P-44 デオキシ糖TDP-L-mycaroseの生合成(ポスター発表の部)

概要

論文の詳細を見る
The biosynthetic pathway for mycarose, a 2,6-dideoxy-3-methylhexose found in the antibiotic tylosin produced by Streptomyces fradiae, has an epimerase and ketoreductase which catalyze the last two steps of the pathway and are encoded tylK and tylC2. To verify the postulated functions of these two genes and to establish the sequence of events in the pathway, functional analyses of the proteins encoded by tylK and tylC2 were carried out. The results clearly show that TylK functions as the 5-epimerase and TylC2 functions as the 4-ketoreductase. However, both enzymes exhibit relaxed substrate specificity such that the production of L-mycarose as the sole product of the pathway depends on the absolute specificity of TylC3, a methyltransferase involved in an early step in the pathway. Exploitation of the promiscuous substrate specificity in the late steps of the mycarose pathway could produce new analogs of tylosin as well as other antibiotics containing this sugar.
天然有機化合物討論会の論文
2005-09-15