Biochemistry, Department of Chemistry, Philipps-University Marburg, Hans-Meerwein-Strasse D-35043 Marburg, Germany.
J Am Chem Soc. 2011 Mar 30;133(12):4587-95. doi: 10.1021/ja1109453. Epub 2011 Mar 7.
In this work we report the isolation, structural characterization, and the genetic analysis of the biosynthetic origin of rhodochelin, a unique mixed-type catecholate-hydroxamate siderophore isolated from Rhodococcus jostii RHA1. Rhodochelin structural elucidation was accomplished via MS(n)- and NMR-analysis and revealed the tetrapeptide to contain an unusual ester bond between an L-δ-N-formyl-δ-N-hydroxyornithine moiety and the side chain of a threonine residue. Gene deletions within three putative biosynthetic gene clusters abolish rhodochelin production, proving that the ORFs responsible for rhodochelin biosynthesis are located in different chromosomal loci. These results demonstrate the efficient cross-talk between distantly located secondary metabolite gene clusters and outline new insights into the comprehension of natural product biosynthesis.
在这项工作中，我们报告了从 Rhodococcus jostii RHA1 中分离出的独特混合型儿茶酚-羟肟酸盐类铁载体罗地考林的分离、结构特征和生物合成起源的遗传分析。通过 MS(n)-和 NMR 分析完成了罗地考林的结构阐明，结果表明该四肽含有一个不寻常的酯键，连接 L-δ-N-甲酰基-δ-N-羟基鸟氨酸部分和苏氨酸残基的侧链。在三个假定的生物合成基因簇内进行基因缺失会导致罗地考林的产生被完全抑制，这证明了负责罗地考林生物合成的 ORFs 位于不同的染色体位置。这些结果表明了远距离定位的次级代谢物基因簇之间有效的交叉对话，并为理解天然产物生物合成提供了新的见解。
