■探讨为什么血清K2型在化脓性肝脓肿(PLA)肺炎克雷伯菌中占稳定份额。
■共有15株来自PLA的K2肺炎克雷伯菌,21K2来自非PLA,从中国收集了来自解放军的31K1。序列分型,分子血清分型,常规PCR,并进行了梅洛内氏菌致死率。共检测到12个毒力基因:peg-344,allS,p-rmpA,p-rmpA2,c-rmpA,FIMH,mrkD,iuca,iron,irp2,entB,和wzi。研究了来自PLA和非PLA的K2肺炎克雷伯菌菌株与K1菌株之间的差异。
■在来自PLA和非PLA的K2菌株之间发现了毒力基因peg-344和iucA的比率的显着差异。后一组也显示比前者更多样化的序列类型。仅发现来自PLA的K1和K2菌株之间的毒力基因allS和irp2存在显着差异。基于血清型以外的同等毒力因子背景,正如G.mellonella致死率证实的,K2菌株比K1更具毒力。在K2菌株中,基因p-rmpA仅给p-rmpA加p-rmpA2带来同等的毒力。
■基于相同的毒力因子背景,除了血清型,肺炎克雷伯菌K2的毒力比PLA的K1强,这为保持稳定的份额提供了生存优势。
UNASSIGNED: To explore why serotype K2 accounts for a stable share in Klebsiella pneumoniae from pyogenic liver abscess (PLA).
UNASSIGNED: Totally 15 K2 K. pneumoniae strains from PLA, 21 K2 from non-PLA, and 31 K1 from PLA were collected from
China. Sequence typing, molecular serotyping, regular PCR, and Galleria mellonella lethality were performed. A total of 12 virulence genes were detected: peg-344, allS, p-rmpA, p-rmpA2, c-rmpA, fimH, mrkD, iucA, iroN, irp2, entB, and wzi. The differences between K2 K. pneumoniae strains from PLA and non-PLA were investigated along with K1 ones.
UNASSIGNED: Significant differences were found between K2 strains from PLA and non-PLA for the rates of virulence genes peg-344 and iucA. The latter group also showed more diverse sequence types than the former. Significant differences were only found for virulence genes allS and irp2 between K1 and K2 strains from PLA. Based on the equal virulence factors backgrounds other than serotypes, K2 strain is more virulent than K1 as G. mellonella lethality confirmed. Gene p-rmpA only brings equal virulence to p-rmpA plus p-rmpA2 in K2 strain.
UNASSIGNED: Based on the same virulence factors backgrounds except serotypes, K2 K. pneumoniae is more virulent than K1 from PLA, which provides a survival advantage to maintain a stable share.