The Correlation Between Drug Resistance And Some Drug Resistance Genes In Sixty-one Gallibacterium Anatis Isolates

In this research,the drug- 61 Gallibacterium anatis isolates was investigated, and based on it the partial resistance genes were examined by PCR.Meanwhile,the relationship between the phenotype and the genotype was analyzed.Forteen antibiotics were investigated for the sensitivity of 61 Gallibacterium anatis by K-B method.As a result,the strains tested were resistant to Ciprofloxacin,Clindamycin,Laevomycetin,Norfloxacin,Kanamycin,Phytomycin, susceptible to Gentamicin,Tobramycin,Ceftriaxone,Cefepime,Rifampicin,and the percent was 83.61%(51/61),93.44% (57/61),86.89%(53/61),93.44%(57/61),80.33%(49/61),88.52%(54/61),78.69%(48/61),55.74%(34/61),70.49%(43/61),80.33%(49/61),60.66%(37/61),respectively.Multiple drug resistance is very serious, and the most strains were resistant to seven,eight,nine or ten antibiotics with a percent 73.77%(45/61) and 8.2%(5/61) of strains were resistant to more than eleven antibiotics.One strain was resistant to all antibiotics tested.The genes aphA,aadB,aac(6')-Ih,aac(3)-Ia,aac(3)-Ⅱa about Kanamycin were investigated in 61 Gallibacterium anatis by PCR.As a result,only aphA,aadB,aac(3)-Ⅱa were positive,and the detection rate in all strains were 77.05%(47/61),31.15%(19/61),14.75%(9/61),respectively.The percentage of isolates in 49 strains resistant to Kanamycin was 89.80%(44/49),36.73%(18/49),18.37%(9/49), respectively.The positive detection rate of gene aphA was more than that of the other two.So,the gene aphA was considered as the main gene for the resistance to Kanamycin in Gallibacterium anatis.The integrase genes intI1,intI2 and intI3 were investigated in 61 Gallibacterium anatis isolates by PCR.The result indicated that only intI1 was positive,and the detection rate was 31.15% (19/61).The sequence was 100% homology with other bacteriums in NCBI, including E.coli,salmonella,pneumonia crayresearch bacteria,BaoShi motionless bacillus,pseudomonas aeruginosa,and so on.The gene intI1 was located in the plasmid of Gallibacterium anatis.All strains were divided into intI1 positive and negative groups.Suscepbility to 14 antibiotics was analyzed by statistic methods,and as a result,except Ceftriaxone,Cefepime,Rifampicin,the drug resistance rate to other 11 antibiotics was higher in intI1 positive group,demonstrating that the strains with intI1 will get drug resistance more easily.The multiple drug resistance was analyzed between intI1 positive and negative groups,and most strains in positive group were resistance to more than eight antibiotics,but less than five antibiotics in negative group.The integron gene cassettes were investigated in 19 Gallibacterium anatis with intI1 by PCR,18 were positive,and 5 type gene cassettes were found,their size were over 3000 bp,1821bp,1600bp,1007bp,744bp.4 gene cassettes containing resistance genes aadB-PSE-1,aadB-aadA1,aadA2,aadB,respectively.They determined the resistance to Kanamycin,β-lactam antibiotics,Phytomycin and Spectinomycin.But gene cassettes over 3000 bp was not sequenced.