scholarly journals Detection of New arr-4 and arr-5 Gene Cassettes in Clinical Pseudomonas aeruginosa and Klebsiella pneumoniae Strains from Brazil

2008 ◽  
Vol 52 (5) ◽  
pp. 1865-1867 ◽  
Author(s):  
Érica Lourenço da Fonseca ◽  
Fernanda dos Santos Freitas ◽  
José Carlos de Amorim ◽  
Ana Carolina Paulo Vicente
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Klebsiella Pneumoniae ◽  
American Continent ◽  
Gene Cassettes ◽  
Class 1 Integrons ◽  
Class 1

ABSTRACT New arr alleles emerged in class 1 integrons from a clinical Pseudomonas aeruginosa strain (arr-4) and four Klebsiella pneumoniae strains (arr-5) in Brazil/American continent. arr-4 was preceded by aacA7-catB3, whereas arr-5 was the unique cassette. The putative proteins shared 75% (Arr-5) and 78% (Arr-4) identities with Arr-2.

scholarly journals Class 1 Integron Containing a New Gene Cassette, aadA10, Associated with Tn1404 from R151

2002 ◽  
Vol 46 (8) ◽  
pp. 2400-2408 ◽  
Author(s):  
Sally R. Partridge ◽  
Christina M. Collis ◽  
Ruth M. Hall
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Gene Cassette ◽  
Class 1 Integron ◽  
Gene Cassettes ◽  
Base Element ◽  
Class 1 Integrons ◽  
Resistance Determinants ◽  
Class 1 ◽  
New Gene

ABSTRACT The carbenicillin, gentamicin, kanamycin, streptomycin, spectinomycin, sulfonamide, and tobramycin resistance determinants found on Pseudomonas aeruginosa plasmid R151 have previously been shown to translocate to another plasmid, R388, and it was inferred that a transposon, Tn1404, carried the resistance determinants. Sequencing of the cassette array from the plasmid known as R388::Tn1404 revealed two known gene cassettes, oxa10 and aadB, and a previously unidentified cassette determining resistance to streptomycin and spectinomycin, here designated aadA10, in the order oxa10-aadB-aadA10. These cassettes replaced the dfrB2-orfA cassette array of R388, indicating that movement of the resistance determinants from R151 to R388 resulted from recombinational exchange between two class 1 integrons rather than transposition. The AadA10 protein is most closely related to AadA6 (85% identical) and AadA7 (80% identical). The aadA10 cassette found here has only a simple site containing a 7-bp spacer derived from attI1 in place of a 59-base element and is likely to represent a derivative of the complete cassette. IntI1-mediated deletion of the aadA10 cassette was not detected, indicating that this single simple site is either inactive or only weakly active.

scholarly journals Characterization and Movement of the Class 1 Integron Known as Tn2521 and Tn1405

2002 ◽  
Vol 46 (5) ◽  
pp. 1288-1294 ◽  
Author(s):  
Sally R. Partridge ◽  
Heidi J. Brown ◽  
Ruth M. Hall
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Homologous Recombination ◽  
Complete Sequence ◽  
Class 1 Integron ◽  
Gene Cassettes ◽  
Class 1 Integrons ◽  
Single Location ◽  
Class 1 ◽  
Backbone Structure

ABSTRACT Two putative transposons, Tn2521 and Tn1405, carrying determinants for the PSE-4 β-lactamase and for resistance to streptomycin, spectinomycin, and sulfonamides were previously isolated from the chromosome of Pseudomonas aeruginosa Dalgleish. Detailed mapping and determination of the complete sequence of Tn2521 revealed that it is a class 1 integron, here renamed In33, with a backbone structure identical to that of In4 from Tn1696. In33 contains two gene cassettes, blaP1 and aadA1, replacing the aacC1-orfE-aadA2-cmlA1 cassette array in In4. Although In33 does not include any transposition genes, movement of In33 (Tn2521) targeted to a single location in the IncP-1 plasmid R18-18 has been reported previously (M. I. Sinclair and B. W. Holloway, J. Bacteriol. 151:569-579, 1982). A 5-bp duplication of the target, which lies within the res site recognized by the ParA resolvase of R18-18, was present, indicating that the mechanism of movement was transposition. Together, these data indicate that class 1 integrons that are defective in self-transposition can move under appropriate circumstances. The Tn1405 isolate studied was found to represent only the cassette array of In33, which had replaced the cassette array in the recipient plasmid R388, probably by homologous recombination.

scholarly journals Structural Diversity of Class 1 Integrons and Their Associated Gene Cassettes in Klebsiella pneumoniae Isolates from a Hospital in China

PLoS ONE ◽  
2013 ◽  
Vol 8 (9) ◽  
pp. e75805 ◽  
Author(s):  
Bin Li ◽  
Yongfei Hu ◽  
Qi Wang ◽  
Yong Yi ◽  
Patrick C. Y. Woo ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Structural Diversity ◽  
Gene Cassettes ◽  
Class 1 Integrons ◽  
Class 1

Antibiotic selective pressure for the maintenance of antibiotic resistant genes in coliform bacteria isolated from the aquatic environment

2003 ◽  
Vol 47 (3) ◽  
pp. 249-253 ◽  
Author(s):  
J.C. Park ◽  
J.C. Lee ◽  
J.Y. Oh ◽  
Y.W. Jeong ◽  
J.W. Cho ◽  
...  
Keyword(s):  
Aquatic Environment ◽  
Selective Pressure ◽  
Functional Class ◽  
Coliform Bacteria ◽  
Antibiotic Resistant ◽  
Gene Cassettes ◽  
Class 1 Integrons ◽  
Selective Pressures ◽  
Class 1 ◽  
Inti1 Gene

Coliform bacteria isolated from the aquatic environment were investigated for antibiotic susceptibility and detailed structures of class 1 integrons. A high proportion of isolates were found to be resistant to sulfamethoxazole, aminoglycosides, and β-lactams. The 750 (53.6%) isolates were resistant to one or more of the antibiotics tested out of 1,400 coliform bacteria. Based on the MIC of antibiotics and antibiogram, 150 isolates were selected and further studied for class 1 integrons. The intI1 gene was found in 36 (24.0%) of the 150 isolates. Twelve isolates carried the gene cassettes responsible for antibiotic resistance, while no gene cassettes were found in 24 isolates. Seven different genes, dfrA5, dfrA7, dfrA12, dfrA17, aaA2, aaA5, and aad(3’), were detected in gene cassettes. The dfrA and aad genes located on class 1 integrons were responsible for resistance to trimethoprim and aminoglycosides. The remaining 24 coliform bacteria had the incomplete or non-functional class 1 integrons. These results indicated that antibiotic selective pressures may play an important role to maintain gene cassettes of class 1 integrons and in the absence of sustained antibiotic pressures, such as the aquatic environment, coliform bacteria may carry empty or non-functional class 1 integrons.

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