scholarly journals Molecular characterization of NDM-1-producing Pseudomonas aeruginosa isolates from hospitalized patients in Iran

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Mojtaba Shahin ◽  
Ali Ahmadi
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antibiotic Resistance Genes ◽  
Healthcare Setting ◽  
Main Cluster ◽  
Carbapenem Resistant ◽  
Pcr Method ◽  
Synergy Test ◽  
Relationship Of ◽  
Encoding Genes

Abstract Background The emergence of carbapenem-resistant Pseudomonas aeruginosa is one of the most important challenges in a healthcare setting. The aim of this study is double-locus sequence typing (DLST) typing of blaNDM-1 positive P. aeruginosa isolates. Methods Twenty-nine blaNDM-1 positive isolates were collected during three years of study from different cities in Iran. Modified hodge test (MHT), double-disk synergy test (DDST) and double-disk potentiation test (DDPT) was performed for detection of carbapenemase and metallo-beta-lactamase (MBL) producing blaNDM-1 positive P. aeruginosa isolates. The antibiotic resistance genes were considered by PCR method. Clonal relationship of blaNDM-1 positive was also characterized using DLST method. Results Antibiotic susceptibility pattern showed that all isolates were resistant to imipenem and ertapenem. DDST and DDPT revealed that 15/29 (51.8%) and 26 (89.7%) of blaNDM-1 positive isolates were MBL producing isolates, respectively. The presence of blaOXA-10,blaVIM-2, blaIMP-1 and blaSPM genes were detected in 86.2%, 41.4%, 34.5% and 3.5% isolates, respectively. DLST typing results revealed the main cluster were DLST 25-11 with 13 infected or colonized patients. Conclusions The presence of blaNDM-1 gene with other MBLs encoding genes in P. aeruginosa is a potential challenge in the treatment of microorganism infections. DLST showed partial diversity among 29 blaNDM-1 positive isolates.

scholarly journals Molecular characterization of clinical carbapenem-resistant Enterobacterales from Qatar

2021 ◽  
Author(s):  
Fatma Ben Abid ◽  
Clement K. M. Tsui ◽  
Yohei Doi ◽  
Anand Deshmukh ◽  
Christi L. McElheny ◽  
...  
Keyword(s):  
Common Species ◽  
Clinical Samples ◽  
Whole Genome ◽  
E Coli ◽  
Carbapenem Resistant ◽  
Genes Encoding ◽  
Encoding Genes ◽  
Sequence Types ◽  
Common Sequence

AbstractOne hundred forty-nine carbapenem-resistant Enterobacterales from clinical samples obtained between April 2014 and November 2017 were subjected to whole genome sequencing and multi-locus sequence typing. Klebsiella pneumoniae (81, 54.4%) and Escherichia coli (38, 25.5%) were the most common species. Genes encoding metallo-β-lactamases were detected in 68 (45.8%) isolates, and OXA-48-like enzymes in 60 (40.3%). blaNDM-1 (45; 30.2%) and blaOXA-48 (29; 19.5%) were the most frequent. KPC-encoding genes were identified in 5 (3.6%) isolates. Most common sequence types were E. coli ST410 (8; 21.1%) and ST38 (7; 18.4%), and K. pneumoniae ST147 (13; 16%) and ST231 (7; 8.6%).

scholarly journals Investigation of Metallo-Beta-Lactamases in Carbapenem Resistant Pseudomonas aeruginosa Strains by Phenotypic and Genotypic Methods

2020 ◽  
Vol 25 (3) ◽  
pp. 301-307
Author(s):  
M. Duygu Aksoy ◽  
H. Murat Tuğrul
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Ethylenediaminetetraacetic Acid ◽  
Carbapenem Resistance ◽  
Beta Lactamase ◽  
Bacterial Strains ◽  
Beta Lactamases ◽  
Carbapenem Resistant ◽  
Synergy Test ◽  
Phenotypic Tests ◽  
Positive Controls

Introduction: Carbapenem resistant Pseudomonas aeruginosa strains cause serious problems in treatment. A large number of identified metallo-beta-lactamase (MBL) enzymes produced by P. aeruginosa are one of the most important mechanisms in resistance to carbapenems. MBL genes are located on the chromosome or plasmid, and they can easily spread between different bacterial strains. The activities of these enzymes are zinc-dependent, and they are inhibited by ethylenediaminetetraacetic acid (EDTA). Therefore, this advantage is used in MBL identification tests. In this study, it was aimed to determine MBL among P. aeruginosa strains. Materials and Methods: MBL existence was investigated in 35 P. aeruginosa strains accepted to be mildly susceptible/resistant to any of the carbapenem group of antibiotics through phenotypic and genotypic methods. Phenotypic tests were performed as double disk synergy test (DDST), combined disk diffusion tests (CDDT) by using 0.1 M and 0.5 M EDTA, MBL E-test, and modified Hodge test (MHT). blaIMP, blaVIM, blaGIM, blaSIM, blaSPM genes and blaNDM gene were investigated by multiplex polimerase chain reaction (PCR) and PCR, respectively. Escherichia coli ATCC 25922 and P. aeruginosa ATCC 27853 standard bacteria were used in tests. VIM-1, VIM-2, IMP-13, SPM-1, NDM-1 type MBL-producing P. aeruginosa strains were used as positive controls. Results: Among the carbapenems resistant P. aeruginosa isolates, positivity of MBL was found as 54.2% by MBL E-test, 42.8% by DDST, 94.2% and 37.1% by CDDT method using 0.5 M and 0.1 M EDTA, respectively. Modified Hodge test and genotypic method did not detect MBL. Conclusion: In order to correctly evaluate the results of the phenotypic method, the investigation of resistance genes by molecular methods is also required. The most common metallo-beta-lactamase enzymes responsible for resistance to carbapenem in Pseudomonas were not observed. It was thought that different mechanisms might be responsible for the identified carbapenem resistance.

scholarly journals Isolation and characterization of a sequence type 25 carbapenem-resistant hypervirulent Klebsiella pneumoniae from the mid-south region of China

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Jun Li ◽  
Zi-Yan Huang ◽  
Ting Yu ◽  
Xiao-Yan Tao ◽  
Yong-Mei Hu ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Capsular Polysaccharide ◽  
Control Strategies ◽  
Virulence Gene ◽  
Sequence Type ◽  
Pfge Typing ◽  
Main Cluster ◽  
Carbapenem Resistant ◽  
Isolation And Characterization

Abstract Background The molecular characterization of carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKP) isolates is not well studied. Our goal was to investigate the molecular epidemiology of CR-hvKP strains that were isolated from a Chinese hospital. Results All clinical carbapenem-resistant K. pneumoniae (CR-KP) isolates were collected and identified from patient samples between 2014 and 2017 from a Chinese hospital. The samples were subjected to screening for CR-hvKP by string test and the detection of the aerobactin gene. CR-hvKP isolates were further confirmed through neutrophil phagocytosis and a mice lethality assay. The CR-hvKP isolates were investigated for their capsular genotyping, virulence gene profiles, and the expression of carbapenemase genes by PCR and DNA sequencing. Multilocus sequence type (MLST) and pulsed-field gel electrophoresis (PFGE) were performed to exclude the homology of these isolates. Twenty strains were identified as CR-hvKP. These strains were resistant to imipenem and several other antibiotics, however, most were susceptible to amikacin. Notably, two isolates were not susceptible to tigecycline. Capsular polysaccharide synthesis genotyping revealed that 17 of the 20 CR-hvKP strains belonged to the K2 serotype, while the others belonged to serotypes other than K1, K2, K5, K20, and K57. The strains were found to be positive for 10 types of virulence genes and a variety of these genes coexisted in the same strain. Two carbapenemase genes were identified: blaKPC-2 (13/20) and blaNDM-1 (1/20). PFGE typing revealed eight clusters comprising isolates that belonged to MLST types ST25, ST11 and ST375, respectively. PFGE cluster A was identified as the main cluster, which included 11 isolates that belong to ST25 and mainly from ICU department. Conclusions Our findings suggest that hospital-acquired infections may contribute in part to the CR-hvKP strains identified in this study. It also suggests that ST25 CR-hvKP strain has a clonal distribution in our hospital. Therefore, effective surveillance and strict infection control strategies should be implemented to prevent outbreak by CR-hvKP strains in hospitals setting.

scholarly journals Comprehensive Genome Analysis of Carbapenem-Resistant Strains of Raoultella Species, an Emerging Multidrug-Resistant Bacterium in Hospitals

2019 ◽  
Vol 63 (12) ◽  
Author(s):  
Xiao Yu ◽  
Beiwen Zheng ◽  
Jing Zhang ◽  
Hao Xu ◽  
Tingting Xiao ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Antibiotic Resistance Genes ◽  
Genomic Analysis ◽  
Multidrug Resistant ◽  
Control Measures ◽  
Carbapenem Resistant ◽  
Multidrug Resistant Bacterium ◽  
The World ◽  
Resistant Strains

ABSTRACT We report the characterization of six carbapenem-resistant Raoultella spp. (CRRS) in our hospital and a genomic analysis of 58 publicly available isolates. CRRS isolates are sporadically identified around the world, and different transposons carrying carbapenemases were the resistant mechanisms. Mobile genetic elements play an important role in acquiring antibiotic resistance genes from the hospital. An improved understanding of these transposon and targeted control measures will be very valuable to prevent CRRS dissemination.

scholarly journals Characterization of N4-like Pseudomonas Phage vB_Pae-PA14 Isolated from Seawater Sampled in Thailand

2021 ◽  
Author(s):  
Akkaraphol Srichaisupakit ◽  
Peechanika Chopjitt ◽  
Anusak Kerdsin
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Phylogenetic Analysis ◽  
Burst Size ◽  
Biological Entity ◽  
Whole Genome ◽  
Lytic Bacteriophage ◽  
Carbapenem Resistant ◽  
Infected Cells ◽  
Range Test

Bacteriophage, a predator virus of bacteria, is an abundant biological entity in the biosphere. With ultimate applications in medicine and biotechnology, new phages are extensively being isolated and characterized. The objective of the present study was to characterize lytic bacteriophage vB_Pae-PA14 infecting Pseudomonas aeruginosa ATCC 27853 that was isolated from seawater in Thailand. vB_Pae-PA14 was subjected to whole genome phylogenetic analysis, host range test, biofilm test and characterization. Results showed that the phage belonged to a group of N4-like viruses, could infect P. aeruginosa isolates including carbapenem-resistant P. aeruginosa. The burst size of vB_Pae-PA14 was 86 plaque-forming unit/infected cells. Also, the phage showed a greater ability to control planktonic P. aeruginosa cells than the biofilm cells. Phage could withstand physical stresses especially the high salt concentration. In brief, lytic bacteriophage vB_Pae-PA14 infecting P. aeruginosa was isolated and characterized, which might be useful in further bacteriophage lytic applications.

scholarly journals Genomic Characterization of a Proteus sp. Strain of Animal Origin Co-Carrying blaNDM-1 and lnu(G)

Antibiotics ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1411
Author(s):  
Ying Li ◽  
Yichuan Qiu ◽  
Junping She ◽  
Xu Wang ◽  
Xiaoyi Dai ◽  
...  
Keyword(s):  
Resistance Genes ◽  
Treatment Options ◽  
Antibiotic Resistance Genes ◽  
Animal Origin ◽  
Global Public Health ◽  
Carbapenem Resistant ◽  
Extensive Drug Resistance ◽  
Genetic Features ◽  
Genomic Characterization

The emergence of carbapenem-resistant Proteus represents a serious threat to global public health due to limited antibiotic treatment options. Here, we characterize a Proteus isolate NMG38-2 of swine origin that exhibits extensive drug resistance, including carbapenems. Whole-genome sequencing based on Illumina and MinION platforms showed that NMG38-2 contains 24 acquired antibiotic resistance genes and three plasmids, among which, pNDM_NMG38-2, a pPvSC3-like plasmid, is transferable and co-carries blaNDM-1 and lnu(G). Sequence analysis of pPvSC3-like plasmids showed that they share a conserved backbone but have a diverse accessory module with complex chimera structures bearing abundant resistance genes, which are facilitated by transposons and/or homologous recombination. The acquisition of blaNDM-1 in pNDM_NMG38-2 was due to the ISCR1-mediated integration event. Comprehensive analysis of the lnu(G)-bearing cassettes carried by bacterial plasmids or chromosomes revealed a diversification of its genetic contexts, with Tn6260 and ISPst2 elements being the leading contributors to the dissemination of lnu(G) in Enterococcus and Enterobacteriaceae, respectively. In conclusion, this study provides a better understanding of the genetic features of pPvSC3-like plasmids, which represent a novel plasmid group as a vehicle mediating the dissemination of blaNDM-1 among bacteria species. Moreover, our results highlight the central roles of Tn6260 and ISPst2 in the spread of lnu(G).

scholarly journals Isolation and characterization of a lytic bacteriophage against Pseudomonas aeruginosa

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sonika Sharma ◽  
Sibnarayan Datta ◽  
Soumya Chatterjee ◽  
Moumita Dutta ◽  
Jhuma Samanta ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Burst Size ◽  
Antibiotic Resistance Genes ◽  
Multidrug Resistant ◽  
Potential Candidate ◽  
Lytic Bacteriophage ◽  
Isolation And Characterization ◽  
Phage Proteins

AbstractIn recent years, the use of bacteriophages (or 'phages') against multidrug-resistant (MDR) bacteria including Pseudomonas aeruginosa has drawn considerable attention, globally. In this work, we report the isolation and detailed characterization of a highly lytic Pseudomonasphage DRL-P1 isolated from wastewater. Under TEM, DRL-P1 appeared as a member of the phage family Myoviridae. DRL-P1 featured rapid adsorption (~ 5 min), short-latency (~ 30 min), and large burst size (~ 100 PFU per infected cell). DRL-P1 can withstand a wide temperature range (4 °C to 40 °C) and pH (5.0 to 10.0) conditions. The 66,243 bp DRL-P1 genome (MN564818) encodes at least 93 ORFs, of which 36 were functionally annotated based on homology with similar phage proteins available in the databases. Comparative analyses of related genomes suggest an independent evolutionary history and discrete taxonomic position of DRL-P1 within genus Pbunavirus. No toxin or antibiotic resistance genes was identified. DRL-P1 is tolerant to lyophilization and encapsulation techniques and retained lytic activity even after 18 months of storage. We also demonstrated decontaminating potentials of DRL-P1 in vitro, on an artificially contaminated cover-slip model. To the best of our knowledge, this is the first Pbunavirus to be reported from India. Our study suggests DRL-P1 as a potential candidate for various applications.

scholarly journals Plasmid-Mediated Quinolone Resistance in Pseudomonas aeruginosa Isolated from Burn Patients in Tehran, Iran

2020 ◽  
Vol 20 (1) ◽  
pp. 49-55
Author(s):  
Azam Molapour ◽  
Amir Peymani ◽  
Parvaneh Saffarain ◽  
Narges Habibollah-Pourzereshki ◽  
Pooya Rashvand
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antibiotic Susceptibility ◽  
Cross Sectional Study ◽  
Quinolone Resistance ◽  
Burn Patients ◽  
Burn Wound ◽  
Cross Sectional ◽  
Pcr Method ◽  
Clonal Spread ◽  
Relationship Of

Introduction: Plasmid-induced quinolone resistance has raised a great concern in the treatment of serious infections worldwide. The aims of this study were to determine the antibiotic susceptibility, the frequency of qepA, aac(6')-Ib and qnr genes by PCR and sequencing, and typing of the resistant isolates using repetitive extragenic palindromic sequence-based PCR (REPPCR) in Pseudomonas aeruginosa isolated from burn wound infections. Methods: In the current cross-sectional study, 149 P. aeruginosa were isolated from the burn wound samples of patients admitted to Motahari hospital in Tehran, Iran, from February to December 2016. The bacterial isolates were identified using standard laboratory methods and their antibiotic susceptibility to quinolones was evaluated using the standard Kirby-Bauer method, according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. The presence of aac(6')-Ib, qepA, qnrA, qnrB4, qnrB and qnrS genes was assessed using PCR and sequencing methods and clonal relationship of the resistant isolates was evaluated using REP-PCR method. Results: All (100%) isolates showed complete resistance to used quinolone compounds in this study. The qnr and qepA genes were not found, but all (100%) isolates were positive for the presence of aac(6')-Ib gene and the sequencing revealed that all (100%) belong to the aac(6')-Ib-cr variant. REP-PCR showed that the studied isolates belonged to three distinct clones of A (77.9%), B (18.1%), and C (4%). Conclusion: The findings of the present study indicated the presence of aac(6')-Ib-cr variant and lack of the contribution of qnr and qepA in the emergence of resistance to quinolones in P. aeruginosa isolated from burn patients. Considering the importance of clonal spread of these resistant isolates and their significant role in the development of clinical infections, especially in patients with burns, more attention should be paid to the prevention of the dissemination of these resistant isolates.

scholarly journals Prevalence and Characteristics of Metallo-beta Lactamase-positive and High-risk Clone ST235 Pseudomonas aeruginosa at Ardabil Hospitals

2021 ◽  
Vol 14 (3) ◽  
Author(s):  
Somayeh Safarirad ◽  
Mohsen Arzanlou ◽  
Jafar Mohammadshahi ◽  
Hamid Vaez ◽  
Amirhossin Sahebkar ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Continuous Monitoring ◽  
Multidrug Resistant ◽  
Resistance Rate ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
Carbapenem Resistant ◽  
Clonal Relatedness ◽  
Synergy Test ◽  
Highly Virulent

Background: Carbapenems are the most commonly administered drugs for the treatment of multidrug-resistant Pseudomonas aeruginosa (MDR-P. aeruginosa) infections. However, carbapenem-resistant P. aeruginosa is spreading rapidly and has led to a new threat to human health worldwide. Objectives: The current study aimed to determine the prevalence of imipenem-resistant P. aeruginosa, detect metallo-β-lactamase (MBL)-producer isolates, and evaluate their clonal relationships in strains isolated from patients referring to the hospitals of Ardabil city, Iran. Methods: The resistance rate to imipenem was evaluated using the disk diffusion method. Double-disk synergy test and PCR technique were used for phenotypic and genotypic screening of MBL-positive P. aeruginosa, respectively. Ultimately, ERIC-PCR and MLST methods were used for assessing clonal relatedness among the isolates. Results: The prevalence of imipenem-resistant P. aeruginosa strains was estimated at 57.1% (48 out of 84 isolates). In addition, 45 (93.7%) out of 48 imipenem-resistant P. aeruginosa isolates were phenotypically screened as MBL-positive, among which 16 (35.5%) and three (6.6%) isolates harbored blaIMP and blaVIM-1 genes, respectively. However, blaNDM, blaSIM-2, blaSPM, and blaGIM-1 genes were not detected in this study. MBL-producing P. aeruginosa strains were divided into 42 ERIC-PCR types. Based on the results of MLST, P. aeruginosa ST235 was the only identified sequence type. Conclusions: Our results revealed a high and alarming prevalence of imipenem-resistant and blaIMP-positive P. aeruginosa ST235 at Ardabil hospitals. Continuous monitoring is essential to control the further spread of this highly virulent and drug-resistant clone.

scholarly journals Identification of a Chromosomal Integrated DNA Fragment Containing the rmpA2 and iucABCDiutA Virulence Genes in Klebsiella pneumoniae

mSphere ◽  
2020 ◽  
Vol 5 (6) ◽  
pp. e01179-20
Author(s):  
Xuemei Yang ◽  
Lianwei Ye ◽  
Yi Li ◽  
Edward Wai-Chi Chan ◽  
Rong Zhang ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Virulence Genes ◽  
Antibiotic Resistance Genes ◽  
Content Type ◽  
Carbapenem Resistant ◽  
Transmission Mechanisms ◽  
Genetic Features ◽  
Severe Infections ◽  
First Time ◽  
Encoding Genes

ABSTRACTKlebsiella pneumoniae is increasingly being regarded as a reservoir of diverse antibiotic resistance genes and a pathogen that causes severe infections in both the hospital and the community. In this study, we performed molecular characterization of a carbapenem-resistant and highly virulent K. pneumoniae strain recovered from a hospital patient. The virulence-encoding genes rmpA2 and iucABCDiutA were found to be located in the chromosome and are flanked by IS26 elements. These chromosomally located virulence genes, if not incurring fitness costs, are expected to be much more stable than plasmid-located genes. Detailed analysis of the fragment in which these virulence genes are located showed that the fragment can readily form a circular intermediate that may promote integration of this virulence-encoding fragment into various plasmid backbones and other chromosomal regions. Findings in this work provide new insights into mechanisms of transmission of virulence-encoding genes in K. pneumoniae.IMPORTANCE This study reported for the first time and characterized in detail the genetic features of a mobile virulence-encoding fragment located in the chromosome of a clinical virulent K. pneumoniae strain and revealed the occurrence of a transposition event mediated by IS26. This genetic structure could mediate the transposition of the virulence-encoding fragment into various plasmid backbones and chromosomes through formation of a circular intermediate. Therefore, findings in this work provide important insights into the transmission mechanisms of mobile virulence profiles in K. pneumoniae strains and lay the foundation for devising effective intervention approaches aimed at preventing the dissemination of these virulence-encoding elements.

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