Identification of MpaA, an amidase in Escherichia coli that hydrolyzes the gamma-D-glutamyl-meso-diaminopimelate bond in murein peptides.
Identification of MpaA, an amidase in Escherichia coli that hydrolyzes the gamma-D-glutamyl-meso-diaminopimelate bond in murein peptides.
复制标题
MpaA 的鉴定，MpaA 是大肠杆菌中的一种酰胺酶，可水解胞壁质肽中的 γ-D-谷氨酰-内消旋-二氨基庚二酸键。
DOI：
10.1128/jb.185.2.679-682.2003
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发表时间：
2003
影响因子：
3.2
通讯作者：
Park,JamesT
中科院分区：
文献类型：
--
作者：
Uehara,Tsuyoshi;Park,JamesT
在大肠杆菌中鉴定出与球形芽孢杆菌ENP1内肽酶同源的MpaA酰胺酶。在多拷贝质粒中表达MpaA的菌株的细胞提取物中，证明了MpaA的酶活性，即水解小鼠三肽-丙酰-γ-d-谷氨酰胺-中-二氨基苯甲酸中的γ-d-谷氨酰胺-二氨基苯甲酸键。AnmpaA mpl（鼠肽连接酶）双突变体在其细胞质中积累了大量的鼠肽三肽，这与MpaA通过肽聚糖生物合成途径的再循环被阻断而降解三肽的前提相一致。
MpaA amidase was identified inEscherichia coliby its amino acid sequence homology with the ENP1 endopeptidase fromBacillus sphaericus. The enzymatic activity of MpaA, i.e., hydrolysis of the γ-d-glutamyl-diaminopimelic acid bond in the murein tripeptidel-alanyl-γ-d-glutamyl-meso-diaminopimelic acid, was demonstrated in the cell extract of a strain expressingmpaAfrom a multicopy plasmid. AnmpaA mpl(murein peptide ligase) double mutant accumulated large amounts of murein tripeptide in its cytoplasm, consistent with the premise that MpaA degrades the tripeptide if its recycling via the peptidoglycan biosynthetic pathway is blocked.