Identification of a Napsamycin Biosynthesis Gene Cluster by Genome Mining
Identification of a Napsamycin Biosynthesis Gene Cluster by Genome Mining
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DOI：
10.1002/cbic.201000460
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发表时间：
2011-02-11
期刊：
影响因子：
3.2
通讯作者：
Gust, Bertolt
中科院分区：
文献类型：
--
作者：
Kaysser, Leonard;Tang, Xiaoyu;Gust, Bertolt
Napsamycins是细菌移位酶I（肽聚糖生物合成中的必需酶）的有效抑制剂，并且被分类为尿苷肽抗生素。它们在肽骨架中包含N-甲基二氨基丁酸、脲基、甲硫氨酸和两个非蛋白原性芳族氨基酸残基，所述肽骨架通过不寻常的烯酰胺键与5 ′-氨基-3 ′-脱氧尿苷连接。利用PCR探针从链霉菌DSM 5940中发现的一个推定的尿苷肽生物合成簇中鉴定出萘莎霉素基因簇。roseosporus NRRL 15998的基因组挖掘。注释揭示了29个假设的基因编码的抗性，调控和生物合成的纳帕霉素。基因簇的分析表明，肽的核心结构是组装的非线性非核糖体肽合成酶（NRPS）样机制，涉及几个离散的单或双结构域蛋白。例如，一些基因可以被分配给N-甲基二氨基丁酸的合成，m-酪氨酸的产生和尿嘧啶部分的还原。LC-ESI-MS和MS/MS分析表明，该基因簇在天蓝色链霉菌M1154中的异源表达导致了napsamycins和mureidomycins的产生。萘莎霉素基因簇为详细研究这类结构不寻常的化合物的生物合成提供了分子基础。
Napsamycins are potent inhibitors of bacterial translocase I, an essential enzyme in peptidoglycan biosynthesis, and are classified as uridylpeptide antibiotics. They comprise an N-methyl diaminobutyric acid, an ureido group, a methionine and two non-proteinogenic aromatic amino acid residues in a peptide backbone that is linked to a 5'-amino-3'-deoxyuridine by an unusual enamide bond. The napsamycin gene cluster was identified in Streptomyces sp. DSM5940 by using PCR probes from a putative uridylpeptide biosynthetic cluster found in S. roseosporus NRRL15998 by genome mining. Annotation revealed 29 hypothetical genes encoding for resistance, regulation and biosynthesis of the napsamycins. Analysis of the gene cluster indicated that the peptide core structure is assembled by a nonlinear non-ribosomal peptide synthetase (NRPS)-like mechanism that involves several discrete single or didomain proteins. Some genes could be assigned, for example, to the synthesis of the N-methyl diaminobutyric acid, to the generation of m-tyrosine and to the reduction of the uracil moiety. The heterologous expression of the gene cluster in Streptomyces coelicolor M1154 resulted in the production of napsamycins and mureidomycins as demonstrated by LC-ESI-MS and MS/MS analysis. The napsamycin gene cluster provides a molecular basis for the detailed study of the biosynthesis of this class of structurally unusual compounds.