细菌基因组序列中ε-聚赖氨酸合成酶的生物信息学识别与分析

In silico identification and analyses of ε-poly-L-lysine synthetases in bacterial genome sequences

摘要:

【目的】ε-聚赖氨酸的合成由ε-聚赖氨酸合成酶(Pls)所控制，考察Pls在细菌中的分布和保守的序列特征。【方法】基于Pls的作用机制，在蛋白序列中识别与底物结合和缩合相关的结构域，以及决定底物特异性的氨基酸残基，进而在已测序基因组中预测Pls。【结果】发现110个已测序的基因组中编码113个预测的Pls，主要分布在放线菌中，也在两株革兰氏阴性菌中被发现。一些亲缘性较高菌株的Pls一致性较高。【结论】Pls在放线菌中可能广泛分布。Pls的腺苷化、巯基化和底物缩合结构域有相对较高的序列保守性，而跨膜结构域和Linker区相对不保守。

Abstract:

[Objective] The biosynthesis of ε-poly-L-lysine is controlled by the ε-poly-L-lysine synthetase. This paper aims to study the distribution and sequence features of Pls. [Methods] Pls proteins were predicted in the completely sequenced genomes via identification of the substrate-recognition and condensation domains and amino acid residues that determine the substrate specificity. [Results] One hundred and thirteen Pls were identified from 110 genomes, mostly distributed in Actinobacteria, with two identified in Gram-negative bacteria. Most Pls from closely related species display a high degree of identity. [Conclusion] Pls may be widely distributed in Actinobacteria. The adenylation, thiolation, and condensation domains of Pls are conserved while the transmembrane domains and linkers show otherwise.