Characterization of an IncFII Plasmid Encoding NDM-1 from Escherichia coli ST131

Background: The current spread of the gene encoding the metallo-ß-lactamase NDM-1 in Enterobacteriaceae is linked to a variety of surrounding genetic structures and plasmid scaffolds. Methodology: The whole sequence of plasmid pGUE-NDM carrying the bla NDM-1 gene was determined by high-density pyrosequencing and a genomic comparative analysis with other blaNDM-1-negative IncFII was performed. Principal Findings: Plasmid pGUE-NDM replicating in Escherichia coli confers resistance to many antibiotic molecules including b-lactams, aminoglycosides, trimethoprim, and sulfonamides. It is 87,022 bp in-size and carries the two b-lactamase genes bla NDM-1 and bla OXA-1, together with three aminoglycoside resistance genes aacA4, aadA2, and aacC2. Comparative analysis of the multidrug resistance locus contained a module encompassing the blaNDM-1 gene that is actually conserved among different structures identified in other enterobacterial isolates. This module was constituted by the blaNDM-1 gene, a fragment of insertion sequence ISAba125 and a bleomycin resistance encoding gene. Significance: This is the first characterized bla NDM-1-carrying IncFII-type plasmid. Such association between the bla NDM-1 gene and an IncFII-type plasmid backbone is extremely worrisome considering that this plasmid type is known to sprea

Post-translational regulation of the RpoS and PsrA genes in pseudomonas putida WCS358: The role of ClpXP protease

RpoS i PsrA proteini su ključni transkripcioni regulatori koji se kod pseudomonada aktiviraju u odgovoru na stacionarnu fazu rasta. Cilj ove studije bio je utvrđivanje uloge ClpXP (ATP zavisna serin proteaza) u stabilnosti RpoS i PsrA proteina tokom različitih faza rasta u Pseudomonas putida WCS358. "Western blot" analiza proteinskih ekstrakata P. putida WCS358 i P. putida WCS358 clpX::Km iz rane eksponencijalne, Kasne eksponencijalne i stacionarne faze rasta, sa antitelima na RpoS i PsrA, pokazala je da ClpXP degraduje RpoS i PsrA u ranoj eksponencijalnoj fazi rasta.The RpoS and PsrA proteins are key transcriptional regulators that are activated in response to the stationary phase of growth in pseudomonads. This study was designed to establish whether ClpXP (ATP-dependent serine protease) regulates levels of RpoS and PsrA in Pseudomonas putida WCS358. Western blot analysis of P. putida WCS358 protein extracts from the early exponentianl, late exponential, and stationary phases of growth with antibodies against RpoS and PsrA revealed that these proteins are degraded by ClpXP in the early exponential phase of growth. The obtained results demonstrate a role for ClpXP protease in post-translational regulation of proteins encoded by the rpoS and psrA genes in Pseudomonas spp

Dynamics of sodium dodecyl sulfate utilization andantibiotic susceptibility of strain Pseudomonas sp. ATCC19151

Poznato je da soj Pseudomonas sp. ATCC19151 poseduje gen koji kodira Potencijalnu alkilsulfatazu. U ovom radu analizirana je sposobnost rasta ovog soja u minimalnom medijum usa različitim koncentracijama natrijum dodecilsulfata (0.5, 0.75 i 1 %) kao jedinim izvorom ugljenika. Pokazano je da Pseudomonas sp. ATCC19151 ispoljava najbolji rast uminimalnom medijumusa 0.5 % natrijum dodecil sulfata, te je stoga ova koncentracija uzeta kao optimalna za testiranje dinamike korišćenja natrijum dodecil sulfata tokom različitih faza rasta. Dinamika korišćenja natrijum dodecil sulfata podudarala se sa rastom kulture. Pored toga u cilju detaljnije karakterizacije soja, analizirana je i osetljivost Pseudomonas sp. ATCC19151 na antibiotike. Pokazano je da je analizirani soj rezistentan na šest (ampicilin, tetraciklin, hloramfenikol, tobramicin, nalidiksičnukiselinui gentamicin) od devet analiziranih antibiotika.Pseudomonas sp. ATCC19151 harbors a gene encoding a putative alkylsulfatase (sdsA). Here we report a growth ability of this strain in minimal media containing 0.5, 0.75, and 1% sodium dodecyl sulfate as the sole carbon source. The most prominent growth was detected for the minimal medium with 0.5% SDS, so this concentration of SDS was used to monitor Pseudomonas sp. ATCC19151 SDS biodegradation dynamics. Bacterial growth coincided with the disappearance of SDS. Antibiotic susceptibility was tested as well. Pseudomonas sp. ATCC19151 was resistant to six out of nine tested antibiotics, including ampicillin, tetracycline, chloramphenicol, tobramycin, nalidixic acid, and gentamycin