Volozhantsev Nikolay V, Shpirt Anna M, Kislichkina Angelina A, Shashkov Alexander S, Verevkin Vladimir V, Fursova Nadezhda K, Knirel Yuriy A
State Research Center for Applied Microbiology and Biotechnology, 142279, Obolensk, Moscow Region, Russia.
N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Prospekt 47, 119991, Moscow, Russia.
Res Microbiol. 2020 Mar;171(2):74-79. doi: 10.1016/j.resmic.2019.10.001. Epub 2019 Oct 10.
The Gram-negative opportunistic pathogen Klebsiella pneumoniae is a significant cause of community-acquired and healthcare-associated infections for which multidrug resistance is a concern worldwide. A major virulence determinant of K. pneumoniae is a polysaccharide capsule (CPS) which forms a barrier around the bacterial cell wall, providing protection from environmental pressures and immune responses of eukaryotic organisms. More than 70 chemical capsule structures of serologically typeable K. pneumoniae strains are known. However, there are little data on the CPS structure and cps gene cluster organization of clinical multidrug resistant K. pneumoniae strains. Our investigation of multidrug resistant carbapenemase OXA-48-producing K. pneumoniae strain KPB536 identified a capsular type that was structurally similar to K. pneumoniae K10 but different from any K. pneumoniae CPS reported so far. The content and organization of the cps gene cluster in K. pneumoniae KPB536 also was determined. The catalytic functions of glycosyltransferases coded by the cps_KPB536 gene cluster were assigned by comparison with those responsible for the synthesis of glycoside linkages in the CPSs of K. pneumoniae types K10 and K61.
革兰氏阴性机会致病菌肺炎克雷伯菌是社区获得性感染和医疗保健相关感染的重要病因，其多重耐药性问题在全球范围内备受关注。肺炎克雷伯菌的一个主要毒力决定因素是多糖荚膜（CPS），它在细菌细胞壁周围形成一道屏障，保护细菌免受环境压力和真核生物免疫反应的影响。已知血清型可分型的肺炎克雷伯菌菌株有70多种化学荚膜结构。然而，关于临床多重耐药肺炎克雷伯菌菌株的CPS结构和cps基因簇组织的数据却很少。我们对产多重耐药碳青霉烯酶OXA-48的肺炎克雷伯菌菌株KPB536进行的研究确定了一种荚膜类型，其结构与肺炎克雷伯菌K10相似，但与迄今报道的任何肺炎克雷伯菌CPS都不同。我们还确定了肺炎克雷伯菌KPB536中cps基因簇的内容和组织。通过与负责肺炎克雷伯菌K10和K61型CPS中糖苷键合成的糖基转移酶进行比较，确定了cps_KPB536基因簇编码的糖基转移酶的催化功能。
