State Key Lab of New Drug and Pharmaceutical Process, Shanghai Institute of Pharmaceutical Industry, 1320 West Beijing Road, Shanghai, 200040, China.
Biotechnol Lett. 2013 Sep;35(9):1501-8. doi: 10.1007/s10529-013-1233-3. Epub 2013 Jul 27.
Ramoplanin is a lipopeptide antibiotic active against multi-drug-resistant, Gram-positive pathogens. Structurally, it contains a di-mannose moiety attached to the peptide core at Hpg(11). The biosynthetic gene cluster of ramoplanin has already been reported and the assembly of the depsipeptide has been elucidated but the mechanism of transferring sugar moiety to the peptide core remains unclear. Sequence analysis of the biosynthetic gene cluster indicated ramo-orf29 was a mannosyltransferase candidate. To investigate the involvement of ramo-orf29 in ramoplanin biosynthesis, gene inactivation and complementation have been conducted in Actinoplanes sp. ATCC 33076 by homologous recombination. Metabolite analysis revealed that the ramo-orf29 inactivated mutant produced no ramoplanin but the ramoplanin aglycone. Thus, ramo-orf29 codes for the mannosyltransferase in the ramoplanin biosynthesis pathway. This lays the foundation for further exploitation of the ramoplanin mannosyltransferase and aglycone in combinatorial biosynthesis.
雷莫拉宁是一种脂肽抗生素，对多种耐药性革兰氏阳性病原体具有活性。从结构上看，它含有一个二甘露糖部分，通过 Hpg（11）连接到肽核心上。雷莫拉宁的生物合成基因簇已经被报道，并且已经阐明了去肽的组装，但糖部分转移到肽核心的机制仍不清楚。生物合成基因簇的序列分析表明 ramo-orf29 是甘露糖基转移酶的候选基因。为了研究 ramo-orf29 在雷莫拉宁生物合成中的作用，通过同源重组在 Actinoplanes sp. ATCC 33076 中进行了基因失活和互补实验。代谢产物分析表明，ramo-orf29 失活突变体不产生雷莫拉宁，但产生雷莫拉宁糖苷。因此，ramo-orf29 编码雷莫拉宁生物合成途径中的甘露糖基转移酶。这为进一步开发雷莫拉宁甘露糖基转移酶和糖苷在组合生物合成中的应用奠定了基础。
