Identification of BLB resistant genes in some rice varieties for development of high yielding bacterial leaf blight tolerant types

Aim: To identify bacterial leaf blight resistant genes in some rice varieties so that these resistant varieties can be used as a good source of donor for BLB resistant genes in genetic enhancement program.Methodology: A total of sixty-one rice genotypes including resistant and susceptible checks were screened in field condition by artificial inoculation using IX020 strain of Xoo for two years (Kharif 2016 and 2017). These varieties were also genotyped for seven SSR markers tagged with major BLB resistant genes, i.e., Xa4, xa5, xa13 and Xa7. Results: In artificial screening, significant disease development was recorded and the varieties were categorized using disease scoring scale of IRRI, 1996 where seven cultivars exhibited resistance, while twenty-seven were found to be moderately resistant. In genotyping, there was distinct difference in banding position for resistant and susceptible genotypes. Genotypes having resistant disease reaction, carrying BLB resistant genes were identified. Interpretation: Genotypes IR-64, IR-68144-2b-2-2-3-1-127, Ratna, Surjamukhi, Kalinga-2, Azucena and Zheshan-2 expressed bands of RM markers closely linked to Xa4, xa5, xa13 and Xa7 BLB resistant genes and field testing also confirmed resistant host reaction against pathogens.

Mechanism and influencing factors of natural transformation in bacteria / 生物工程学报

Horizontal gene transfer contributes to the spread of antibiotic-resistance cassettes, the distribution of toxin-encoding phages and the transfer of pathogenicity islands. Natural transformation, which is the process of competent cells to uptake free DNA from environment and to recombine this DNA into the chromosome, is a mode of horizontal gene transfer. Natural transformation promotes the spread of antibiotic-resistance cassettes among different bacteria, resulting in the emergence of antibiotic resistant bacteria. The emergence of antibiotic resistant pathogens poses an enormous threat to the treatment of infections. Natural transformation could occur in many bacteria, but the mechanism many be different in different bacteria. Also, the inducer and efficiency of natural transformation in different bacteria are influenced by various factors. This review focuses on the mechanism and influencing factors of natural transformation in bacteria.

Serotype distribution and antimicrobial resistance of Salmonella isolates from retail chicken carcasses in six provinces of China / 中华预防医学杂志

Objective@#To obtain the serotype diversity and antimicrobial resistance of Salmonella isolates recovered from retail chicken carcasses for sale in six regions of China.@*Methods@#From August 2010 to March 2012, each month 20 retail chicken carcasses including freshly slaughtered, chilled and frozen samples were collected from supermarkets and farmer's markets in 7 monitoring sites in Beijing, Jilin province, Inner Mongolia Autonomous, Shanxi province, Jiangsu province and Guangdong province, respectively. Samples were routinely collected for 12 months for each site. 1 680 chicken carcasses were collected in total and 2 629 Salmonella strains were isolated by PCR and biochemical method. Luminex xMAP method and classical slide agglutination method were carried out to determine isolates' serotypes. Minimal inhibitory concentrations (MICs) of 10 classes of antimicrobials including 14 agents were determined using broth micro-dilution method. Mocular methods were used to determine antimicrobial resistance genes of CIP-CTX-CT co-resistant isolates.@*Results@#In all, 2 629 Salmonella isolates, there were 17 seorgroups and 58 serotypes, B and D1 were the dominant serogroups with rates of 34.7% (n=913) and 31.0% (n=815), Enteritidis (30.8%, n=810), Indiana (17.6%, n=463), Infantis (10.6%, n=278) were the top three serovars. We found 224 CIP-CTX co-resistant S. Indiana containing 3 colistin resistant strains, one of them carrying mcr-1 gene and being ESBLs positive, which demonstrated a nine multi drug resistance against 11 antimicrobials tested.@*Conclusion@#These data began to describe the complicated serovar diversity and heavy antimicrobial resistance of Salmonella isolates recovered from retail chicken carcasses in six regions of China. The findings highlight the emergence of ciprofloxacin and cefotaxime co-resistant S. Indiana and also a mcr-1 positive S. Indiana with heavy multi drug resistance.

Mechanisms of carbapenem and fosfomycin resistance in an Escherichia coli strain isolated from bloodstream infection / 中国感染与化疗杂志

Objective This study was designed to determine the mechanisms of carbapenem and fosfomycin resistance in an Escherichia coli strain isolated from bloodstream infection in Huashan Hospital,Shanghai in 2010 and the mode of transmission of resistance genes.Methods The Escherichia coli isolate was characterized by antibiotic susceptibility testing,multilocus sequence typing (MLST),molecular identification of resistance genes,plasmid typing and the resistant genetic environment analysis.Results It was found that the isolate was resistant to carbapenem,fosfomycin and produced extended-spectrum β-1actamases.MLST genotyping showed it belonged to ST46.The carbapenem-resistant gene blaKPC-2 and fosfomycin resistant genefosA3 co-located on the same conjugative plasmid (～ 70 kb).The β-lactamases gene blaTEM and blaCTX-M located on another conjugative plasmid (～ 150 kb).PCR mapping showed that blaKPC-2 gene located in the structure Tn1721-blaKPC-2-Tn3 andfosA3 gene located between two IS26 elements.Conclusions This Escherichia coli strain isolated from bloodstream infection carried multiple antibiotic resistant genes,including blaKPC-2,fosA3,blaTEM,and blaCTX-M.More attention should be paid to the mechanisms of antibiotic resistance and transmission of resistance genes in Escherichia coli isolates for better control of hospital infections.

Antibiotic-resistant genes and multilocus sequencing typing of Pseudomonas aeruginosa / 中国人兽共患病学报

We investigated the antibiotic‐resistant genes and genetic diversity of Pseudomonas aeruginosa from patients in hospital ,the smear samples from hospital and clinic environment ,and from medical staff’ hands respectively in 2011‐2012 in Nanshan District of Shenzhen .Polymerase chain reaction were used to detect the 20 kinds of antibiotic‐resistant genes (TEM , VEB,CARB,OXA,SHV,PER,GES,GTX,SPM,GIM,IMP,VIM,DHA,oprD,Aac(6′)‐Ⅰ ,Aac(6′)‐Ⅱ ,Aac (3′)‐Ⅰ ,A ac(2″)‐Ⅰ ,qacE1‐sull and int‐Ⅰ) .Multilocus sequencing typing was used to analyze the clonal complexes .The 11 kinds resistant genes TEM ,SHV ,IMP ,DHA ,Aac(6′)‐Ⅰ ,Aac(6′)‐Ⅱ ,Aac(3′)‐Ⅰ ,Aac(2″)‐Ⅰ ,qacE1‐sull ,int‐Ⅰand oprD were detected ,for the positive rates respectively ,and which were 8 .1% ,6 .4% ,4 .8% ,9 .7% ,4 .8% ,14 .5% ,9 .7% , 56 .5% ,8 .1% ,and 8 .1% ;the loss rate of oprD gene was 61 .2% .The 19 antibiotic resistance gene profiles existed in 52 Pseudomonas aeruginosa strains .Multilocus sequencing typing found 39 sequence types and 5 clonal complexes in 62 Pseudo‐monas aeruginosa strains ,CC244 and ST856 were dominant .There were some differences of antibiotic resistance gene profiles between different samples ,the Pseudomonas aeruginosa strains from patients carried multiple resistant genes .In our research , the Pseudomonas aeruginosa had the genetic diversity and the dominant clonal complexes existed .

Methicillin-resistant coagulase-negative staphylococci from healthy dogs in Nsukka, Nigeria

The occurrence, resistance phenotype and molecular mechanisms of resistance of methicillin-resistant staphylococci from groin swabs of 109 clinically healthy dogs in Nsukka, Nigeria were investigated. The groin swab samples were cultured on mannitol salt agar supplemented with 10 µgof cloxacillin. Sixteen methicillin-resistant coagulase negative staphylococci (MRCoNS), all harbouring the mecA gene were isolated from 14 (12.8%) of the 109 dogs studied. The MRCoNS isolated were: S. sciuri subspecies rodentium, S. lentus, S. haemolyticus, and S. simulans with S. sciuri subspecies rodentium (62.5%) being the predominant species. Thirteen (81.3%) of the MRCoNS were resistant to tetracycline while 12 (75%) and 10 (62.5%) were resistant to kanamycin and trimthoprim-sulphamethoxazole respectively. None of the isolates was resistant to fusidic acid, linezolid and vancomycin. Thirteen (81.3%) of the MRCoNS were multi-drug resistance (MDR). Other antimicrobial genes detected were: blaZ, tet(K), tet(M), tet(L), erm(B), lnu(A), aacA-aphD, aphA3, str, dfr(G), cat pC221,and cat pC223. Methicillin-resistant staphylococci are common colonizers of healthy dogs in Nigeria with a major species detected being S. sciuri subsp. rodentium.

Isolation of Staphy lococcus aureus from raw milk and its drug resistance analysis / 中国人兽共患病学报

ABSTRACT:To understand the status of contamination and antimicrobial resistance of Staphylococcus aureus (S .aureus) isolated from raw cow milk ,600 samples were collected from five different provinces in China .After isolation and identification of S .aureus from these samples ,157 S .aureus isolates were obtained .Furthermore ,their resistant phenotype and resistant gene were analyzed by MIC detection ,as well as nine drug‐resistance genes determination and analysis .The result revealed that most of the S .aureus isolates contained multiple antibiotic resistant genes ,and all of the isolates were resistant to penicillin . Of 98 .73% isolates were resistant to amoxicillin .Conversely ,all of the isolates were sensitive to enrofloxacin and vancomycin . Moreover ,there were 29 MRSA positive strains among which 22 strains carrying femA gene .In conclusion ,much more atten‐tion should be paid to the drug‐resistance capabilities of field S .aureus isolates in raw cow milk ,and further monitoring of drug resistant S .aureus strains in milk should also be strengthened so as to ensure milk safety .

Probing the evolutionary conserved regions within functional site of drug-resistant target proteins of Staphylococcus aureus: In silico phylogenetic motif profiling approach.

Staphylococcus aureus is one of the major causes of clinical infections and increasing mortality due to multi-drug resistance. In this study, eight drug-resistant genes, beta-lactamase, metallo-beta-lactamase, vanB, mecA, norA, qacA, qacB and qacC of S. aureus strain Mu50 (vancomycin resistant) were studied to predict the evolutionary conserved functional site residues in their protein sequences. It was found that in beta-lactamase, Tyr, Gly, Thr, Asn and in metallo-beta-lactamase, Thr, His, Gly, Leu, Arg and Asp residues were highly conserved. In vanB, Gly, His and Asp residues were highly conserved. Whereas in mecA, His, Val, Phe, Gln, Lys and in norA, Ser, Leu and Ala residues showed conservedness at moderate level. In the multi-drug efflux pump (corresponding to qacA, qacB and qacC), Gly residue was found to be highly conserved. The homology clustering of target proteins through SCI-PHY algorithm and homologues identified through PSI-BLAST were compared to identify the degree of conservation of functional residues. The phylogenetic motifs identified using homologues of target proteins were validated through domain search to locate their site and functionality in the protein sequences. Interactome analysis was performed to understand the possible mode of interaction of target proteins with their functional partners.

Comparison of extended spectrum β-lactamases-producing Escherichia coli with non-ESBLs-producing E.coli: drug-resistance and virulence / 世界急诊医学杂志（英文）

@#BACKGROUND: The virulent factors ofEscherichia coli (E.coli) play an important role in the process of pathopoiesis. The study aimed to compare drug-resistant genes and virulence genes between extended spectrum β-lactamases (ESBLs)-producingE.coli and non-ESBLs-producing E.coli to provide a reference for physicians in management of hospital infection. METHODS: From October 2010 to August 2011, 96 drug-resistant strains ofE.coli isolated were colected from the specimens in Qingdao Municipal Hospital, Qingdao, China. These bacteria strains were divided into a ESBLs-producing group and a non-ESBLs-producing group. Drug sensitivity tests were performed using the Kirby-Bauer (K-B) method. Disinfectant gene, qacEΔ1-sull and 8 virulence genes (CNF2, hlyA, eaeA, VT1, est, bfpA, elt, and CNF1) were tested by polymerase chain reaction (PCR). RESULTS: Among the 96E.coli isolates, the ESBLs-producingE.coli comprised 46 (47.9％) strains and the non-ESBLs-producingE.coli consisted of 50 (52.1％) strains. The detection rates of multiple drug-resistant strain, qacEΔ1-sull, CNF2, hlyA, eaeA,VT1, est, bfpA, elt, and CNF1 in 46 ESBLs-producingE.coli isolates were 89.1％, 76.1％, 6.5％, 69.6％, 69.6％, 89.1％, 10.9％, 26.1％, 8.7％, and 19.6％, respectively. In the non-ESBLs-producingE.coli strains, the positive rates of multiple drug-resistant strain, qacEΔ1-sull, CNF2, hlyA, eaeA, VT1, est, bfpA, elt, and CNF1 were 62.0％, 80.0％, 16.0％, 28.0％, 64.0％, 38.0％, 6.0％, 34.0％, 10.0％, and 24.0％, respectively. The difference in the detection rates of multiple drug-resistant strain, hlyA and VT1 between the ESBLs-producingE.coli strains and the non-ESBLs-producingE.coli strains was statistically significant (P<0.05). CONCLUSION: The positive rate of multiple drug-resistant strains is higher in the ESBLs-producing strains than in the non-ESBLs-producing strains. The expression of some virulence genes hlyA and VT1 varies between the ESBLs-producing strains and the non-ESBLs-producing strains. Increased awareness of clinicians and enhanced testing by laboratories are required to reduce treatment failures and prevent the spread of multiple drug-resistant strains.

Study on the resistance mechanisms of the carbapenems resistant Citrobacter freundii isolates / 中华微生物学和免疫学杂志

ObjectiveTo analyze the homology of Citrobacter freundii strains and detect multidrug resistant genes.MethodsThe minimum inhibition concentration was tested with standard agar dilution method and the the homology of C.freundii strains was measured with pulsed field gel electrophoresis (PFGE) and the PCR was used to perform the drug resistant genes such as β-lactamase,disappearing of outer membrane channel protein.ResultsThe four strains ( No.1,2,4,5 ) showed nineteen banding patterns with PFGE.PCR experiment showed that there were 2 strains (No.1,4) with blaCTX-M,3 strains (No.2,3,5 ) with blaDHA,1 strains(No.3) with blaACT/MIR,and 4 strains(No.1,2,4,5) with blaKPC-2.PCR analysis comfirmed that No.2 and No.4 disappearing of OmpF and No.3 disappearing both of OmpC and OmpF.The expression levels of the chromosomal ampC gene of No.3 isolates was 106.7 times higher than the negative isolates.ConclusionThere is high homology in carbapenem-resistant isolates and the mechanism of drug resistance is complex including blaKPC,AmpC,ESBLs,disappearing of outer membrane channel protein.The spreading of drug resistance result from above genes.

Sequence analysis of plasmid in Klebsiella pneumoniae KF3 / 中华微生物学和免疫学杂志

Objective To study the structures of the plasmids of Klebsiella pneumoniae KF3 at the genome metagenome level througth with whole plasmid DNA sequencing, to analyze the functional genes carried by plasmid and to identify the correlation of resistance and pathogenicity between the plasmids and the host strains. Methods The alkaline lysis method was used to extract plasmids. We constructed the small insert pUC18 library and the large insert Forsmid library, sequenced and used the Phred / Phrap / Consed package to assemble these sequences and gained a complete sequence. The open reading frame(ORFs) were predicted by the Glimmer software and annotated, analyzed the functions of these genes. Results We successfully constructed the pUC18 library and the Fosmid libraries for the plasmid DNA and obtained three circular double-stranded DNA plasmids: pKF3-70 (69 477 bp), pKF3-90 (91 327 bp) and pKF3-147 ( 147 416 bp). There were drug resistant genes, conjugative transfer genes and mobile DNA elements identified on three plasmids. Conclusion The three plasmids of KF3 could be transferred among different strains. It would lead to the dissemination of the resistant genes.

Resistant Mechanism and Strain Relationship of Multi-resistant Pseudomonas aeruginosa / 中华医院感染学杂志

OBJECTIVE To investigate the correlated resistant genes encoding ?-lactamases,aminoglycoside and genetic marker of integron and transposon in multi-resistant Pseudomonas aeruginosa(MRPA) isolated from clinical specimens and study their relationship by phylogenetic analysis.METHODS Twenty-one resistant genes,two integron-Ⅰ genes and one transposon genetic gene were analyzed by PCR and verified by DNA sequencing.Multi-resistant genes cluster analysis was performed by UPGMA.RESULTS The positive rates of CARB,oprD2,aac(3)-Ⅱ,aac(6′)-Ⅱ,ant(2″)-Ⅰ,intⅠ1,qacE△1-sul1 and merA in 20 strains of MRPA were 15%,100%,70%,15%,15%,85%,85% and 85%,respectively,and other genes were negative.It was classfied to three subgroup,by the multi-resistant genes cluster analysis.CONCLUSIONS MRPA isolated from clinical specimens has carried many resistant genes.The deficiency rate of oprD2 gene is very high.The positive rate of genetic mark genes about integron and transposon is very high.It may be the main multi-resistant mechanism of MRPA.Multi-resistant genes cluster analysis shows that there is clone transmission in MRPA and it can induce nosocomial infection prevalence.

Quaternary Ammonium Compounds Resistant Gene of Multiple Drug Resistant Acinetobacter baumannii / 中华医院感染学杂志

OBJECTIVE To investigae the gene resistant to quaternary ammonium compounds of multiple drug resistant Acinetobacter baumannii(MDR-ABA).METHODS The quaternary ammonium compounds qacE?1 gene in 20 MDR-ABA strains were detected by PCR.RESULTS The 20 MDR-ABA strains showed multiple resistance,its sensitivity to imipenm was 65% only.Among twenty strains of MDR-ABA qacE?1 gene were all positive.CONCLUSIONS The results indicate that qacE?1 gene were all carred class 1 integron.The chlorhexidine usage in prevnting hospital infection after surgery should be reevaluated.

Drug-resistant Genes aadA4/5 and aph(3′)-Ⅰ Associated with Aminoglycosides Be Found Existing in Escherichia coli Isolated from ICU / 中华医院感染学杂志

OBJECTIVE To investigate the antibiotics resistance of Escherichia coli(ECO) and distrubtion of aminoglycoside-modifying enzymes and 16S RNA methylase genes in ICU.METHODS The samples of 20 ECO isolates were collected from Dec 2007 to Jun 2008 of patients in ICU.To determine the sensitivity to the 30 antibacterials K-B method was used and aminoglycoside-modifying enzymes and 16S RNA methylase genes were analyzed by polymerase chain reaction(PCR).RESULTS In among the 20 ECO isolates,8 strains carried aac(3)-Ⅱ(40%),3 carried aac(6′)-Ⅰb(15%) and ant(3″)-Ⅰ(15%),1 be found aph(3′)-Ⅰ(10%)and 13 be found aadA4/5 aminoglycoside-modifying enzymes genes,no strain carried 16S RNA methylase genes.CONCLUSIONS aac(3)-Ⅱ、aac(6′)-Ⅰb,ant(3″)-Ⅰ,aph(3′)-Ⅰ and aadA4/5 aminoglycoside-modifying enzymes genes exist in ECO widely,they should be the main cause inducing the high rate of drug-resistance to aminoglycosides.

Drug-resistant Genes in Acinetobacter baumannii and Relative Analysis of Strains / 中华医院感染学杂志

OBJECTIVE To investigate the drug-resistant genes in Acinetobacter baumannii(ABA) isolated from Shaoxing and the relationship among them to supply evidences for tracing the source of epidemiology.METHODS Nineteen drug-resistant genes were detected by PCR in 39 strains of ABA.RESULTS TEM-gene was found positive in 13 strains of ABA(33.3%),OXA-23 group-gene was in 20 strains(51.3%),aac(3)-Ⅰ gene was in 23 strains(64.1%),aac(6′)-Ⅰ gene was in 25 strains(64.1%),ant(3″)-Ⅰ gene was in 29 strains(74.4%) and qacE△1-sul1 gene was in 32 strains(81.2%).The others were not found in all 39 isolates detected.Clonial transmitted phenomenon was existed.CONCLUSIONS The carrier rate of TEM,OXA-23group,aac(3)-Ⅰ,aac(6′)-Ⅰ,ant(3″)-Ⅰ and qacE△1-sul1 genes is high in ABA.ABA can induce clonial transmitted hospital infection.

Drug-resistant Genes Associated with Aminoglycosides in Acinetobacter baumannii Isolated from ICU / 中华医院感染学杂志

OBJECTIVE To investigate the antibiotic resistance of multi-resistant Acinetobacter baumannii(ABA) and distribution of aminoglycoside-modifying enzymes and 16S rRNA methylase genes in ICU in Yinzhou People′s Hospital in Ningbo. METHODS The samples of 20 ABA isolates were collected from Oct 2007 to Jul 2008 in ICU.K-B method was used to determine the sensitivity to 32 antibacterials and the aminoglycoside-modifying enzymes and 16S rRNA methylase genes were analyzed by polymerase chain reaction(PCR). RESULTS From 20 ABA isolates,8 strains carried aminoglycoside-modifying enzymes genes aac(3)-Ⅰ,aac(3)-Ⅱ,aac(6′)-Ⅰb,and ant(3″)-Ⅰ,their positive rate was 10%,15%,30% and 25%,respectively;no strain carried 16S rRNA methylase genes. CONCLUSIONS The antibiotics resistance of A.baumannii is very serious in Yinzhou People′s Hospital in Ningbo.Aminoglycoside-modifying enzymes genes aac(3)-Ⅰ,aac(3)-Ⅱ,aac(6′)-Ⅰb and ant(3″)-Ⅰ exist in multi-resistant A.baumannii widely.They would be the main causes of high drug-resistantce to aminoglycosides.

?-Lactamases associated Genes of Multi-resistant Pseudomonas aeruginosa in Guangzhou / 中华医院感染学杂志

OBJECTIVE To investigate ?-lactamases genes in multi-resistant Pseudomonas aeruginosa in Guangzhou. METHODS We collected 22 P.aeruginosa strains from hospitalized patients,and detected eleven types of ?-lactamases associated genes by PCR. RESULTS CARB,IMP,TEM,VEB and VIM showed positive amplifications with positive proportions were 100.0%,95.5%,77.3%,13.6% and 4.5%,respectively.Other genes such as GIM,SPM,GES,PER,DHA,OXA-10 and SHV showed negative results. CONCLUSIONS The genes CARB and IMP have high positive rate.Different types of ?-lactamases associated genes in P.aeruginosa aften lead to multi-resistance to antibiotics,which bring great difficulties to clinical therapy and hospital infection monitoring.

Resistant Genes Associated with Extended-spectrum ?-Lactamases in Escherichia coli / 中华医院感染学杂志

OBJECTIVE To investigate resistance to antimicrobials and resistant genes associated with ?-lactamases in Escherichia coli isolated from Changzhou district. METHODS Minimum inhibitory concentrations (MIC) of ampicillin,piperacillin,piperacillin/tazobactam,cefotaxime,ceftazidime,cefepime,aztreonam and imipenem were determined by agar dilution. Seventeen resistant genes of E. coli encoding ?-lactamases including TEM and SHV were detected by PCR amplification and sequenced by DNA sequencer. RESULTS The detecting rates of extended-spectrum ?-lactamases in 80 Klebsiella pneumoniae isolates was 46.3%(37/80). Five ?-lactamase resistant genes including TEM,SHV,CTX-M-1group,OXA-1group and DHA in 37 isolates were found,and their rates were 81.1%,78.4%,21.6%,10.8% and 5.4%,respectively. Of 37 strains,at least one ?-lactamase gene was detected in 36 strains. More than two ?-lactamase resistant genes were simultaneously isolated from 24 strains.Furthermore,four ?-lactamase resistant genes were found in one strain.Only one strain wasn't detected out ?-lactamase gene. CONCLUSIONS E. coli has carried various kinds of ?-lactamase resistant genes in Changzhou district,which become the important causes of resistance to ?-lactam antimicrobials.

Resistance Genes of Antibacterial Agents in MRSA and MSSA / 中华医院感染学杂志

OBJECTIVE To investigate the condition of drug-resistant genes in MRSA and MSSA. METHODS The drug-resistant genes mecA,ermA/B/C,aac(6′)/aph(2″),aph(3′)-Ⅲ,ant(4′,4″) and tetM of MRSA and MSSA were detected by polymerase chain reaction(PCR). RESULTS The 5 kinds of drug-resistant genes,such as mecA,ermA/B/C,aac(6′)/aph(2″),(aph(3′)-Ⅲ) and tetM were positive in MRSA. CONCLUSIONS MRSA is a multi-resistant pathogen.

Extended Spectrum ?-Lactamases Genes in Multidrug-resistant Pseudomonas aeruginosa / 中华医院感染学杂志

OBJECTIVE To investigate the situation of prevalence for extended spectrum ?-lactamases(ESBLs)genes in multidrug-resistant Pseudomonas aeruginosa(PA). METHODS Antimicrobial susceptibility test was performed by agar dilution method and 7 kinds of ESBLs genes were detected by PCR methods in 35 strains of PA. RESULTS In 35 strains of PA, the positive rates of genes of TEM, OXA, PER and GES were 51.4%, 42.8%, 31.4%, and 22.9%, respectively, and genes of SHV, VEB, and CTX-M-1 were all negative. CONCLUSIONS This study shows that there are high positive rates of TEM, OXA, PER and GES genes in PA in our hospital. The GES genes in PA are first reported in China.