Experimental proof for a signal peptidase I like activity in Mycoplasma pneumoniae, but absence of a gene encoding a conserved bacterial type ISPase
Experimental proof for a signal peptidase I like activity in Mycoplasma pneumoniae, but absence of a gene encoding a conserved bacterial type ISPase
复制标题
DOI：
10.1111/j.1742-4658.2005.04710.x
复制
发表时间：
2005-06-01
期刊：
影响因子：
5.4
通讯作者：
Ruppert, T
中科院分区：
文献类型：
--
作者：
Catrein, I;Herrmann, R;Ruppert, T
尽管肺炎支原体的完整基因组序列的注释没有揭示细菌I型信号肽酶（SPase I），但我们通过确定MPN 142的N-末端基因产物P40（以前称为ORF 6基因）的N-末端，实验表明这种活性必须存在于该细菌中。将质谱与特异性磺化蛋白质的游离氨基末端基团的方法相结合，典型信号肽的切割位点位于P40前体蛋白的氨基酸25和26之间。实验结果与计算方法预测的裂解位点一致，为这些理论分析提供了实验证实。
Although the annotation of the complete genome sequence of Mycoplasma pneumoniae did not reveal a bacterial type I signal peptidase (SPase I) we showed experimentally that such an activity must exist in this bacterium, by determining the N-terminus of the N-terminal gene product P40 of MPN142, formerly called ORF6 gene. Combining mass spectrometry with a method for sulfonating specifically the free amino terminal group of proteins, the cleavage site for a typical signal peptide was located between amino acids 25 and 26 of the P40 precursor protein. The experimental results were in agreement with the cleavage site predicted by computational methods providing experimental confirmation for these theoretical analyses.