Enzymatic conversion of glucose to UDP-4-keto-6-deoxyglucose in Streptomyces spp.
All of the 2,6-dideoxy sugars contained within the structure of chromomycin A3 are derived from D-glucose. Enzyme assays were used to confirm the presence of hexokinase, phosphoglucomutase, UDPG pyrophosphorylase (UDPGP), and UDPG oxidoreductase (UDPGO), all of which are involved in the pathway of glucose activation and conversion into 2,6-dideoxyhexoses during chromomycin biosynthesis. Levels of the four enzymes in Streptomyces spp. cell extracts were correlated with the production of chromomycins. The pathway of sugar activation in Streptomyces spp. involves glucose 6-phosphorylation by hexokinase, isomerization to G-1-P catalyzed by phosphoglucomutase, synthesis of UDPG catalyzed by UDPGP, and formation of UDP-4-keto-6-deoxyglucose by UDPGO.
Division of Medicinal and Natural Products Chemistry and Center for Biocatalysis and Bioprocessing, College of Pharmacy, The University of Iowa, Iowa City, Iowa 52242, USA.
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Liu
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Rosazza
D002240:Carbohydrate Sequence; D014128:Chromomycin A3 / Q000096:biosynthesis / Q000737:chemistry; D002865:Chromomycins / Q000096:biosynthesis* / Q000737:chemistry; D005947:Glucose / Q000031:analogs & derivatives* / Q000378:metabolism*; D006593:Hexokinase / Q000378:metabolism; D007700:Kinetics; D008956:Models, Chemical; D008969:Molecular Sequence Data; D010733:Phosphoglucomutase / Q000378:metabolism; D013302:Streptomyces / Q000378:metabolism*; D005957:UTP-Glucose-1-Phosphate Uridylyltransferase / Q000378:metabolism; D014530:Uridine Diphosphate / Q000031:analogs & derivatives* / Q000378:metabolism; D014533:Uridine Diphosphate Glucose Dehydrogenase / Q000378:metabolism
D002865:Chromomycins; C115446:UDP-4-keto-6-deoxyglucose; D014530:Uridine Diphosphate; D014128:Chromomycin A3; D014533:Uridine Diphosphate Glucose Dehydrogenase; D006593:Hexokinase; D005957:UTP-Glucose-1-Phosphate Uridylyltransferase; D010733:Phosphoglucomutase; D005947:Glucose