[Expression of Class I integrase gene in Acinetobacter baumannii and drug-resistance].
OBJECTIVE
To explore the expression level of class I integrase (intI 1) mRNA in Acinetobacter baumannii from biofilm cells and planktonic cultured cells ,and to analyze the drug-resistance of Class I integron positive strains.


METHODS
Acinetobacter baumannii were collected from hospitals,and Class I integron strains were screened by gene amplification. Total RNA of Class I integron positive strains was extracted, and the intI1 mRNA expression in the bioflim cells and planktonic cultured cells was measured by RT-PCR. Susceptibilities to antibiotics of Class I integron positive strains were also examined.


RESULTS
The intI1 gene mRNA was expressed under 2 conditions, and the mRNA expressed in the biofilm cells was about 4 times higher than that in the planktonic cultured cells. Among the 64 strains of Acinetobacter baumannii, 46 strains were Class I integron positive strains. The antibiotic resistance of intI1 gene cassette-positive strains was higher than that of gene cassette-negative strains.


CONCLUSIONS
The intI1 gene mRNA can be up-regulated in Acinetobacter baumannii biofilm cells.Class I integron plays an important role in drug resistance. It is much easier to capture gene cassettes for bacteria under biofilm condition.
Li
Le
L
Derpartment of Microbiology, Xiangya School of Medicine, Central South University, Changsha 410078, China.
Xia
Zhong-di
ZD
Hu
Zhao-hui
ZH
Zhou
Zhi-quan
ZQ
Li
Hong-tao
HT
D000151:Acinetobacter Infections / Q000382:microbiology; D040981:Acinetobacter baumannii / Q000235:genetics* / Q000302:isolation & purification; D001483:Base Sequence; D018441:Biofilms; D018432:Drug Resistance, Multiple / Q000235:genetics*; D006801:Humans; D019426:Integrases / Q000096:biosynthesis* / Q000235:genetics; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics
D012333:RNA, Messenger; D019426:Integrases; C115006:integron integrase IntI1