Marine Biodiscovery Centre, Department of Chemistry, University of Aberdeen, UK.
Chembiochem. 2012 Dec 21;13(18):2683-9. doi: 10.1002/cbic.201200661. Epub 2012 Nov 21.
Cyanobactins, including patellamides, are a group of cyanobacterial post-translationally modified ribosomal cyclic peptides. The final product should in theory be predictable from the sequence of the precursor peptide and the associated tailoring enzymes. Understanding the mechanism and recognition requirements of these enzymes will allow their rational engineering. We have identified three new cyanobactins from a Cyanothece PCC 7425 culture subjected to a heat shock. One of these compounds revealed a novel signature signal for ThcA, the subtilisin-like serine protease that is homologous to the patellamide protease PatA. The crystal structure of the latter and modelling studies allow rationalisation of the recognition determinants for both enzymes, consistent with the ribosomal biosynthetic origin of the new compounds.
蓝细菌环肽，包括晕环肽，是一组蓝细菌翻译后修饰的核糖体环肽。从前体肽序列和相关的修饰酶的角度来看，理论上可以预测最终产物。了解这些酶的作用机制和识别要求将有助于对它们进行合理的工程设计。我们从受到热冲击的 Cyanothece PCC 7425 培养物中鉴定出三种新的蓝细菌环肽。其中一种化合物揭示了 ThcA 的新特征信号， ThcA 是一种类似于枯草杆菌蛋白酶的丝氨酸蛋白酶，与晕环肽蛋白酶 PatA 同源。后者的晶体结构和建模研究允许对两种酶的识别决定因素进行合理化解释，这与新化合物的核糖体生物合成起源一致。
