Grenga Lucia, Gervasi Fabio, Paolozzi Luciano, Scortichini Marco, Ghelardini Patrizia
Dipartimento di Biologia, Università di Roma Tor Vergata, Italy.
Open Microbiol J. 2012;6:45-52. doi: 10.2174/1874285801206010045. Epub 2012 May 25.
The identification and analysis of the Pseudomonas avellanae mismatch repair system (MMR) were performed via sequencing and cloning the mutS and mutL genes and then analyzing the characteristics of the corresponding proteins studying their function and biological role in an E. coli heterologous system. In these studies, the P. avellanae MutS and MutL proteins were shown to localise at the nucleoid level, in a MutS-dependent manner as far as MutL is concerned, and were also able to complement the defect observed in both the mutS and mutL knockout strains of E. coli. In addition, their ability to form both homo and heterodimers between each other was shown by using the prokaryotic two-hybrid assay. Our results represent a first step to elucidate the MMR mechanism in plant pathogenic pseudomonads since the MMR genes were identified in P. syringae pathovars but there was no evidence on their action as effective repair products.
通过对榛假单胞菌错配修复系统（MMR）的mutS和mutL基因进行测序和克隆，然后在大肠杆菌异源系统中分析相应蛋白质的特性、研究其功能和生物学作用，对该系统进行了鉴定和分析。在这些研究中，榛假单胞菌的MutS和MutL蛋白显示定位于类核水平，就MutL而言以MutS依赖的方式定位，并且还能够弥补在大肠杆菌的mutS和mutL基因敲除菌株中观察到的缺陷。此外，通过原核双杂交试验表明它们彼此之间形成同二聚体和异二聚体的能力。我们的结果代表了阐明植物病原假单胞菌中MMR机制的第一步，因为在丁香假单胞菌致病型中已鉴定出MMR基因，但尚无证据表明它们作为有效的修复产物发挥作用。
