Diversity of resistance phenotypes and plasmid analysis in multi-resistant 0:12 Pseudomonas aeruginosa

Abstract

Antibiotic resistance phenotypes, plasmid content and ability of conjugal transfer of antibiotic resistance genes of 35 multi-resistant Pseudomonas aeruginosa strains were examined. The strains were isolated in 12 Greek hospitals and the majority of them (80%) belonged to serotype 0:12. The isolates were distributed to a variety of different antibiotic resistance phenotypes. Plasmid analysis showed that 10 isolates harboured plasmids ranging in size from 20 to 100 Mda. Among these strains, four carried plasmids of 100 Mda, two strains had 60 Mda plasmid each while in three strains the plasmids detected were 65, 25 and 20 Mda, respectively. One strain harboured two plasmids of 100 and 60 Mda. All strains containing plasmids belonged to 0:12 serotype, except the one harbouring the 25 Mda plasmid, which belonged to serotype 0:6. Using a P. aeruginosa recipient resistant to rifampicin and ciprofloxacin, conjugal transfer was achieved in two occasions. These plasmids, 100 Mda in size, encoded high-level resistance to both gentamicin and tobramycin whereas resistance to other drugs was not transferable. Interestingly, all 100 Mda plasmids, including the self-transferable ones, were found to share a certain degree of homology as judged by restriction analysis. It is suggested that both resistance phenotypes and analysis of plasmid content might be useful in subdividing 0:12 multi-resistant P. aeruginosa.

Pseudomonas aeruginosa clinical isolates: Serotypes, resistance phenotypes and plasmid profiles

“…The other values too are higher than those obtained by Plesiat et al [21] and by Tsakris et al [6]; they, however, also found bigger plasmids using different techniques.…”

“…Pitt et al [20] and Tsakris et al [6] isolated a high percentage of 0:12 serotype multiresistant strains in Europe.…”

“…Therefore it is frequently isolated as opportunistic pathogen in recurrent infections of hospitalized patients [2,3], being the major Cause of morbidity and mortality in patients with compromised immunity, including those with cystic fibrosis (CF), neutropenia, extended burns and AIDS [4][5][6].…”

Antimicrobial activity of commonly used antibiotics and DNA fingerprint analysis of Pseudomonas aeruginosa obtained from clinical isolates and unchlorinated drinking water in Korea, 2010

“…In fact, the rate of development of resistance of P. aeruginosa to new antibiotics is much faster than the rate of development of new antibiotics (Tsakris et al, 1992;Holder et al,, 1995;Bukowska et al, 1996).…”

Patterns of antibiotics susceptibility of isolates and plasmid analysis of Staphylococcus from surgical site infections in Nigeria

“…Acquisition of mobile genetic elements is known to be the main mechanism for short term accumulation of resistance determinants in bacterial genomes (Yah et al, 2007a). Other studies have shown resistance to gentamicin, tobramycin and carbenicillin to be attributed to transferable plasmids (Tsakris et al, 1992). Glatman et al (2001) in Greece, found plasmids (100Mda in size) isolated from multidrug resistant Pseudomonas aeruginosa strains, which encode high-level resistance to gentamicin and tobramycin; whereas resistant to other drugs such as ciprofloxacin and rifampicin were not transferable and all.…”