and Comments: GTP/Mn2+-dependent sealing,3'-phosphate and cyclic-phosphate RNA substrates, enzyme-histidine/guanylate intermediate and productGMP. Card label uses RtcB to avoid a slash in magic links.

Primary nomenclature entry EC6.5.1.3, accepted name RNA ligase(ATP). Reaction and Comments: joining3'-OH and5'-phosphate RNA, ATP consumed to AMP and diphosphate, activated enzyme and RNA intermediates. Institutional classification/reaction record, not a new experiment.

Nucleic Acids Research40(17),8558–8567(2012), DOI10.1093/nar/gks558. Full published title: The sequential2',3'-cyclic phosphodiesterase and3'-phosphate/5'-OH ligation steps of the RtcB RNA splicing pathway are GTP-dependent. Full bylines verified as Anupam K Chakravarty and Stewart Shuman. Abstract and Figures2–3: cyclic-phosphate opening, GTP-dependent ligation and denaturing-PAGE analysis of labelled products; primary full text pmc.ncbi.nlm.nih.gov/articles/PMC3458531/ . Short unique card title avoids a slash in the magic-link argument.

Cell108(5),629–636(2002), DOI10.1016/S0092-8674(02)00649-9. Original abstract/byline verifies full names Hitoshi Nakatogawa and Koreaki Ito; SecM arrest motif and bypass mutations in23S-rRNA/L22 residues facing the tunnel constriction. Publisher corroboration www.sciencedirect.com/science/article/pii/S0092867402006499 .

Nature Communications7,10587(2016); DOI10.1038/ncomms10587. Full primary byline Marina Serna, Joanna L.Giles, B.Paul Morgan, Doryen Bubeck verified. Results: Cryo-EM structure of the MAC; Molecular architecture; Auxiliary domains and MAC assembly; Figure1. Pores assembled on liposomes, functional dye-release check, detergent isolation, frozen-hydrated imaging with direct-electron detection. Reconstructed end product contains18 C9 copies; do not treat this as a universal minimum for lysis.

Journal of Biological Chemistry287(13),10210–10222(2012); DOI10.1074/jbc.M111.327809; primary full text pmc.ncbi.nlm.nih.gov/articles/PMC3323040/ . Introduction and Results: C6 plasma glycoprotein, terminal-complex stoichiometry and full-length C6 crystal structure; proposed assembly model distinguished from directly determined structure. Full primary byline Alexander E.Aleshin verified.

Nature458(2009),1191–1195; DOI10.1038/nature07830. Publisher full first-author byline verifies Beom Seok Park. Abstract and Figures1–3: TLR4–MD-2–LPS crystal structure, hydrophobic pocket in MD-2 and ligand-associated assembly of two receptor-complex units. The study connects ligand recognition with receptor-complex assembly.

Originating curated UDP record. Locators: structure, Formula, Net Charge, IUPAC Name and Ontology. Uridine5′-diphosphate, neutral acid formula C9H14N2O12P2, distinct conjugate-base record CHEBI:58223. The acronym UDP is chemical here; do not create an alias conflicting with the existing network-protocol header.

Science162(3851),361–363(1968); DOI10.1126/science.162.3851.361. Primary Abstract verified in LEVEL015 Goodall preparation: separated guinea-pig C5 fragments, rabbit leukocyte chemotaxis and guinea-pig ileum activity. Current direct PubMed fetch is challenged. Assay species retained; no modern human molecular mass inferred.

Journal of Experimental Medicine122(2),277–298(1965); DOI10.1084/jem.122.2.277; original full text pmc.ncbi.nlm.nih.gov/articles/PMC2138056/ . Primary Abstract verified in LEVEL015 Goodall preparation: isolated beta1F-globulin, kinetic ordering after C3 and dependence of hemolytic function on C6. Current direct PMC fetch is challenged. Initial-only U.R.Nilsson retained.

Originating curated chemical record CHEBI:17985. Definition and structure: adenosine with separate monophosphate groups at ribose positions3′ and5′. Synonyms include adenosine3′,5′-bisphosphate and PAP. Neutral formula C10H15N5O10P2 is a representation, not a claim about predominant physiological charge.

EC2.8.2.17: PAPS-dependent transfer to the6-position of N-acetylgalactosamine in chondroitin; accepted name, Reaction and Comments. Distinct from the other positional sulfotransferase.

EC2.8.2.5: PAPS-dependent transfer to the4-position of N-acetylgalactosamine in chondroitin; accepted name, Reaction and Comments. Distinct from the other positional sulfotransferase.

CHEBI:37397, Definition and ontology: sulfated glycosaminoglycan class, chondroitin functional parent, proteoglycan has-part relation and distinct4/6-sulfated subclasses. Entry checked3November2026; no uniform molecular formula or universal chain-size limit inferred.

Originating curated chemical record CHEBI:17980. Locators: Definition, structure, Formula and Synonyms. Definition specifies adenosine 3′ and 5′ monophosphates with a sulfo group attached to the 5′ phosphate; synonyms identify PAPS and 3′-phosphoadenylyl sulfate. Neutral formula C10H15N5O13P2S; physiological ionization should not be inferred from this neutral representation.

IUPHAR/BPS originating ligand-family record. Locators: C3a human ligand 3640 and C5a human ligand 573, synonym fields identifying both as anaphylatoxins. C5a ligand record www.guidetopharmacology.org/GRAC/LigandDisplayForward?ligandId=573 links C5a to its receptor. Verified for family identity, not numerical potency comparisons.

CHEBI:60312: pyranose form of D-galactosamine, formulaC6H13NO5; CHEBI:148869 separately specifies the alpha anomer. These narrower records do not fix a unique anomer for every use of the broad name galactosamine.

EC2.8.2.8, accepted name and Reaction: PAPS donates to a polymer-associated glucosamine nitrogen, yielding adenosine3′,5′-bisphosphate. The class index still displays the older name desulfoheparin sulfotransferase; the individual entry supplies the current accepted name.