scholarly journals Identification of a Novel β-Lactamase Produced byXanthomonas campestris, a Phytopathogenic Bacterium

1999 ◽  
Vol 43 (7) ◽  
pp. 1792-1797 ◽  
Author(s):  
Shu-Fen Weng ◽  
Chun-Yi Chen ◽  
Yeong-Sheng Lee ◽  
Juey-Wen Lin ◽  
Yi-Hsiung Tseng
Keyword(s):  
Amino Acid ◽  
Stenotrophomonas Maltophilia ◽  
Xanthomonas Campestris ◽  
Southern Hybridization ◽  
Gene Replacement ◽  
Phytopathogenic Bacterium ◽  
Class A ◽  
Homologous Fragment ◽  
Group 2 ◽  
Lactamase Gene

ABSTRACT The Xanthomonas campestris pv. campestris 11 chromosome encodes a periplasmic β-lactamase of 30 kDa. Gene replacement and complementation confirmed the presence of this enzyme. Its deduced amino acid sequence shows identity and conserved domains between it andStenotrophomonas maltophilia L2 and other Ambler class A/Bush group 2 β-lactamases. Southern hybridization detected a single homologous fragment in each of 12 other Xanthomonasstrains, indicating that the presence of a β-lactamase gene is common among xanthomonads.

scholarly journals Constitutive Expression of a Chromosomal Class A (BJM Group 2) β-Lactamase in Xanthomonas campestris

2004 ◽  
Vol 48 (1) ◽  
pp. 209-215 ◽  
Author(s):  
Shu-Fen Weng ◽  
Juey-Wen Lin ◽  
Chih-Hung Chen ◽  
Yih-Yuan Chen ◽  
Yi-Hsuan Tseng ◽  
...  
Keyword(s):  
Amino Acid ◽  
Xanthomonas Campestris ◽  
Southern Hybridization ◽  
Constitutive Expression ◽  
Structural Features ◽  
Amino Acid Identity ◽  
Upstream Region ◽  
Class A ◽  
Group 2 ◽  
Lactamase Gene

ABSTRACT Sequencing of the upstream region of the β-lactamase gene from Xanthomonas campestris pv. campestris 11 (bla XCC-1) revealed the cognate ampR1 gene (289 amino acids, 31 kDa). It runs divergently from bla XCC-1 with a 100-bp intergenic region (IG) containing partially overlapped promoters with structural features typical of the bla-ampR IG. The deduced AmpR1 protein shows significant identity in amino acid sequence and conserved motifs with AmpR proteins of other species, e.g., of Pseudomonas aeruginosa (58.2% amino acid identity). Results of insertional mutation, complementation tests, and β-lactamase assays suggested that expression of bla XCC-1 was constitutive and dependent on AmpR1. Four bla genes and two ampR genes are present in the fully sequenced X. campestris pv. campestris ATCC 33913 genome, with XCC3039 and XCC3040 considered the analogues of bla XCC-1 and ampR1, respectively. An ampR1 homologue was detected by Southern hybridization in the ampicillin-resistant Xanthomonas strains, which appear to express β-lactamase constitutively. Although the significance remains to be studied, constitutive expression of β-lactamase by a widespread bacterial genus raises environmental concerns regarding the dissemination of resistance genes.

scholarly journals Chromosome-Borne Class A BOR-1 β-Lactamase of Bordetella bronchiseptica and Bordetella parapertussis

2005 ◽  
Vol 49 (6) ◽  
pp. 2565-2567 ◽  
Author(s):  
Marie-Frédérique Lartigue ◽  
Laurent Poirel ◽  
Nicolas Fortineau ◽  
Patrice Nordmann
Keyword(s):  
Amino Acid ◽  
Clavulanic Acid ◽  
Stenotrophomonas Maltophilia ◽  
Amino Acid Identity ◽  
Bordetella Bronchiseptica ◽  
Bordetella Parapertussis ◽  
Acid Identity ◽  
Class A ◽  
Lactamase Gene ◽  
Reference Strains

ABSTRACT A narrow-spectrum clavulanic acid-inhibited class A β-lactamase, BOR-1, was identified in a Bordetella bronchiseptica clinical isolate. It shared 45% amino acid identity with L-2 from Stenotrophomonas maltophilia. An identical β-lactamase gene was found in B. bronchiseptica and Bordetella parapertussis reference strains that may contribute only in part to their resistance phenotype.

scholarly journals GES-2, a Class A β-Lactamase fromPseudomonas aeruginosa with Increased Hydrolysis of Imipenem

2001 ◽  
Vol 45 (9) ◽  
pp. 2598-2603 ◽  
Author(s):  
Laurent Poirel ◽  
Gerhard F. Weldhagen ◽  
Thierry Naas ◽  
Christophe De Champs ◽  
Michael G. Dove ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Amino Acid ◽  
Amino Acid Change ◽  
Blood Cultures ◽  
Class A ◽  
Omega Loop ◽  
Cephalosporin Resistance ◽  
Lactamase Gene ◽  
Hydrolysis Of

ABSTRACT Pseudomonas aeruginosa GW-1 was isolated in 2000 in South Africa from blood cultures of a 38-year-old female who developed nosocomial pneumonia. This isolate harbored a self-transferable ca. 100-kb plasmid that conferred an expanded-spectrum cephalosporin resistance profile associated with an intermediate susceptibility to imipenem. A β-lactamase gene, bla GES-2, was cloned from whole-cell DNA of P. aeruginosa GW-1 and expressed in Escherichia coli. GES-2, with a pI value of 5.8, hydrolyzed expanded-spectrum cephalosporins, and its substrate profile was extended to include imipenem compared to that of GES-1, identified previously in Klebsiella pneumoniae. GES-2 activity was less inhibited by clavulanic acid, tazobactam and imipenem than GES-1. The GES-2 amino acid sequence differs from that of GES-1 by a glycine-to-asparagine substitution in position 170 located in the omega loop of Ambler class A enzymes. This amino acid change may explain the extension of the substrate profile of the plasmid-encoded β-lactamase GES-2.

scholarly journals Characterization of beta-lactamase gene blaPER-2, which encodes an extended-spectrum class A beta-lactamase.

1996 ◽  
Vol 40 (3) ◽  
pp. 616-620 ◽  
Author(s):  
A Bauernfeind ◽  
I Stemplinger ◽  
R Jungwirth ◽  
P Mangold ◽  
S Amann ◽  
...  
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequence ◽  
Beta Lactamase ◽  
Reading Frame ◽  
Beta Lactamases ◽  
Class A ◽  
Extended Spectrum ◽  
The Family ◽  
Extended Spectrum Beta Lactamases ◽  
Lactamase Gene

Plasmidic extended-spectrum beta-lactamases of Ambler class A are mostly inactive against ceftibuten. Salmonella typhimurium JMC isolated in Argentina harbors a bla gene located on a plasmid (pMVP-5) which confers transferable resistance to oxyiminocephalosporins, aztreonam, and ceftibuten. The beta-lactamase PER-2 (formerly ceftibutenase-1; CTI-1) is highly susceptible to inhibition by clavulanate and is located at a pI of 5.4 after isoelectric focusing. The blaPER-2 gene was cloned and sequenced. The nucleotide sequence of a 2.2-kb insert in vector pBluescript includes an open reading frame of 927 bp. Comparison of the deduced amino acid sequence of PER-2 with those of other beta-lactamases indicates that PER-2 is not closely related to TEM or SHV enzymes (25 to 26% homology). PER-2 is most closely related to PER-1 (86.4% homology), an Ambler class A enzyme first detected in Pseudomonas aeruginosa. An enzyme with an amino acid sequence identical to that of PER-1, meanwhile, was found in various members of the family Enterobacteriaceae isolated from patients in Turkey. Our data indicate that PER-2 and PER-1 represent a new group of Ambler class A extended-spectrum beta-lactamases. PER-2 so far has been detected only in pathogens (S. typhimurium, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis) isolated from patients in South America, while the incidence of PER-1-producing strains so far has been restricted to Turkey, where it occurs both in members of the family Enterobacteriaceae and in P. aeruginosa.

scholarly journals An allelic variant of the chromosomal gene for class A beta-lactamase K2, specific for Klebsiella pneumoniae, is the ancestor of SHV-1.

1997 ◽  
Vol 41 (12) ◽  
pp. 2705-2709 ◽  
Author(s):  
S Haeggman ◽  
S Löfdahl ◽  
L G Burman
Keyword(s):  
Sequence Data ◽  
Negative Resistance ◽  
Beta Lactamase ◽  
Beta Lactams ◽  
Beta Lactamases ◽  
Class A ◽  
Cephalosporin Resistance ◽  
Group 2 ◽  
Lactamase Gene ◽  
Type Strains

Fecal Klebsiella isolates from neonates in 22 Swedish special care units were examined by a PCR we developed for detection of the SHV-1 beta-lactamase gene. All 105 K. pneumoniae isolates and all 11 K. pneumoniae reference strains (including the K. pneumoniae subsp. pneumoniae, ozaenae, and rhinoscleromatis type strains) tested were positive, whereas all 67 K. oxytoca isolates and the K. oxytoca, K. planticola, and K. terrigena type strains tested were negative. Resistance to beta-lactams in K. pneumoniae was not transferable by conjugation, and the beta-lactamase gene was never found on a plasmid. Southern blot analysis showed that the gene had a defined chromosomal location. Isoelectric focusing and sequencing of 231-bp PCR amplicons from different isolates revealed many variants of the enzyme, with the two main groups being SHV-1 like (pI 7.6; 68 isolates) and LEN-1 like (pI 7.1; 14 isolates). Clavulanic acid markedly reduced the MICs of ampicillin for all the K. pneumoniae isolates tested. This fact, MIC profiles (penicillin rather than cephalosporin resistance), pIs, and sequence data showed that the chromosomal beta-lactamase of K. pneumoniae is a class A, group 2 enzyme distinct from the chromosomal AmpC enzymes found in several other gram-negative bacteria and from the chromosomal beta-lactamase K1 of K. oxytoca. We propose that the chromosomal beta-lactamase of K. pneumoniae be designated K2 and suggest that an allelic pI 7.6 variant of this enzyme is the ancestor of the SHV family of plasmid-mediated beta-lactamases.

scholarly journals Chromosome-Encoded Ambler Class A β-Lactamase of Kluyvera georgiana, a Probable Progenitor of a Subgroup of CTX-M Extended-Spectrum β-Lactamases

2002 ◽  
Vol 46 (12) ◽  
pp. 4038-4040 ◽  
Author(s):  
Laurent Poirel ◽  
Peter Kämpfer ◽  
Patrice Nordmann
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Reference Strain ◽  
Amino Acid Identity ◽  
Acid Identity ◽  
Class A ◽  
Extended Spectrum ◽  
Lactamase Gene

ABSTRACT A chromosome-encoded β-lactamase gene, cloned and expressed in Escherichia coli from Kluyvera georgiana reference strain CUETM 4246-74 (DSM 9408), encoded the extended-spectrum β-lactamase KLUG-1, which shared 99% amino acid identity with the plasmid-mediated β-lactamase CTX-M-8. This work provides further evidence that Kluyvera spp. may be the progenitor(s) of CTX-M-type β-lactamases.

scholarly journals Characterization of a Chromosomally Encoded Extended-Spectrum Class A β-Lactamase from Kluyvera cryocrescens

2001 ◽  
Vol 45 (12) ◽  
pp. 3595-3598 ◽  
Author(s):  
Jean W. Decousser ◽  
Laurent Poirel ◽  
Patrice Nordmann
Keyword(s):  
Amino Acid ◽  
Reference Strain ◽  
Amino Acid Identity ◽  
Acid Identity ◽  
Class A ◽  
Extended Spectrum ◽  
Kluyvera Ascorbata ◽  
Lactamase Gene ◽  
Kluyvera Cryocrescens

ABSTRACT A chromosomally located β-lactamase gene, cloned and expressed inEscherichia coli from a reference strain of the enterobacterial species Kluyvera cryocrescens, encoded a clavulanic acid-inhibited Ambler class A enzyme, KLUC-1, with a pI value of 7.4. KLUC-1 shared 86% amino acid identity with a subgroup of plasmid-mediated CTX-M-type extended-spectrum β-lactamases (CTX-M-1, -3, -10, -11, and -12), the most closely related enzymes, and 77% amino acid identity with KLUA-1 from Kluyvera ascorbata.The substrate profile of KLUC-1 corresponded to that of CTX-M-type enzymes.

scholarly journals Amino acid sequence of the penicillin-binding protein/dd-peptidase of Streptomyces K15. Predicted secondary structures of the low Mr penicillin-binding proteins of class A

1991 ◽  
Vol 279 (1) ◽  
pp. 223-230 ◽  
Author(s):  
P Palomeque-Messia ◽  
S Englebert ◽  
M Leyh-Bouille ◽  
M Nguyen-Distèche ◽  
C Duez ◽  
...  
Keyword(s):  
Amino Acid ◽  
Amino Acid Residue ◽  
Active Sites ◽  
Binding Protein ◽  
Secondary Structures ◽  
Peptide Sequence ◽  
Penicillin Binding Protein ◽  
Signal Peptide Sequence ◽  
Beta Lactamases ◽  
Class A

The low-Mr penicillin-binding protein (PBP)/DD-transpeptidase of Streptomyces K15 is synthesized in the form of a 291-amino acid-residue precursor possessing a cleavable 29-amino acid-residue signal peptide. Sequence-similarity searches and hydrophobic-cluster analysis show that the Streptomyces K15 enzyme, the Escherichia coli PBPs/DD-carboxy-peptidases 5 and 6, the Bacillus subtilis PBP/DD-carboxypeptidase 5 and the spoIIA product (a putative PBP involved in the sporulation of B. subtilis) are structurally related and form a distinct class A of low-Mr PBPs/DD-peptidases. The distribution of the hydrophobic clusters along the amino acid sequences also shows that the Streptomyces K15 PBP, and by extension the other PBPs of class A, have similarity in the polypeptide folding, with the beta-lactamases of class A, with as reference the Streptomyces albus G and Staphylococcus aureus beta-lactamases of known three-dimensional structure. This comparison allows one to predict most of the secondary structures in the PBPs and the amino acid motifs that define the enzyme active sites.

scholarly journals A Technique for Precise Inoculation of the Internal Phyllosphere of Cotton with Xanthomonas campestris pv. malvacearum

2003 ◽  
Vol 93 (10) ◽  
pp. 1204-1208 ◽  
Author(s):  
N. Kangatharalingam ◽  
Margaret L. Pierce ◽  
Margaret Essenberg
Keyword(s):  
Xanthomonas Campestris ◽  
Bacterial Population ◽  
Guard Cells ◽  
Distilled Water ◽  
Circular Area ◽  
Phytopathogenic Bacterium ◽  
Spongy Mesophyll ◽  
Adaxial Surface ◽  
Custom Made ◽  
Palisade Cells

A technique was developed to inoculate uniformly and gently the internal phyllosphere from the upper surface of cotton leaves with the phytopathogenic bacterium Xanthomonas campestris pv. malvacearum. The inoculum consisted of 2 to 3 × 107 CFU/ml in CaCO3-saturated sterile distilled water containing 0.02%, vol/vol, of the wetting agent Silwet L-77. A custom-made inoculation apparatus was employed to immerse a circular area of the adaxial surface of a leaf in inoculum for 90 s. This resulted in uniform, passive entry of bacteria into the substomatal chambers, producing an endophytic bacterial population of 2 × 104 CFU/cm2. Microscopic signs of infection were visible 48 to 72 h after inoculation. In susceptible leaves, uniformly distributed water-soaked spots were observed 7 to 8 days after inoculation. When the technique was used on resistant leaves, the autofluorescence that is characteristic of hypersensitively necrotic cells developed in the guard cells and palisade cells lining substomatal chambers, but not in the underlying spongy mesophyll.

Sign in / Sign up

Export Citation Format

Share Document