scholarly journals NDM-12, a Novel New Delhi Metallo-β-Lactamase Variant from a Carbapenem-Resistant Escherichia coli Clinical Isolate in Nepal

2014 ◽  
Vol 58 (10) ◽  
pp. 6302-6305 ◽  
Author(s):  
Tatsuya Tada ◽  
Basudha Shrestha ◽  
Tohru Miyoshi-Akiyama ◽  
Kayo Shimada ◽  
Hiroshi Ohara ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Clinical Isolate ◽  
Urine Sample ◽  
Enzymatic Activities ◽  
Amino Acid Substitutions ◽  
New Delhi ◽  
Content Type ◽  
Carbapenem Resistant

ABSTRACTA novel New Delhi metallo-β-lactamase variant, NDM-12, was identified in a carbapenem-resistantEscherichia coliclinical isolate obtained from a urine sample from a patient in Nepal. NDM-12 differed from NDM-1 by two amino acid substitutions (M154L and G222D). The enzymatic activities of NDM-12 against β-lactams were similar to those of NDM-1, although NDM-12 showed lowerkcat/Kmratios for all β-lactams tested except doripenem. TheblaNDM-12gene was located in a plasmid of 160 kb.

scholarly journals New Variant of mcr-3 in an Extensively Drug-Resistant Escherichia coli Clinical Isolate Carrying mcr-1 and blaNDM-5

2017 ◽  
Vol 61 (12) ◽  
Author(s):  
Lu Liu ◽  
Yu Feng ◽  
Xiaoxia Zhang ◽  
Alan McNally ◽  
Zhiyong Zong
Keyword(s):  
Escherichia Coli ◽  
Clinical Isolate ◽  
Amino Acid Substitutions ◽  
Drug Resistant ◽  
Content Type ◽  
Carbapenem Resistant ◽  
Resistant Genes ◽  
Extensively Drug Resistant ◽  
New Variant ◽  
Carbapenemase Gene

ABSTRACT A colistin- and carbapenem-resistant Escherichia coli clinical isolate was found to carry two plasmid-borne colistin-resistant genes, mcr-1 and the newly identified mcr-3, and a carbapenemase gene, bla NDM-5. mcr-3 is a new variant (mcr-3.5) in the isolate and encodes three amino acid substitutions compared with the original MCR-3. mcr-3 was carried by a TnAs3-like transposon on a self-transmissible IncP plasmid in the isolate, highlighting that mcr-3 may have widely spread.

scholarly journals Identification of a Novel NDM Variant, NDM-13, from a Multidrug-Resistant Escherichia coli Clinical Isolate in Nepal

2015 ◽  
Vol 59 (9) ◽  
pp. 5847-5850 ◽  
Author(s):  
Basudha Shrestha ◽  
Tatsuya Tada ◽  
Tohru Miyoshi-Akiyama ◽  
Kayo Shimada ◽  
Hiroshi Ohara ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Enzymatic Activity ◽  
Clinical Isolate ◽  
Multidrug Resistant ◽  
New Delhi ◽  
Content Type ◽  
Genetic Environment ◽  
Carbapenem Resistant

ABSTRACTA novel New Delhi metallo-β-lactamase, NDM-13, was identified in a carbapenem-resistantEscherichia coliclinical isolate obtained from the urine of a patient in Nepal. The enzymatic activity of NDM-13 against β-lactams was similar to that of NDM-1. However, NDM-13 displayed significantly higherkcat/Kmratios for cefotaxime. The genetic environment ofblaNDM-13was determined to betnpA-IS30-blaNDM-13-bleMBL-trpF-dsbC-cutA-groES-groL, withblaNDM-13located within the chromosome.

scholarly journals Plasmid-Mediated Novel blaNDM-17 Gene Encoding a Carbapenemase with Enhanced Activity in a Sequence Type 48 Escherichia coli Strain

2017 ◽  
Vol 61 (5) ◽  
Author(s):  
Zhihai Liu ◽  
Yang Wang ◽  
Timothy R. Walsh ◽  
Dejun Liu ◽  
Zhangqi Shen ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Treatment Options ◽  
Coli Strain ◽  
Sequence Type ◽  
Animal Origin ◽  
New Delhi ◽  
Gene Encoding ◽  
Content Type ◽  
Carbapenem Resistant

ABSTRACT Carbapenem-resistant Enterobacteriaceae (CRE) have spread worldwide, leaving very few treatment options available. New Delhi metallo-beta-lactamase (NDM) is the main carbapenemase mediating CRE resistance and is of increasing concern. NDM-positive Enterobacteriaceae of human origin are frequently identified; however, the emergence of NDM, and particularly novel variants, in bacteria of food animal origin has never been reported. Here, we characterize a novel NDM variant (assigned NDM-17) identified in a β-lactam-resistant sequence type 48 (ST48) Escherichia coli strain that was isolated from a chicken in China. Compared to NDM-1, NDM-17 had three amino acid substitutions (V88L, M154L, and E170K) that confer significantly enhanced carbapenemase activity. Compared to NDM-5, NDM-17 had only one amino acid substitution (E170K) and slightly increased isolate resistance to carbapenem, as indicated by increased MIC values. The gene encoding NDM-17 (bla NDM-17) was located on an IncX3 plasmid, which was readily transferrable to recipient E. coli strain J53 by conjugation, suggesting the possibility of the rapid dissemination of bla NDM-17. Enzyme kinetics showed that NDM-17 could hydrolyze all β-lactams tested, except for aztreonam, and had a significantly higher affinity for all β-lactams tested than did NDM-5. The emergence of this novel NDM variant could pose a threat to public health because of its transferability and enhanced carbapenemase activity.

scholarly journals IMP-51, a Novel IMP-Type Metallo-β-Lactamase with Increased Doripenem- and Meropenem-Hydrolyzing Activities, in a Carbapenem-Resistant Pseudomonas aeruginosa Clinical Isolate

2015 ◽  
Vol 59 (11) ◽  
pp. 7090-7093 ◽  
Author(s):  
Tatsuya Tada ◽  
Pham Hong Nhung ◽  
Tohru Miyoshi-Akiyama ◽  
Kayo Shimada ◽  
Doan Mai Phuong ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Amino Acid ◽  
Clinical Isolate ◽  
Amino Acid Residue ◽  
Active Site ◽  
Medical Setting ◽  
Content Type ◽  
E Coli ◽  
Carbapenem Resistant

ABSTRACTA meropenem-resistantPseudomonas aeruginosaisolate was obtained from a patient in a medical setting in Hanoi, Vietnam. The isolate was found to have a novel IMP-type metallo-β-lactamase, IMP-51, which differed from IMP-7 by an amino acid substitution (Ser262Gly).Escherichia coliexpressingblaIMP-51showed greater resistance to cefoxitin, meropenem, and moxalactam thanE. coliexpressingblaIMP-7. The amino acid residue at position 262 was located near the active site, proximal to the H263 Zn(II) ligand.

scholarly journals Amino Acid Substitutions of CrrB Responsible for Resistance to Colistin through CrrC in Klebsiella pneumoniae

2016 ◽  
Vol 60 (6) ◽  
pp. 3709-3716 ◽  
Author(s):  
Yi-Hsiang Cheng ◽  
Tzu-Lung Lin ◽  
Yi-Tsung Lin ◽  
Jin-Town Wang
Keyword(s):  
Amino Acid ◽  
Klebsiella Pneumoniae ◽  
Site Directed Mutagenesis ◽  
Amino Acid Substitutions ◽  
Missense Mutations ◽  
Colistin Resistance ◽  
Two Component System ◽  
Content Type ◽  
Carbapenem Resistant ◽  
Elevated Expression

Colistin is a last-resort antibiotic for treatment of carbapenem-resistantKlebsiella pneumoniae. A recent study indicated that missense mutations in the CrrB protein contribute to colistin resistance. In our previous study, mechanisms of colistin resistance were defined in 17 of 26 colistin-resistantK. pneumoniaeclinical isolates. Of the remaining nine strains, eight were highly resistant to colistin. In the present study,crrABsequences were determined for these eight strains. Six separate amino acid substitutions in CrrB (Q10L, Y31H, W140R, N141I, P151S, and S195N) were detected. Site-directed mutagenesis was used to generatecrrBloci harboring individual missense mutations; introduction of the mutated genes into a susceptible strain, A4528, resulted in 64- to 1,024-fold increases in colistin MICs. ThesecrrBmutants showed increased accumulation ofH239_3062,H239_3059,pmrA,pmrC, andpmrHtranscripts by quantitative reverse transcription (qRT)-PCR. Deletion ofH239_3062(but not that ofH239_3059) in the A4528crrB(N141I) strain attenuated resistance to colistin, andH239_3062was accordingly namedcrrC. Similarly, accumulation ofpmrA,pmrC, andpmrHtranscripts induced bycrrB(N141I) was significantly attenuated upon deletion ofcrrC. Complementation ofcrrCrestored resistance to colistin and accumulation ofpmrA,pmrC, andpmrHtranscripts in acrrB(N141I) ΔcrrCstrain. In conclusion, novel individual CrrB amino acid substitutions (Y31H, W140R, N141I, P151S, and S195N) were shown to be responsible for colistin resistance. We hypothesize that CrrB mutations induce CrrC expression, thereby inducing elevated expression of thepmrHFIJKLMoperon andpmrC(an effect mediated via the PmrAB two-component system) and yielding increased colistin resistance.

scholarly journals Biochemical Analysis of Metallo-β-Lactamase NDM-3 from a Multidrug-Resistant Escherichia coli Strain Isolated in Japan

2014 ◽  
Vol 58 (6) ◽  
pp. 3538-3540 ◽  
Author(s):  
Tatsuya Tada ◽  
Tohru Miyoshi-Akiyama ◽  
Kayo Shimada ◽  
Teruo Kirikae
Keyword(s):  
Escherichia Coli ◽  
Biochemical Analysis ◽  
Multidrug Resistant ◽  
Coli Strain ◽  
Enzymatic Activities ◽  
New Delhi ◽  
Content Type ◽  
Genetic Context

ABSTRACTNew Delhi metallo-β-lactamase-3 (NDM-3) was identified in a multidrug-resistantEscherichia coliisolate, NCGM77, obtained from the feces of a patient in Japan. The enzymatic activities of NDM-3 against β-lactams were similar to those of NDM-1, although NDM-3 showed slightly lowerkcat/Kmratios for all the β-lactams tested except for doripenem. The genetic context forblaNDM-3wastnpA-blaNDM-3-bleMBL-trpF-dsbC-tnpA-sulI-qacEdeltaI-aadA2-dfrA1, which was present on an approximately 250-kb plasmid.

scholarly journals Outbreak Caused by Enterobacteriaceae Harboring NDM-1 Metallo-β-Lactamase Carried in an IncFII Plasmid in a Tertiary Care Hospital in Mexico City

2015 ◽  
Vol 59 (11) ◽  
pp. 7080-7083 ◽  
Author(s):  
Pedro Torres-González ◽  
Miriam Bobadilla-del Valle ◽  
Estrella Tovar-Calderón ◽  
Francisco Leal-Vega ◽  
Araceli Hernández-Cruz ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Mexico City ◽  
Tertiary Care Hospital ◽  
Bacterial Species ◽  
Tertiary Care ◽  
Enterobacter Cloacae ◽  
New Delhi ◽  
Care Hospital ◽  
Content Type ◽  
Carbapenem Resistant

ABSTRACTCarbapenem-resistantEnterobacteriaceaecarrying New Delhi metallo-β-lactamase 1 (NDM-1) have rarely been reported in Latin America. We report of an outbreak caused by ablaNDM-1-harboring plasmid spread through different bacterial species, includingEscherichia coli(ST617) andEnterobacter cloacae(ST182) isolates from the same patient and threeKlebsiella pneumoniaeisolates (ST22) derived from three epidemiologically related patients. IncFII plasmids were found in all strains. Measures to control the outbreak were applied successfully.

scholarly journals NDM-4 Metallo-β-Lactamase with Increased Carbapenemase Activity from Escherichia coli

2012 ◽  
Vol 56 (4) ◽  
pp. 2184-2186 ◽  
Author(s):  
Patrice Nordmann ◽  
Anne E. Boulanger ◽  
Laurent Poirel
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Amino Acid Substitution ◽  
Active Sites ◽  
Hydrolytic Activity ◽  
Single Amino Acid Substitution ◽  
Single Amino Acid ◽  
Amino Acid Substitutions ◽  
Content Type

ABSTRACTA clinicalEscherichia coliisolate resistant to all β-lactams, including carbapenems, expressed a novel metallo-β-lactamase (MBL), NDM-4, differing from NDM-1 by a single amino acid substitution (Met154Leu). NDM-4 possessed increased hydrolytic activity toward carbapenems and several cephalosporins compared to that of NDM-1. This amino acid substitution was not located in the known active sites of NDM-1, indicating that remote amino acid substitutions might also play a role in the extended activity of this MBL.

scholarly journals AmpC β-Lactamase in an Escherichia coli Clinical Isolate Confers Resistance to Expanded-Spectrum Cephalosporins

2004 ◽  
Vol 48 (10) ◽  
pp. 4050-4053 ◽  
Author(s):  
Hedi Mammeri ◽  
Hasan Nazic ◽  
Thierry Naas ◽  
Laurent Poirel ◽  
Sophie Léotard ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Clinical Isolate ◽  
Biochemical Analysis ◽  
Amino Acid Substitutions ◽  
E Coli ◽  
Extended Spectrum

ABSTRACT Cloning, sequencing, and biochemical analysis identified a novel AmpC-type β-lactamase conferring resistance to extended-spectrum cephalosporins in an Escherichia coli clinical isolate. This enzyme, exhibiting 14 amino acid substitutions compared to a reference AmpC cephalosporinase of E. coli, hydrolyzed ceftazidime and cefepime significantly.

scholarly journals A Novel New Delhi Metallo-β-Lactamase Variant, NDM-14, Isolated in a Chinese Hospital Possesses Increased Enzymatic Activity against Carbapenems

2015 ◽  
Vol 59 (4) ◽  
pp. 2450-2453 ◽  
Author(s):  
Dayang Zou ◽  
Yong Huang ◽  
Xiangna Zhao ◽  
Wei Liu ◽  
Derong Dong ◽  
...  
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Amino Acid ◽  
Intensive Care Unit Patient ◽  
Enzymatic Activity ◽  
Clinical Isolate ◽  
Kinetic Data ◽  
New Delhi ◽  
Local Hospital ◽  
Content Type

ABSTRACTA novel New Delhi metallo-β-lactamase (NDM) variant, NDM-14, was identified in clinical isolateAcinetobacter lwoffiiJN49-1, which was recovered from an intensive care unit patient at a local hospital in China. NDM-14, which differs from other existing enzymes by an amino acid substitution at position 130 (Asp130Gly), possesses enzymatic activity toward carbapenems that is greater than that of NDM-1. Kinetic data indicate that NDM-14 has a higher affinity for imipenem and meropenem.

Sign in / Sign up

Export Citation Format

Share Document