鲍曼不动杆菌生物膜相关基因研究

Biofilm formation related genes of Acinetobacter baumannii

目的探讨临床分离鲍曼不动杆菌生物膜相关基因的不同生物膜形成能力。方法收集成都医学院第一附属医院2014年1月至2015年1月住院患者临床分离的鲍曼不动杆菌47株,采用结晶紫染色法测定鲍曼不动杆菌的生物膜形成能力。PCR检测abaI、bap、pgaA、pgaB、pgaC、pgaD、csuA/B、csuA、csuB、csuC、csuD、csuE、bfmR、bfmS、pglC、pglL、gacS、H-NS和ompA等19个生物膜相关基因。采用Pearson卡方检验或连续校正卡方检验分析生物被膜形成能力相关基因检出率。结果47株菌株中生物膜形成菌株13株;共检测到17个生物膜相关基因。基因ompA、pgaC、pgaD和bfmR检出率均为100%(47/47),pglL和H-NS检出率均为0(0/47),bap检出率为17.02%(8/47),csuD检出率为53.19%(25/47),其余基因检出率>85%(40/47)。基因bap、pgaB、csuA/B、csuA、csuB和csuD在生物膜阳性菌株中的检出率分别为53.85%、92.31%、100%、100%、92.31%和53.85%,于阴性菌株中检出率分别为2.94%、85.29%、91.18%、97.06%、88.24%和52.94%;csuA/B和csuA在生物膜阳性菌株检出率均为100%,在阴性菌株中检出率分别为91.18%和97.06%。基因bap在生物膜阳性菌株(53.85%、7/13)和阴性菌株的检出率(2.94%、1/34)差异有统计学意义(χ^(2)=13.838、P<0.001),而其他基因在阳性和阴性菌株中检出率差异无统计学意义(P均>0.05)。结论鲍曼不动杆菌生物被膜相关基因bap可能促进生物膜的形成。

Objective To investigate the different biofilm formation ability of clinical isolation of Acinetobacter baumannii(A.baumannii)biofilm related genes.Methods A total of 47 A.baumannii clinical isolates from January 2014 to January 2015 in the First Affiliated Hospital of Chengdu Medical College were collected to analyze the biofilm formation by crystal violet staining assay.The biofilm genes abaI,bap,pgaA,pgaB,pgaC,pgaD,csuA/B,csuA,csuB,csuC,csuD,csuE,bfmR,bfmS,pglC,pglL,gacS,H-NS and ompA were detected by polymerase chain reaction.The clinical isolates biofilm formation ability elated genes were analyzed by Pearson Chi-square to analysis or Chi-square test with continuous correction.Results Thirteen isolates exhibited biofilm formation ability among 47 clinical isolates,and seventeen genes were detected.The detection rates of gene ompA、pgaC、pgaD and bfmR were all 100%(47/47),respectively.The detection rates of pglL and H-NS were both 0(0/47),the ratios of bap and csuD were 17.02%(8/47)and 53.19%(25/47),respectively.The detection rate of other gene was>85%(40/47).The detection rates of gene bap,pgaB,csuA/B,csuA,csuB and csuD were 53.85%,92.31%,100%,100%,92.31%and 53.85%in positive strains,respectively,which were 2.94%,85.29%,91.18%,97.06%,88.24%and 52.94%,respectively in negative strains.The detection rate of csuA/B and csuB were both 100%in positive strains and were 91.18%and 97.06%in negative isolates,respectively.The detection rates of bap gene were significantly different between positive(53.85%,7/13)and negative(2.94%,1/34)strains,with significant difference(χ^(2)=13.838,P<0.001),but there was no significant difference in the detection rates of other genes between positive and negative strains(all P>0.05).Conclusion A.baumannii biofilm related gene bap may promote the ability of biofilm formation.