Mutations in aarE, the ubiA Homolog of Providencia stuartii, Result in High-Level Aminoglycoside Resistance and Reduced Expression of the Chromosomal Aminoglycoside 2′-N-Acetyltransferase

1998 ◽  
Vol 42 (4) ◽  
pp. 959-962 ◽  
Author(s):  
Michael R. Paradise ◽  
Gregory Cook ◽  
Robert K. Poole ◽  
Philip N. Rather
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Amino Acid Identity ◽  
Second Step ◽  
Aminoglycoside Resistance ◽  
Acid Identity ◽  
E Coli ◽  
Small Colony ◽  
Providencia Stuartii ◽  
High Level

ABSTRACT The aarE1 allele was identified on the basis of the resulting phenotype of increased aminoglycoside resistance. TheaarE1 mutation also resulted in a small-colony phenotype and decreased levels of aac(2′)-Ia mRNA. The deduced AarE gene product displayed 61% amino acid identity to theEscherichia coli UbiA protein, an octaprenyltransferase required for the second step of ubiquinone biosynthesis. Complementation experiments in both Providencia stuartiiand E. coli demonstrated that aarE andubiA are functionally equivalent.

scholarly journals PBP5, PBP6 and DacD play different roles in intrinsic β-lactam resistance of Escherichia coli

Microbiology ◽  
2011 ◽  
Vol 157 (9) ◽  
pp. 2702-2707 ◽  
Author(s):  
Sujoy Kumar Sarkar ◽  
Mouparna Dutta ◽  
Chiranjit Chowdhury ◽  
Akash Kumar ◽  
Anindya S. Ghosh
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Parent Strain ◽  
Amino Acid Identity ◽  
Enzymic Activity ◽  
Exponential Phase ◽  
Wild Type ◽  
Acid Identity ◽  
Penicillin Binding Proteins ◽  
E Coli

Escherichia coli PBP5, PBP6 and DacD, encoded by dacA, dacC and dacD, respectively, share substantial amino acid identity and together constitute ~50 % of the total penicillin-binding proteins of E. coli. PBP5 helps maintain intrinsic β-lactam resistance within the cell. To test if PBP6 and DacD play simlar roles, we deleted dacC and dacD individually, and dacC in combination with dacA, from E. coli 2443 and compared β-lactam sensitivity of the mutants and the parent strain. β-Lactam resistance was complemented by wild-type, but not dd-carboxypeptidase-deficient PBP5, confirming that enzymic activity of PBP5 is essential for β-lactam resistance. Deletion of dacC and expression of PBP6 during exponential or stationary phase did not alter β-lactam resistance of a dacA mutant. Expression of DacD during mid-exponential phase partially restored β-lactam resistance of the dacA mutant. Therefore, PBP5 dd-carboxypeptidase activity is essential for intrinsic β-lactam resistance of E. coli and DacD can partially compensate for PBP5 in this capacity, whereas PBP6 cannot.

scholarly journals Identification of FosA8, a Plasmid-Encoded Fosfomycin Resistance Determinant from Escherichia coli, and Its Origin in Leclercia adecarboxylata

2019 ◽  
Vol 63 (11) ◽  
Author(s):  
Laurent Poirel ◽  
Xavier Vuillemin ◽  
Nicolas Kieffer ◽  
Linda Mueller ◽  
Marie-Christine Descombes ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Amino Acid Identity ◽  
Natural Resistance ◽  
Whole Genome ◽  
Content Type ◽  
Acid Identity ◽  
E Coli ◽  
Fosfomycin Resistance ◽  
High Level ◽  
Level Resistance

ABSTRACT A plasmid-located fosfomycin resistance gene, fosA8, was identified from a CTX-M-15-producing Escherichia coli isolate recovered from urine. Identification of this gene was obtained by whole-genome sequencing. It encoded FosA8, which shares 79% and 78% amino acid identity with the most closely related FosA2 and FosA1 enzymes, respectively. The fosA8 gene was located on a transferable 50-kb plasmid of IncN type encoding high-level resistance to fosfomycin. In silico analysis and cloning experiments identified fosA8 analogues (99% identity) in the genome of Leclercia decarboxylata, which is an enterobacterial species with natural resistance to fosfomycin. This finding adds L. decarboxylata to the list of enterobacterial species that are a reservoir of fosA-like genes which have been captured from the chromosome of a progenitor and are then acquired by E. coli.

scholarly journals Coproduction of 16S rRNA Methyltransferase RmtD or RmtG with KPC-2 and CTX-M Group Extended-Spectrum β-Lactamases in Klebsiella pneumoniae

2013 ◽  
Vol 57 (5) ◽  
pp. 2397-2400 ◽  
Author(s):  
Maria Fernanda C. Bueno ◽  
Gabriela R. Francisco ◽  
Jessica A. O'Hara ◽  
Doroti de Oliveira Garcia ◽  
Yohei Doi
Keyword(s):  
Amino Acid ◽  
16S Rrna ◽  
Klebsiella Pneumoniae ◽  
Amino Acid Identity ◽  
Aminoglycoside Resistance ◽  
Content Type ◽  
Acid Identity ◽  
Paulo State ◽  
Extended Spectrum ◽  
High Level

ABSTRACTEightKlebsiella pneumoniaeclinical strains with high-level aminoglycoside resistance were collected from eight hospitals in São Paulo State, Brazil, in 2010 and 2011. Three of them produced an RmtD group 16S rRNA methyltransferase, RmtD1 or RmtD2. Five strains were found to produce a novel 16S rRNA methyltransferase, designated RmtG, which shared 57 to 58% amino acid identity with RmtD1 and RmtD2. Seven strains coproduced KPC-2 with or without various CTX-M group extended-spectrum β-lactamases, while the remaining strain coproduced CTX-M-2.

Functional and Structural Characterization of Acquired Pan-Aminoglycoside Resistance 16S rRNA Methyltransferase NpmB1

2021 ◽  
Author(s):  
Akito Kawai ◽  
Masahiro Suzuki ◽  
Kentaro Tsukamoto ◽  
Yusuke Minato ◽  
Yohei Doi
Keyword(s):  
Amino Acid ◽  
16S Rrna ◽  
Amino Acid Identity ◽  
Single Amino Acid ◽  
Aminoglycoside Resistance ◽  
E Coli ◽  
The United Kingdom ◽  
Amino Acid Variant ◽  
A Site

Post-translational methylation of the A site of 16S rRNA at position A1408 leads to pan-aminoglycoside resistance encompassing both 4,5- and 4,6-disubstituted 2-deoxystreptamine (DOS) aminoglycosides. To date, NpmA is the only acquired enzyme with such function. Here, we present function and structure of NpmB1 whose sequence was identified in Escherichia coli genomes registered from the United Kingdom. NpmB1 possesses 40% amino acid identity with NpmA1 and confers resistance to all clinically relevant aminoglycosides including 4,5-DOS agents. Phylogenetic analysis of NpmB1 and NpmB2, its single amino acid variant, revealed that the encoding gene was likely acquired by E. coli from a soil bacterium. The structure of NpmB1 suggests that it requires a structural change of the β6/7 linker in order to bind to 16S rRNA. These findings establish NpmB1 and NpmB2 as the second group of acquired pan-aminoglycoside resistance 16S rRNA methyltransferases.

Recombinant mouse prolactin: expression in Escherichia coli, purification and biological activity

1992 ◽  
Vol 8 (2) ◽  
pp. 165-172 ◽  
Author(s):  
M. Yamamoto ◽  
T. Harigaya ◽  
T. Ichikawa ◽  
K. Hoshino ◽  
K. Nakashima
Keyword(s):  
Escherichia Coli ◽  
Biological Activity ◽  
Amino Acid ◽  
Multicopy Plasmid ◽  
High Level Expression ◽  
E Coli ◽  
Expression In Escherichia Coli ◽  
Oligonucleotide Duplex ◽  
Efficient Expression ◽  
High Level

ABSTRACT Transformation of Escherichia coli cells with a recombinant plasmid containing modified mouse prolactin (mPRL) cDNA and a pKK223-3 vector resulted in efficient expression of mPRL protein. Cloned mPRL cDNA was modified by removing the 5′ non-translating sequence as well as the sequence which encoded the signal peptide of preprolactin for recombination. In addition, approximately 100 nucleotides of the 5′-terminal region of the cDNA, which include the ATG initiation codon and the following 31 codons of mature mPRL, were replaced by a chemically synthesized oligonucleotide duplex. The sequence of this duplex was chosen to be rich in AT without changing the amino acid sequence of the protein. The modified cDNA was finally inserted into the multicopy plasmid, pUC19, before high-level expression of mPRL in E. coli cells was obtained. Western blotting analysis of total protein from transformed E. coli cells showed that both 23 and 16kDa peptides were recognized by specific mPRL antisera. The purified and refolded 23 kDa protein exhibited a growth-stimulating effect on rat Nb 2 Node lymphoma cells, and was very similar to that of natural pituitary PRL.

scholarly journals Chromosome-Encoded Ambler Class D β-Lactamase of Shewanella oneidensis as a Progenitor of Carbapenem-Hydrolyzing Oxacillinase

2004 ◽  
Vol 48 (1) ◽  
pp. 348-351 ◽  
Author(s):  
Laurent Poirel ◽  
Claire Héritier ◽  
Patrice Nordmann
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Klebsiella Pneumoniae ◽  
Reference Strain ◽  
Shewanella Oneidensis ◽  
Amino Acid Identity ◽  
Gram Negative ◽  
Acid Identity ◽  
Class D ◽  
Lactamase Gene

ABSTRACT A chromosome-encoded β-lactamase gene from a Shewanella oneidensis reference strain was cloned and expressed in Escherichia coli. It encoded a carbapenem-hydrolyzing Ambler class D β-lactamase, OXA-54, that shared 92% amino acid identity with the plasmid-encoded carbapenem-hydrolyzing oxacillinase OXA-48 from Klebsiella pneumoniae. This work suggests that Shewanella spp. may produce the progenitor of oxacillinases compromising the efficacy of imipenem in clinically relevant gram-negative pathogens.

scholarly journals Cloning of a Novel Gene for Quinolone Resistance from a Transferable Plasmid in Shigella flexneri 2b

2005 ◽  
Vol 49 (2) ◽  
pp. 801-803 ◽  
Author(s):  
Mami Hata ◽  
Masahiro Suzuki ◽  
Masakado Matsumoto ◽  
Masao Takahashi ◽  
Katsuhiko Sato ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Clinical Isolate ◽  
Shigella Flexneri ◽  
Amino Acid Identity ◽  
Quinolone Resistance ◽  
Acid Identity ◽  
Low Level ◽  
Novel Gene ◽  
Level Resistance

ABSTRACT A novel gene for quinolone resistance was cloned from a transferable plasmid carried by a clinical isolate of Shigella flexneri 2b that was resistant to fluoroquinolones. The plasmid conferred low-level resistance to quinolones on Escherichia coli HB101. The protein encoded by the gene showed 59% amino acid identity with Qnr.

FeoB is not required for ferrous iron uptake inCampylobacter jejuni

2003 ◽  
Vol 49 (11) ◽  
pp. 727-731 ◽  
Author(s):  
Brian H Raphael ◽  
Lynn A Joens
Keyword(s):  
Escherichia Coli ◽  
Helicobacter Pylori ◽  
Campylobacter Jejuni ◽  
Ferrous Iron ◽  
Iron Uptake ◽  
No Reduction ◽  
Amino Acid Identity ◽  
Acid Identity ◽  
E Coli ◽  
Magnesium Transporter

Among strains of Campylobacter jejuni, levels of ferrous iron (Fe2+) uptake was comparable. However, C. jejuni showed a lower level of ferrous iron uptake than Escherichia coli. Consistent with studies of E. coli, Fe2+uptake in C. jejuni was significantly enhanced by low Mg2+concentration. The C. jejuni genome sequence contains a single known ferrous iron uptake gene, feoB, whose product shares 50% amino acid identity to Helicobacter pylori FeoB and 29% identity to E. coli FeoB. However, Fe2+uptake could not be attributed to FeoB for several reasons. Site-directed mutations in feoB caused no defect in55Fe2+uptake. Among C. jejuni strains, various nucleotide alterations were found in feoB, indicating that some C. jejuni feoB genes are defective. In addition, uptake could not be attributed to the magnesium transporter CorA, since no reduction in55Fe2+uptake was observed in the presence of a CorA-specific inhibitor.Key words: Campylobacter jejuni, ferrous iron uptake, metal transport, FeoB.

scholarly journals Interference between avian endogenous ev/J 4.1 and exogenous ALV-J retroviral envelopes

2003 ◽  
Vol 84 (12) ◽  
pp. 3233-3238 ◽  
Author(s):  
Caroline Denesvre ◽  
Denis Soubieux ◽  
Gaelle Pin ◽  
Dominique Hue ◽  
Ginette Dambrine
Keyword(s):  
Amino Acid ◽  
Envelope Protein ◽  
Avian Leukosis Virus ◽  
Amino Acid Identity ◽  
Acid Identity ◽  
New Family ◽  
Endogenous Sequence ◽  
High Level

A new family of avian retroviral endogenous sequences designated ev/J or EAV-HP has been identified recently. Here an additional avian ev/J 4.1 endogenous sequence, ev/J 4.1 Rb, is reported. ev/J 4.1 Rb has the most extensive amino acid identity ever described for an endogenous envelope protein with the ALV-J avian leukosis virus. Here, we also demonstrate that ev/J 4.1 Rb functionally pseudotypes murine leukaemia virions and leads to a complete reciprocal interference with ALV-J envelopes. This is the first demonstration of such a high level of envelope interference between endogenous and exogenous avian retroviruses. Our results provide additional clues on the co-evolution of retroviral sequences among vertebrates.

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