NUCLEOTIDE-SEQUENCES AND HETEROLOGOUS EXPRESSION OF TCMG AND TCMP, BIOSYNTHETIC GENES FOR TETRACENOMYCIN-C IN STREPTOMYCES-GLAUCESCENS
NUCLEOTIDE-SEQUENCES AND HETEROLOGOUS EXPRESSION OF TCMG AND TCMP, BIOSYNTHETIC GENES FOR TETRACENOMYCIN-C IN STREPTOMYCES-GLAUCESCENS
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DOI：
10.1128/jb.175.12.3876-3886.1993
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发表时间：
1993-06-01
影响因子：
3.2
通讯作者：
HUTCHINSON, CR
中科院分区：
文献类型：
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作者：
DECKER, H;MOTAMEDI, H;HUTCHINSON, CR
淡灰链霉菌ETH 22794（GLA.0）的四环霉素（TCM）C基因簇的tcm III、tcm Ic和tcm VII区域的核苷酸序列揭示了两个基因tcmP和tcmG的存在。推导的产品tcmG类似于黄素蛋白羟化酶中发现的其他几种细菌，而预测的氨基酸序列tcmP是不显着相似的任何已知的蛋白质在现有的数据库。Southern印迹杂交显示在tcm III（tcmG）突变体中约180-bp缺失，在tcm VII（tcmP）突变体中约1，800-bp插入。tcmG和tcmP在变铅青链霉菌中的异源表达以及tcmP在大肠杆菌中的异源表达证实，tcmP编码O-甲基转移酶，催化TCM E的C-9羧基的甲基化以产生TCM A2，并且tcmG负责TCM A2在C-4、C-4a和C-12 a的羟基化以产生TCM C。这是TCM C生物合成的最后两个步骤。
The nucleotide sequence of the tcmIII, tcmIc, and tcmVII region of the tetracenomycin (TCM) C gene cluster of Streptomyces glaucescens ETH 22794 (GLA.0) revealed the presence of two genes, tcmP and tcmG. The deduced product of tcmG resembles flavoprotein hydroxylases found in several other bacteria, whereas the predicted amino acid sequence of tcmP is not significantly similar to those of any known proteins in the available data bases. Southern blot hybridization revealed an approximately 180-bp deletion in a tcmIII (tcmG) mutant and a 1,800-bp insertion in a tcmVII (tcmP) mutant. Heterologous expression of tcmG and tcmP in Streptomyces lividans and tcmP in Escherichia coli established that tcmP encodes an O-methyltransferase, catalyzing the methylation of the C-9 carboxy group of TCM E to yield TCM A2, and that tcmG is responsible for the hydroxylation of TCM A2 at positions C-4, C-4a, and C-12a to give TCM C. These are the final two steps of TCM C biosynthesis.