Genetic Evidence for Distinct Functions of Peptidoglycan Endopeptidases in Escherichia coli.
Genetic Evidence for Distinct Functions of Peptidoglycan Endopeptidases in Escherichia coli.
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DOI：
10.3389/fmicb.2020.565767
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发表时间：
2020
影响因子：
5.2
通讯作者：
Lee CR
中科院分区：
文献类型：
--
作者：
Park SH;Kim YJ;Lee HB;Seok YJ;Lee CR
肽聚糖(PG)是细菌外骨骼的重要组成部分，在维持细胞形态和抵抗高膨胀压力下的细胞裂解中起着关键作用。在细菌细胞伸长和分裂过程中，PG的合成和降解必须受到严格的调控。与参与PG合成的酶不同，PG水解酶在包括大肠杆菌在内的许多细菌中显示出高度冗余。在这项研究中，我们证明了PG内肽酶在细胞生长和分裂中具有不同的作用。对缺失七种PG内肽酶之一的突变体的表型分析表明，MepM特异性表型为盐敏感性，MEPS特异性表型为EDTA敏感性。每种表型的互补试验表明，mepM突变体的表型只能通过MepM恢复，而meps突变体的表型可以通过meps或meph、PbpG或MepM的过表达来恢复。这些不同的表型取决于MepM和MEPs的特定定位和特定结构域。最后，根据已鉴定的表型，我们发现MepM和meph与青霉素结合蛋白1a(PBP1a)和PBP1b都有遗传关联，而MEPs和PbpG只与PBP1b有遗传关联。值得注意的是，PBP1a或PBP1b的缺陷出现在mepM突变体的表型上，这表明MepM在PG合成中的重要性。因此，我们的结果表明，每个PG内肽酶在细胞生长和分裂中发挥着不同的作用，这取决于其不同的结构域和细胞定位。
Peptidoglycan (PG) is an essential component of the bacterial exoskeleton that plays a pivotal role in the maintenance of cell shape and resistance to cell lysis under high turgor pressures. The synthesis and degradation of PG must be tightly regulated during bacterial cell elongation and division. Unlike enzymes involved in PG synthesis, PG hydrolases show high redundancy in many bacteria including Escherichia coli. In this study, we showed that PG endopeptidases have distinct roles in cell growth and division. Phenotypic analysis of mutants lacking one of seven PG endopeptidases identified a MepM-specific phenotype, salt sensitivity, and a MepS-specific phenotype, EDTA sensitivity. Complementation test in each phenotype showed that the phenotype of the mepM mutant was restored only by MepM, whereas the phenotype of the mepS mutant was restored by MepS or by overexpression of MepH, PbpG, or MepM. These distinct phenotypes depend on both the specific localizations and specific domains of MepM and MepS. Finally, using the identified phenotypes, we revealed that MepM and MepH were genetically associated with both penicillin-binding protein 1a (PBP1a) and PBP1b, whereas MepS and PbpG were genetically associated with only PBP1b. Notably, a defect in PBP1a or PBP1b phenocopied the mepM mutant, suggesting the importance of MepM on PG synthesis. Therefore, our results indicate that each PG endopeptidase plays a distinct role in cell growth and division, depending on its distinct domains and cellular localizations.
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影响因子：
3.6
作者：
Schaub, Ryan E.;Chan, Yolande A.;Dillard, Joseph P.
通讯作者：
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影响因子：
4.5
作者：
Tsang, Mary-Jane;Yakhnina, Anastasiya A.;Bernhardt, Thomas G.
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影响因子：
64.5
作者：
Paradis-Bleau C;Markovski M;Uehara T;Lupoli TJ;Walker S;Kahne DE;Bernhardt TG
通讯作者：
Bernhardt TG
影响因子：
3.2
作者：
Uehara, Tsuyoshi;Dinh, Thuy;Bernhardt, Thomas G.
通讯作者：
Bernhardt, Thomas G.
DOI：
10.1073/pnas.120163297
发表时间：
2000-06-06
影响因子：
11.1
作者：
Datsenko, KA;Wanner, BL
通讯作者：
Wanner, BL