γ-PGA Hydrolases of Phage Origin in Bacillus subtilis and Other Microbial Genomes.
γ-PGA Hydrolases of Phage Origin in Bacillus subtilis and Other Microbial Genomes.
复制标题
DOI：
10.1371/journal.pone.0130810
复制
发表时间：
2015
期刊：
影响因子：
3.7
通讯作者：
Calvio C
中科院分区：
文献类型：
--
作者：
Mamberti S;Prati P;Cremaschi P;Seppi C;Morelli CF;Galizzi A;Fabbi M;Calvio C
聚-γ-谷氨酸（γ-PGA）是一种工业上感兴趣的聚合物，主要由芽孢杆菌属的成员分泌，其形成能够保护细菌免受吞噬和吞噬的屏障。已知很少有酶降解γ-PGA;其中有噬菌体编码的γ-PGA水解酶PghP。PghP在细菌中的假定作用是通过拆除γ-PGA屏障来确保进入细菌细胞表面。我们确定了四个未注释的B。枯草芽孢杆菌基因通过其编码产物与PghP的相似性而被分离;事实上，这些基因存在于B的原噬菌体元件中。枯草杆菌基因组其中两个的重组产物表现出有效的聚合物降解，证实了序列相似性反映了功能同源性。编码类似γ-PGA水解酶的基因在芽孢杆菌目特异性芽孢杆菌中和许多微生物基因组中被鉴定，而不仅仅属于该目的。还用生物信息学方法研究了γ-PGA生物合成操纵子的分布;发现具有γ-PGA生物合成功能的生物体的列表比预期的要大，并且包括几种致病物种。此外，在非芽孢杆菌目细菌中，预测的γ-PGA水解酶基因优先发现于不具有聚合物生产遗传资产的物种中。我们的研究结果表明，γ-PGA水解酶基因可能通过水平交换而不是通过噬菌体感染在微生物基因组中传播。我们假设，在生产生物提供的富含γ-PGA的自然栖息地中，从γ-PGA释放谷氨酸低聚物的水解酶的可用性可能是正选择下的有益性状。
Poly-γ-glutamate (γ-PGA) is an industrially interesting polymer secreted mainly by members of the class Bacilli which forms a shield able to protect bacteria from phagocytosis and phages. Few enzymes are known to degrade γ-PGA; among them is a phage-encoded γ-PGA hydrolase, PghP. The supposed role of PghP in phages is to ensure access to the surface of bacterial cells by dismantling the γ-PGA barrier. We identified four unannotated B. subtilis genes through similarity of their encoded products to PghP; in fact these genes reside in prophage elements of B. subtilis genome. The recombinant products of two of them demonstrate efficient polymer degradation, confirming that sequence similarity reflects functional homology. Genes encoding similar γ-PGA hydrolases were identified in phages specific for the order Bacillales and in numerous microbial genomes, not only belonging to that order. The distribution of the γ-PGA biosynthesis operon was also investigated with a bioinformatics approach; it was found that the list of organisms endowed with γ-PGA biosynthetic functions is larger than expected and includes several pathogenic species. Moreover in non-Bacillales bacteria the predicted γ-PGA hydrolase genes are preferentially found in species that do not have the genetic asset for polymer production. Our findings suggest that γ-PGA hydrolase genes might have spread across microbial genomes via horizontal exchanges rather than via phage infection. We hypothesize that, in natural habitats rich in γ-PGA supplied by producer organisms, the availability of hydrolases that release glutamate oligomers from γ-PGA might be a beneficial trait under positive selection.
登录
查看更多内容
DOI：
10.1107/s1744309109029881
发表时间：
2009-09-01
影响因子：
0.9
作者：
Fujimoto, Zui;Shiga, Isao;Kimura, Keitarou
通讯作者：
Kimura, Keitarou
影响因子：
14.9
作者：
NCBI Resource Coordinators
通讯作者：
NCBI Resource Coordinators
影响因子：
2.8
作者：
Ashiuchi, Makoto;Nakamura, Hisaaki;Misono, Haruo
通讯作者：
Misono, Haruo
影响因子：
5
作者：
Hezayen, FF;Rehm, BHA;Steinbüchel, A
通讯作者：
Steinbüchel, A
DOI：
10.1107/s1744309110001685
发表时间：
2010-10-01
影响因子：
0.9
作者：
Bateman, Alex;Coggill, Penny;Finn, Robert D.
通讯作者：
Finn, Robert D.