کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1391183 | 983216 | 2013 | 11 صفحه PDF | دانلود رایگان |

SummaryActinorhodin (ACT) produced by Streptomyces coelicolor A3(2) belongs to the benzoisochromanequinone (BIQ) class of antibiotics. ActVA-ORF5, a flavin-dependent monooxygenase (FMO) essential for ACT biosynthesis, forms a two-component enzyme system in combination with a flavin:NADH oxidoreductase, ActVB. The genes for homologous two-component FMOs are found in the biosynthetic gene clusters for two other BIQs, granaticin (GRA) and medermycin (MED), and a closely related antibiotic, alnumycin (ALN). Our functional analysis of these FMOs (ActVA-ORF5, Gra-ORF21, Med-ORF7, and AlnT) in S. coelicolor unambiguously demonstrated that ActVA-ORF5 and Gra-ORF21 are bifunctional and capable of both p-quinone formation at C-6 in the central ring and C-8 hydroxylation in the lateral ring, whereas Med-ORF7 catalyzes only p-quinone formation. No p-quinone formation on a BIQ substrate was observed for AlnT, which is involved in lateral p-quinone formation in ALN.
Graphical AbstractFigure optionsDownload high-quality image (332 K)Download as PowerPoint slideHighlights
► ActVA-ORF5 is a flavin-dependent monooxygenase required for actinorhodin biosynthesis
► ActVA-ORF5 and its three close homologs were functionally dissected
► ActVA-ORF5 and Gra-21 are bifunctional at C-6/C-8, while Med-7 acts only for C-6
► AlnT exhibits different regiospecificity for oxidation of tricyclic substrates
Journal: - Volume 20, Issue 4, 18 April 2013, Pages 510–520