PubMed:26260787 JSONTXT

{"project":"sentences","denotations":[{"id":"T1","span":{"begin":0,"end":107},"obj":"Sentence"},{"id":"T2","span":{"begin":108,"end":334},"obj":"Sentence"},{"id":"T3","span":{"begin":335,"end":496},"obj":"Sentence"},{"id":"T4","span":{"begin":497,"end":710},"obj":"Sentence"},{"id":"T5","span":{"begin":711,"end":833},"obj":"Sentence"},{"id":"T6","span":{"begin":834,"end":964},"obj":"Sentence"},{"id":"T7","span":{"begin":965,"end":1081},"obj":"Sentence"},{"id":"T8","span":{"begin":1082,"end":1358},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"Coq6 is responsible for the C4-deamination reaction in coenzyme Q biosynthesis in Saccharomyces cerevisiae.\nThe yeast Saccharomyces cerevisiae is able to use para-aminobenzoic acid (pABA) in addition to 4-hydroxybenzoic acid as a precursor of coenzyme Q, a redox lipid essential to the function of the mitochondrial respiratory chain. The biosynthesis of coenzyme Q from pABA requires a deamination reaction at position C4 of the benzene ring to substitute the amino group with an hydroxyl group. We show here that the FAD-dependent monooxygenase Coq6, which is known to hydroxylate position C5, also deaminates position C4 in a reaction implicating molecular oxygen, as demonstrated with labeling experiments. We identify mutations in Coq6 that abrogate the C4-deamination activity, whereas preserving the C5-hydroxylation activity. Several results support that the deletion of Coq9 impacts Coq6, thus explaining the C4-deamination defect observed in Δcoq9 cells. The vast majority of flavin monooxygenases catalyze hydroxylation reactions on a single position of their substrate. Coq6 is thus a rare example of a flavin monooxygenase that is able to act on two different carbon atoms of its C4-aminated substrate, allowing its deamination and ultimately its conversion into coenzyme Q by the other proteins constituting the coenzyme Q biosynthetic pathway."}

{"project":"NCBITAXON","denotations":[{"id":"T1","span":{"begin":82,"end":106},"obj":"OrganismTaxon"},{"id":"T2","span":{"begin":118,"end":142},"obj":"OrganismTaxon"}],"attributes":[{"id":"A1","pred":"db_id","subj":"T1","obj":"4932"},{"id":"A2","pred":"db_id","subj":"T2","obj":"4932"}],"text":"Coq6 is responsible for the C4-deamination reaction in coenzyme Q biosynthesis in Saccharomyces cerevisiae.\nThe yeast Saccharomyces cerevisiae is able to use para-aminobenzoic acid (pABA) in addition to 4-hydroxybenzoic acid as a precursor of coenzyme Q, a redox lipid essential to the function of the mitochondrial respiratory chain. The biosynthesis of coenzyme Q from pABA requires a deamination reaction at position C4 of the benzene ring to substitute the amino group with an hydroxyl group. We show here that the FAD-dependent monooxygenase Coq6, which is known to hydroxylate position C5, also deaminates position C4 in a reaction implicating molecular oxygen, as demonstrated with labeling experiments. We identify mutations in Coq6 that abrogate the C4-deamination activity, whereas preserving the C5-hydroxylation activity. Several results support that the deletion of Coq9 impacts Coq6, thus explaining the C4-deamination defect observed in Δcoq9 cells. The vast majority of flavin monooxygenases catalyze hydroxylation reactions on a single position of their substrate. Coq6 is thus a rare example of a flavin monooxygenase that is able to act on two different carbon atoms of its C4-aminated substrate, allowing its deamination and ultimately its conversion into coenzyme Q by the other proteins constituting the coenzyme Q biosynthetic pathway."}