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1.
Deepjyoti Paul Debadatta Dhar Chanda Anand Prakash Maurya Shweta Mishra Atanu Chakravarty Gauri Dutt Sharma Amitabha Bhattacharjee 《PloS one》2015,10(12)
Global spread of KPC poses to be a serious threat complicating treatment options in hospital settings. The present study investigates the genetic environment of bla
KPC-2 among clinical isolates of Pseudomonas aeruginosa from a tertiary referral hospital of India. The study isolates were collected from different wards and clinics of Silchar Medical College and Hospital, India, from 2012–2013. The presence of bla
KPC was confirmed by genotypic characterization followed by sequencing. Cloning of the bla
KPC-2 gene was performed and the genetic environment of this gene was characterized as well. Transferability of the resistance gene was determined by transformation assay and Southern hybridization. Additionally, restriction mapping was also carried out. Two isolates of P. aeruginosa were found to harbor bla
KPC-2, were resistant towards aminoglycosides, quinolone and β-lactam-β-lactamase inhibitor combination. In both the isolates, the resistance determinant was associated with class 1 integron and horizontally transferable. Both the isolates were co-harboring bla
NDM-1. The first detection of this integron mediated bla
KPC-2 coexisting with bla
NDM-1 in P. aeruginosa from India is worrisome, and further investigation is required to track the gene cassette mediated bla
KPC-2 in terms of infection control and to prevent the spread of this gene in hospitals as well as in the community. 相似文献
2.
Background
The current spread of the gene encoding the metallo-ß-lactamase NDM-1 in Enterobacteriaceae is linked to a variety of surrounding genetic structures and plasmid scaffolds.Methodology
The whole sequence of plasmid pGUE-NDM carrying the bla NDM-1 gene was determined by high-density pyrosequencing and a genomic comparative analysis with other bla NDM-1-negative IncFII was performed.Principal Findings
Plasmid pGUE-NDM replicating in Escherichia coli confers resistance to many antibiotic molecules including β-lactams, aminoglycosides, trimethoprim, and sulfonamides. It is 87,022 bp in-size and carries the two β-lactamase genes bla NDM-1 and bla OXA-1, together with three aminoglycoside resistance genes aacA4, aadA2, and aacC2. Comparative analysis of the multidrug resistance locus contained a module encompassing the bla NDM-1 gene that is actually conserved among different structures identified in other enterobacterial isolates. This module was constituted by the bla NDM-1 gene, a fragment of insertion sequence ISAba125 and a bleomycin resistance encoding gene.Significance
This is the first characterized bla NDM-1-carrying IncFII-type plasmid. Such association between the bla NDM-1 gene and an IncFII-type plasmid backbone is extremely worrisome considering that this plasmid type is known to spread efficiently, as examplified with the worldwide dissemination of bla CTX-M-15-borne IncFII plasmids. 相似文献3.
Branko Jovčić Zorica Lepšanović Jelena Begović Brankica Filipić Milan Kojić 《Antonie van Leeuwenhoek》2014,105(3):613-618
New Delhi metallo-β-lactamase producing Pseudomonas aeruginosa isolates are of special interest since P. aeruginosa is a major cause of nosocomial infections, the treatment of which could now be jeopardized, especially in developing countries. Six additional NDM-1 positive P. aeruginosa clinical isolates belonging to two different genotypes were shown to be plasmid-free. PFGE-hybridization experiments revealed the chromosomal location of the bla NDM-1 gene. Restriction analysis and hybridization revealed that two copies of the bla NDM-1 gene are present in the genomes of all tested isolates, as in previously characterized P. aeruginosa MMA83. Moreover, it was shown that increasing imipenem concentration did not have the effect on copy number of the bla NDM-1 gene in the genome of P. aeruginosa MMA83. 相似文献
4.
Background
The prevalence of carbapenem-resistant Acinetobacter baumannii in hospitals has been increasing worldwide. This study aims to investigate the carbapenemase genes and the clonal relatedness among A. baumannii clinical isolates in a Chinese hospital.Methods
Carbapenemase genes and the upstream locations of insertion sequences were detected by polymerase chain reaction (PCR), and the clonal relatedness of isolates was determined by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing.Results
A total of 231 nonduplicate carbapenemase gene-harboring A. baumannii clinical isolates recovered from Shenzhen People’s Hospital, were investigated between 2002 and 2009. bla OXA-23-like, bla OXA-58-like, bla OXA-40-like, and ISAba1-bla OXA-51-like were identified in 119, 107, 1, and 4 isolates, respectively. IS1008-ΔISAba3, ISAba3, and ISAba1 were detected upstream of the bla OXA-58-like gene in 69, 35, and 3 isolates, respectively. All bla OXA-23-like genes but one had an upstream insertion of ISAba1. bla OXA-58-like was the most common carbapenemase gene in A.baumannii before 2008, thereafter bla OXA-23-like became rapidly prevalent and replaced bla OXA-58-like in 2009. The majority of bla OXA-58-like-carrying isolates showed lower level of resistance to imipenem and meropenem (minimum inhibitory concentrations (MICs), 1 μg/ml to 16 μg/ml), compared with the majority of bla OXA-23-like-carrying isolates (MICs, 16 μg/ml to 64 μg/ml for both imipenem and meropenem). All 231 bla OXA carbapenemase gene-harboring isolates belonged to 14 PFGE types (A–N), and three dominant clones A, J, and H accounted for 43.3%, 42.0%, and 8.2% of the tested isolates, respectively. Clone A (sequence type ST92/ST208) with bla OXA-58-like was the most prevalent before 2008. Clone H (ST229) with bla OXA-23-like became striking between 2007 and 2008. Clone J (ST381) with bla OXA-23-like rapidly spread and replaced clones A and H in 2009.Conclusion
This study is the first to reveal that the distinct bla OXA-23-like-carrying A. baumannii ST381 displaced the previously prevalent bla OXA-58-like-carrying A. baumannii ST92/ST208, resulting in the rapidly increasing resistance to carbapenems in A. baumannii in Shenzhen People’s Hospital in 2009. 相似文献5.
Acinetobacter baumannii has been prevalent in nosocomial infections, often causing outbreaks in intensive care units. ISAba1 is an insertion sequence that has been identified only in A. baumannii and its copy number varies among strains. It has been reported that ISAba1 provides a promoter for blaOXA-51-like, blaOXA-23-like, and blaampC, which are associated with the resistance of A. baumannii to carbapenems and cephalosporins. The main purpose of this study was to develop a novel inverse PCR method capable of typing A. baumannii strains. The method involves three major steps: cutting of genomic DNA with a restriction enzyme, ligation, and PCR. In the first step, bacterial genomic DNA was digested with DpnI. In the second step, the digested genomic DNAs were ligated to form intramolecular circular DNAs. In the last step, the ligated circular DNAs were amplified by PCR with primers specific for ISAba1 and the amplified PCR products were electrophoresed. Twenty-two clinical isolates of A. baumannii were used for the evaluation of the inverse PCR (iPCR) typing method. Dendrogram analysis revealed two major clusters, similar to pulsed-field gel electrophoresis (PFGE) results. Three ISAba1-associated genes — blaampC, blaOXA-66-like, and csuD — were amplified and detected in the clinical isolates. This novel iPCR typing method is comparable to PFGE in its ability to discriminate A. baumannii strains, and is a promising molecular epidemiological tool for investigating A. baumannii carrying ISAba1. 相似文献
6.
The emergence and spread of NDM-1-producing Enterobacteriaceae have resulted in a worldwide public health risk that has affected some provinces of China. China is an exceptionally large country, and there is a crucial need to investigate the epidemic of bla
NDM-1-positive Enterobacteriaceae in our province. A total of 186 carbapenem-resistant Enterobacteriaceae isolates (CRE) were collected in a grade-3 hospital in Zhejiang province. Carbapenem-resistant genes, including bla
KPC, bla
IMP, bla
VIM, bla
OXA-48 and bla
NDM-1 were screened and sequenced. Ninety isolates were identified as harboring the bla
KPC-2 genes, and five bla
NDM-1-positive isolates were uncovered. XbaI-PFGE revealed that three bla
NDM-1-positive K. pneumoniae isolates belonged to two different clones. S1-PFGE and southern blot suggested that the bla
NDM-1 genes were located on IncX3-type plasmids with two different sizes ranging from 33.3 to 54.7 kb (n=4) and 104.5 to 138.9 kb (n=1), respectively, all of which could easily transfer to Escherichia coli by conjugation and electrotransformation. The high-throughput sequencing of two plasmids was performed leading to the identification of a smaller 54-kb plasmid, which had high sequence similarity with a previously reported pCFNDM-CN, and a larger plasmid in which only a 7.8-kb sequence of a common gene environment around bla
NDM-1 (bla
NDM-1-trpF- dsbC-cutA1-groEL-ΔInsE,) was detected. PCR mapping and sequencing demonstrated that four smaller bla
NDM-1 plasmids contained a common gene environment around bla
NDM-1 (IS5-bla
NDM-1-trpF- dsbC-cutA1-groEL). We monitored the CRE epidemic in our hospital and determined that KPC-2 carbapenemase was a major risk to patient health and the IncX3-type plasmid played a vital role in the spread of the bla
NDM-1 gene among the CRE. 相似文献
7.
Sumbal Nosheen Nadeem Irfan Bukhari Kashaf Junaid Naeem Anwar Fahad Ahmad Sonia Younas Hasan Ejaz 《Saudi Journal of Biological Sciences》2021,28(10):5875
The evolution of NDM genes (blaNDM) in E. coli is accounted for expansive multidrug resistance (MDR), causing severe infections and morbidities in the pediatric population. This study aimed to analyze the phylogeny and mutations in NDM variants of E. coli recovered from the pediatric population. Carbapenem-resistant clinical strains of E. coli were identified using microbiological phenotypic techniques. PCR technique used to amplify the blaNDM genes, identified on agarose gel, and analyzed by DNA sequencing. The amino acid substitutions were examined for mutations after aligning with wild types. Mutational and phylogenetic analysis was performed using Lasergene, NCBI blastn, Clustal Omega, and MEGA software, whereas PHYRE2 software was used for the protein structure predictions. PCR amplification of the blaNDM genes detected 113 clinical strains of E. coli with the contribution of blaNDM-1 (46%), blaNDM-4 (3.5%), and blaNDM-5 (50%) variants. DNA sequencing of blaNDM variants showed homology to the previously described blaNDM-1, blaNDM-4, and blaNDM-5 genes available at GenBank and NCBI database. In addition, the mutational analysis revealed in frame substitutions of Pro60Ala and Pro59Ala in blaNDM-4 and blaNDM-5, respectively. The blaNDM-1 was ortholog with related sequences of E. coli available at GenBank. The phylogenetic analysis indicated that the NDM gene variants resemble other microbes reported globally with some new mutational sites. 相似文献
8.
《Saudi Journal of Biological Sciences》2021,28(10):5875-5883
The evolution of NDM genes (blaNDM) in E. coli is accounted for expansive multidrug resistance (MDR), causing severe infections and morbidities in the pediatric population. This study aimed to analyze the phylogeny and mutations in NDM variants of E. coli recovered from the pediatric population. Carbapenem-resistant clinical strains of E. coli were identified using microbiological phenotypic techniques. PCR technique used to amplify the blaNDM genes, identified on agarose gel, and analyzed by DNA sequencing. The amino acid substitutions were examined for mutations after aligning with wild types. Mutational and phylogenetic analysis was performed using Lasergene, NCBI blastn, Clustal Omega, and MEGA software, whereas PHYRE2 software was used for the protein structure predictions. PCR amplification of the blaNDM genes detected 113 clinical strains of E. coli with the contribution of blaNDM-1 (46%), blaNDM-4 (3.5%), and blaNDM-5 (50%) variants. DNA sequencing of blaNDM variants showed homology to the previously described blaNDM-1, blaNDM-4, and blaNDM-5 genes available at GenBank and NCBI database. In addition, the mutational analysis revealed in frame substitutions of Pro60Ala and Pro59Ala in blaNDM-4 and blaNDM-5, respectively. The blaNDM-1 was ortholog with related sequences of E. coli available at GenBank. The phylogenetic analysis indicated that the NDM gene variants resemble other microbes reported globally with some new mutational sites. 相似文献
9.
Background/Objective
Several studies have described the epidemiological distribution of bla OXA-58-harboring Acinetobacter baumannii in China. However, there is limited data concerning the replicon types of bla OXA-58-carrying plasmids and the genetic context surrounding bla OXA-58 in Acinetobacter spp. in China.Methodology/Principal Findings
Twelve non-duplicated bla OXA-58-harboring Acinetobacter spp. isolates were collected from six hospitals in five different cities between 2005 and 2010. The molecular epidemiology of the isolates was carried out using PFGE and multilocus sequence typing. Carbapenemase-encoding genes and plasmid replicase genes were identified by PCR. The genetic location of bla OXA-58 was analyzed using S1-nuclease method. Plasmid conjugation and electrotransformation were performed to evaluate the transferability of bla OXA-58-harboring plasmids. The genetic structure surrounding bla OXA-58 was determined by cloning experiments. The twelve isolates included two Acinetobacter pittii isolates (belong to one pulsotype), three Acinetobacter nosocomialis isolates (belong to two pulsotypes) and seven Acinetobacter baumannii isolates (belong to two pulsotypes/sequence types). A. baumannii ST91 was found to be a potential multidrug resistant risk clone carrying both bla OXA-58 and bla OXA-23. bla OXA-58 located on plasmids varied from ca. 52 kb to ca. 143 kb. All plasmids can be electrotransformed to A. baumannii recipient, but were untypeable by the current replicon typing scheme. A novel plasmid replicase named repAci10 was identified in bla OXA-58-harboring plasmids of two A. pittii isolates, three A. nosocomialis isolates and two A. baumannii isolates. Four kinds of genetic contexts of bla OXA-58 were identified. The transformants of plasmids with structure of IS6 family insertion sequence (ISOur1, IS1008 or IS15)-ΔISAba3-like element-bla OXA-58 displayed carbapenem nonsusceptible, while others with structure of intact ISAba3-like element-bla OXA-58 were carbapenem susceptible.Conclusion
The study revealed the unique features of bla OXA-58-carrying plasmids in Acinetobacter spp. in China, which were different from that of Acinetobacter spp. found in European countries. The diversity of the genetic contexts of bla OXA-58 contributed to various antibiotics resistance profiles. 相似文献10.
Background
The NDM-1 carbapenemase has been identified in 2008 in Enterobacteriaceae. Since then, several reports have emphasized its rapid dissemination throughout the world. The spread of NDM carbapenemases involve several bla NDM gene variants associated with various plasmids among several Gram negative species.Methodology
A multidrug-resistant E. coli isolate recovered from urine of a patient who had travelled to Burma has been characterized genetically and biochemically.Principal Findings
E. coli COU was resistant to all antibiotics tested except amikacin, tigecycline, fosfomycin, and chloramphenicol. Analysis of the antibiotic resistance traits identified a metallo-ß-lactamase, a novel NDM variant, NDM-7. It differs from NDM-4 by a single amino acid substitution sharing an identical extended spectrum profile towards carbapenems. The bla NDM-7 gene was located on an untypeable conjugative plasmid and associated with a close genetic background similar to those described among the bla NDM-1 genes. The isolate also harbours bla CTXM-15 and bla OXA-1 genes and belonged to ST167.Significance
This study highlights that spread of NDM producers correspond to spread of multiple bla NDM genes and clones and therefore will be difficult to control. 相似文献11.
Aims: This study was performed to describe the epidemiological traits of ceftazidime‐resistant Acinetobacter baumannii clinical isolates from Korea. Methods and Results: Antimicrobial susceptibilities were determined by disk diffusion assay. PCR experiments were performed to detect genes encoding extended‐spectrum β‐lactamases and metallo‐β‐lactamases. Detection of ISAba1 upstream of the blaADC gene was also performed by PCR amplification. The genetic organization of the blaPER‐1 gene was investigated by PCR mapping and sequencing of the regions surrounding the gene. Multilocus sequence typing was performed using seven housekeeping genes. A. baumannii isolates of clonal complex (CC) 92 exhibited a higher resistance rate (286/289, 99%) against ceftazidime compared to A. baumannii isolates of non‐CC92 (7/87, 8%). Amongst 286 ceftazidime‐resistant isolates of CC92, 100 (35%) isolates carried the blaPER‐1 gene, while none of the 87 isolates of non‐CC92 carried the gene. The blaADC gene associated with an ISAba1 element was detected in 98% (281/286) of ceftazidime‐resistant isolates of CC92 and in all seven ceftazidime‐resistant isolates of non‐CC92. The blaPER‐1 gene was located on a transposon, Tn1213 (ISPa12‐blaPER‐1‐Δgst‐ISPa13), in 95 isolates and on a complex class 1 integron (orf513‐blaPER‐1‐putative ABC transporter gene) in five isolates. Southern blot experiments confirmed the chromosomal location of the blaPER‐1 gene. Conclusions: Acinetobacter baumannii CC92 which has acquired ceftazidime resistance by the production of PER‐1 extended‐spectrum β‐lactamases and/or the overproduction of Acinetobacter‐derived cephalosporinase is widely disseminated in Korea. Significance and Impact of the Study: This study shows the mechanisms of acquiring ceftazidime resistance in A. baumannii and the epidemiological traits of ceftazidime‐resistant A. baumannii isolates from Korea. 相似文献
12.
Cailin Liu Shangshang Qin Hui Xu Lijuan Xu Di Zhao Xuchun Liu Shaolei Lang Xianju Feng Hong-Min Liu 《PloS one》2015,10(8)
The emergence of New Delhi metallo-β-lactamase 1 (NDM-1) has become established as a major public health threat and represents a new challenge in the treatment of infectious diseases. In this study, we report a high incidence and endemic spread of NDM-1-producing carbapenem-resistant Enterobacter cloacae isolates in Henan province, China. Eight (72.7%) out of eleven non-duplicated carbapenem-resistant E. cloacae isolates collected between June 2011 and May 2013 were identified as NDM-1 positive. The bla
NDM-1 gene surrounded by an entire ISAba125 element and a bleomycin resistance gene ble
MBL in these isolates were carried by diverse conjugatable plasmids (IncA/C, IncN, IncHI2 and untypeable) ranging from ~55 to ~360 kb. Molecular epidemiology analysis revealed that three NDM-1-producing E. cloacae belonged to the same multilocus sequence type (ST), ST120, two of which were classified as extensively drug-resistant (XDR) isolates susceptible only to tigecycline and colistin. The two XDR ST120 E. cloacae isolates co-harbored bla
NDM-1, armA and fosA3 genes and could transfer resistance to carbapenems, fosfomycin and aminoglycosides simultaneously via a conjugation experiment. Our study demonstrated NDM-1 was the most prevalent metallo-β-lactamase (MBL) among carbapenem-resistant E.cloacae isolates and identified a potential endemic clone of ST120 in Henan province. These findings highlight the need for enhanced efforts to monitor the further spread of NDM-1 and XDR ST120 E. cloacae in this region. 相似文献
13.
Brandusa Elena Lixandru Ani Ioana Cotar Monica Straut Codruta Romanita Usein Dana Cristea Simona Ciontea Dorina Tatu-Chitoiu Irina Codita Alexandru Rafila Maria Nica Mariana Buzea Anda Baicus Mihaela Camelia Ghita Irina Nistor Cristina Tuchilu? Marina Indreas Felicia Antohe Corinna Glasner Hajo Grundmann Aftab Jasir Maria Damian 《PloS one》2015,10(11)
14.
Tzu-Wen Huang Te-Li Chen Ying-Tsong Chen Tsai-Ling Lauderdale Tsai-Lien Liao Yi-Tzu Lee Chien-Pei Chen Yen-Ming Liu Ann-Chi Lin Ya-Hui Chang Keh-Ming Wu Ralph Kirby Jui-Fen Lai Mei-Chen Tan Leung-Kei Siu Chung-Ming Chang Chang-Phone Fung Shih-Feng Tsai 《PloS one》2013,8(4)
The genetic features of the antimicrobial resistance of a multidrug resistant Klebsiella pneumoniae strain harboring bla
NDM-1 were investigated to increase our understanding of the evolution of NDM-1. The strain, KPX, came from a Taiwanese patient with a hospitalization history in New Delhi. Complete DNA sequencing was performed; and the genes responsible for antimicrobial resistance were systematically examined and isolated by library screening. KPX harbored two resistance plasmids, pKPX-1 and pKPX-2, which are 250-kb and 141-kb in size, respectively, with bla
NDM-1 present on pKPX-1. The plasmid pKPX-1 contained genes associated with the IncR and IncF groups, while pKPX-2 belonged to the IncF family. Each plasmid carried multiple antimicrobial resistance genetic determinants. The gene responsible for resistance to carbapenems was found on pKPX-1 and that for resistance to aztreonam was found on pKPX-2. To our surprise, we discovered that bla
NDM-1 exists on pKPX-1 as multiple copies in the form of tandem repeats. Amplification of bla
NDM-1 was found to occur by duplication of an 8.6-kb unit, with the copy number of the repeat varying from colony to colony. This repeat sequence is identical to that of the pNDM-MAR except for two base substitutions. The copy number of bla
NDM-1 of colonies under different conditions was assessed by Southern blotting and quantitative PCR. The bla
NDM-1 sequence was maintained in the presence of the antimicrobial selection; however, removal of antimicrobial selection led to the emergence of susceptible bacterial populations with a reduced copy number or even the complete loss of the bla
NDM-1 sequence. The dynamic nature of the NDM-1 sequence provides a strong argument for judicious use of the broad-spectrum antimicrobials in order to reduce the development and spread of antimicrobial resistance among pathogens. 相似文献
15.
Objectives
The study aimed to investigate the prevalence and epidemiological characteristics of bla NDM-1 (encoding New Delhi metallo-β-lactamase 1) in Enterobacteriaceae and the Acinetobacter calcoaceticus-Acinetobacter baumannii complex (ABC) in China from July 2011 to June 2012.Methods
PCR was used to screen for the presence of bla NDM-1 in all organisms studied. For bla NDM-1-positive strains, 16S rRNA analysis and Analytical Profile Index (API) strips were used to identify the bacterial genus and species. The ABCs were reconfirmed by PCR detection of bla OXA-51-like. Antibiotic susceptibilities of the bacteria were assessed by determining minimum inhibitory concentration (MIC) of them using two-fold agar dilution test, as recommended by the Clinical and Laboratory Standards Institute (CLSI). Molecular typing was performed using pulsed-field gel electrophoresis (PFGE). S1 nuclease-pulsed-field gel electrophoresis (S1-PFGE) and Southern blot hybridization were conducted to ascertain the gene location of bla NDM-1. Conjugation experiments were conducted to determine the transmission of bla NDM-1-positive strains.Results
Among 2,170 Enterobacteriaceae and 600 ABCs, seven Enterobacteriaceae strains and two A. calcoaceticus isolates from five different cities carried the bla NDM-1 gene. The seven Enterobacteriaceae strains comprised four Klebsiella pneumoniae, one Enterobacter cloacae, one Enterobacter aerogen and one Citrobacter freundii. All seven were non-susceptible to imipenem, meropenem or ertapenem. Two A. calcoaceticus species were resistant to imipenem and meropenem. Three K. pneumoniae showed the same PFGE profiles. The bla NDM-1 genes of eight strains were localized on plasmids, while one was chromosomal.Conclusions
Compared with previous reports, the numbers and species containing the bla NDM-1 in Enterobacteriaceae have significantly increased in China. Most of them are able to disseminate the gene, which is cause for concern. Consecutive surveillance should be implemented and should also focus on the dissemination of bla NDM-1 among gram-negative clinical isolates. 相似文献16.
Supriya Upadhyay Abbas Hussain Shweta Mishra Anand Prakash Maurya Amitabha Bhattacharjee Santa Ram Joshi 《PloS one》2015,10(9)
Background
The study investigated the presence of CTX-M-15 type extended spectrum beta-lactamases (ESBL), compared their genetic arrangements and plasmid types in gram negative isolates of hospital and food origin in north-east India. From September 2013 to April 2014, a total of 252 consecutive, non-duplicate clinical isolates and 88 gram negative food isolates were selected. Phenotypic and molecular characterization of ESBL genes was performed. Presence of integrons and gene cassettes were analyzed by integrase and 59 base-element PCR respectively. The molecular environments surrounding bla CTX-M and plasmid types were investigated by PCR and PCR-based replicon typing respectively. Transformation was carried out to assess plasmid transfer. Southern blotting was conducted to localize the bla CTX-M-15 genes. DNA fingerprinting was performed by ERIC-PCR.Results
Prevalence of ESBL was found to be 40.8% (103/252) in clinical and 31.8% (28/88) in food-borne isolates. Molecular characterization revealed the presence of 56.3% (58/103) and 53.5% (15/28) bla CTX-M-15 in clinical and food isolates respectively. Strains of clinical and food origin were non-clonal. Replicon typing revealed that IncI1 and IncFII plasmid were carrying bla CTX-M-15 in clinical and food isolates and were horizontally transferable. The ISEcp1 element was associated with bla CTX-M-15 in both clinical and food isolates.Conclusions
The simultaneous presence of resistance determinants in non-clonal isolates of two different groups thus suggests that the microbiota of common food products consumed may serve as a reservoir for some of the drug resistance genes prevalent in human pathogens. 相似文献17.
G. Ripabelli M.L. Sammarco A. Salzo M. Scutellà V. Felice M. Tamburro 《Letters in applied microbiology》2020,71(6):652-659
The emergence of novel resistant markers hampers the efficacy of beta-lactam antibiotics to treat infections caused by micro-organisms carrying such resistances. This study investigated the antimicrobial susceptibility pattern, the carpapenem-associated determinants and the molecular epidemiology of Klebsiella pneumoniae showing a New Delhi (NDM) metallo-β-lactamase phenotype, isolated from a patient admitted to intensive care unit of the main hospital for acute care of Molise region, central Italy. Antimicrobial susceptibility was assessed for nineteen antibiotics by disc diffusion and agar dilution methods. Carbapenem-associated resistance determinants were detected through gene-specific amplifications, targeting blaNDM-1, blaSHV and blaTEM, blaCTX-M, blaKPC, blaVIM, blaIMP, blaGES and blaOXA-48-lixe. Molecular characterization was carried out through multilocus sequence typing. The strain showed a multidrug resistant profile, and PCR and sequencing confirmed the presence of blaNDM-1 gene. Among the multiple resistance-associated determinants tested, the isolate, which was assigned to the sequence type ST11, only harboured blaSHV and blaTEM genes. This is the first report of NDM-1 variant in the regional healthcare setting for acute patients, raising significant concerns about the increase in the antimicrobials resistance spread through a different mechanism from the endemic KPC carbapenemase, and underlining the circulation of a virulent clone never identified before in this area. 相似文献
18.
DOROTA OCHOSKA HANNA KLAMISKA-CEBULA ANNA DOBRUT MAGORZATA BULANDA MONIKA BRZYCHCZY-WOCH 《Polish journal of microbiology》2021,70(1):107
Carbapenem-resistant Klebsiella pneumoniae (CRKP) is an important bacterium of nosocomial infections. In this study, CRKP strains, which were mainly isolated from fecal samples of 14 patients in three wards of the hospital in the Silesia Voivodship, rapidly increased from February to August 2018. Therefore, we conducted microbiological and molecular studies of the CRKP isolates analyzed. Colonized patients had critical underlying diseases and comorbidities; one developed bloodstream infection, and five died (33.3%). Antibiotic susceptibilities were determined by the E-test method. A disc synergy test confirmed carbapenemase production. CTX-Mplex PCR evaluated the presence of resistance genes blaCTX-M-type, blaCTX-M-1, blaCTX-M-9, and the genes blaSHV, blaTEM, blaKPC-2, blaNDM-1, blaOXA-48, blaIMP, and blaVIM-1 was detected with the PCR method. Clonality was evaluated by Multi Locus Sequence Typing (MLST) and Pulsed Field Gel Electrophoresis (PFGE). Six (40%) strains were of XDR (Extensively Drug-Resistant) phenotype, and nine (60%) of the isolates exhibited MDR (Multidrug-Resistant) phenotype. The range of carbapenem minimal inhibitory concentrations (MICs, μg/mL) was as follows doripenem (16 to >32), ertapenem (> 32), imipenem (4 to > 32), and meropenem (> 32). PCR and sequencing confirmed the blaCTX-M-15, blaKPC-2, blaOXA-48, and blaVIM-1 genes in all strains. The isolates formed one large PFGE cluster (clone A). MLST assigned them to the emerging high-risk clone of ST147 (CC147) pandemic lineage harboring the blaOXA-48 gene. This study showed that the K. pneumoniae isolates detected in the multi-profile medical centre in Katowice represented a single strain of the microorganism spreading in the hospital environment. 相似文献
19.
ágnes Sonnevend Akela A. Ghazawi Rayhan Hashmey Wafaa Jamal Vincent O. Rotimi Atef M. Shibl Amina Al-Jardani Seif S. Al-Abri Waheed U. Z. Tariq Stefan Weber Tibor Pál 《PloS one》2015,10(6)
To establish the role of local transmission versus possible pathogen import due to previous foreign exposure in infections caused by carbapenem non-susceptible Enterobacteriaceae in the Arabian Peninsula, 200 independent isolates collected in 16 hospitals of Saudi Arabia, Kuwait, Oman and the United Arab Emirates were studied. All strains were multidrug resistant; 42.5% of them also qualified as extremely drug resistant. The frequency of various carbapenemases varied according to the participating countries, but in the collection, as a whole, bla
NDM-1 was the most frequently encountered carbapenemase gene (46.5%) followed by bla
OXA-48-like gene (32.5%). A comparatively high rate (8.9%) of multi-clonal strains carrying both bla
NDM and bla
OXA-48-like genes in the United Arab Emirates, representing the most resistant subgroup, was encountered. No KPC-expressing isolates were detected. Three major clones of bla
NDM-1 carrying Klebsiella pneumoniae of ST152 (n = 22, Saudi Arabia), ST14 (n = 7, United Arab Emirates) and ST147 types (n = 9, Oman) were identified, the latter two clones carrying similar, but not identical HI1b incompatibility type plasmids of >170kb. While from 78.6% of the cases with documented foreign hospitalization bla
NDM positive strains were isolated, these strains formed only 25.6% of all the isolates expressing this enzyme. In fact, 56.8% of the NDM, 75.7% of OXA-48-like and 90.9% of VIM positive strains were recovered from patients without documented foreign exposure, neither in the form of travel or prior hospitalization abroad, suggesting a high rate of autochthonous infections. This, considering the extensive links of these countries to the rest of the world, predicts that trends in the local epidemiology of carbapenem resistant strains may increasingly affect the spread of these pathogens on the global scale. These results call for improved surveillance of carbapenem resistant Enterobacteriaceae in the countries of the Arabian Peninsula. 相似文献
20.
Zhiyuan Liu Wei Li Jie Wang Jian Pan Shipeng Sun Yanhua Yu Bing Zhao Yuzhi Ma Tingju Zhang Jie Qi Guijian Liu Fengmin Lu 《PloS one》2013,8(6)
New Delhi metallo-β-lactamase-1 (NDM-1), an acquired class B carbapenemase, is a significant clinical threat due to its extended hydrolysis of β-lactams including carbapenems. In this study, we identified the first confirmed clinical isolate of Escherichia coli BJ01 harboring bla
NDM-1 in China. The isolate is highly resistant to all tested antimicrobials except polymyxin. bla
NDM-1, bla
CTX-M-57, and bla
TEM-1 were identified in the isolate. bla
NDM-1 was transferable to E. coli EC600 and DH5α in both plasmid conjugation experiments and plasmid transformation tests. BJ01 was identified as a new sequence type, ST224, by multilocus sequence typing. Analysis of genetic environment shows complex transposon-like structures surrounding the bla
NDM-1 gene. Genetic analysis revealed that the region flanking bla
NDM-1 was very similar to previously identified NDM-positive Acinetobacter spp. isolated in China. The findings of this study raise attention to the emergence and spread of NDM-1-carrying Enterobacteriaceae in China. 相似文献