title: Multidrug resistance in hydrocarbon-tolerant Gram-positive and Gram-negative bacteria.
abstract: New Gram-positive and Gram-negative bacteria were isolated from Poeni oily sludge, using enrichment procedures. The six Gram-positive strains belong to Bacillus, Lysinibacillus and Rhodococcus genera. The eight Gram-negative strains belong to Shewanella, Aeromonas, Pseudomonas and Klebsiella genera. Isolated bacterial strains were tolerant to saturated (i.e., n-hexane, n-heptane, n-decane, n-pentadecane, n-hexadecane, cyclohexane), monoaromatic (i.e., benzene, toluene, styrene, xylene isomers, ethylbenzene, propylbenzene) and polyaromatic (i.e., naphthalene, 2-methylnaphthalene, fluorene) hydrocarbons, and also resistant to different antimicrobial agents (i.e., ampicillin, kanamycin, rhodamine 6G, crystal violet, malachite green, sodium dodecyl sulfate). The presence of hydrophilic antibiotics like ampicillin or kanamycin in liquid LB-Mg medium has no effects on Gram-positive and Gram-negative bacteria resistance to toxic compounds. The results indicated that Gram-negative bacteria are less sensitive to toxic compounds than Gram-positive bacteria, except one bacteria belonging to Lysinibacillus genus. There were observed cellular and molecular modifications induced by ampicillin or kanamycin to isolated bacterial strains. Gram-negative bacteria possessed between two and four catabolic genes (alkB, alkM, alkB/alkB1, todC1, xylM, PAH dioxygenase, catechol 2,3-dioxygenase), compared with Gram-positive bacteria (except one bacteria belonging to Bacillus genus) which possessed one catabolic gene (alkB/alkB1). Transporter genes (HAE1, acrAB) were detected only in Gram-negative bacteria.
authors.affiliation: Institute of Biology, Center of Microbiology, 296 Spl. Independentei St, Bucharest, Romania. mihaela.stancu@ibiol.ro
authors.forename: Mihaela Marilena
authors.initials: MM
authors.lastname: Stancu
authors.forename: Magdalena
authors.initials: M
authors.lastname: Grifoll
mesh_terms: D000473:Alkanes / Q000494:pharmacology; D000667:Ampicillin / Q000494:pharmacology; D000890:Anti-Infective Agents / Q000494:pharmacology*; D001692:Biological Transport / Q000235:genetics; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D006094:Gram-Positive Bacteria / Q000187:drug effects* / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D006838:Hydrocarbons / Q000494:pharmacology*; D006841:Hydrocarbons, Aromatic / Q000494:pharmacology; D007612:Kanamycin / Q000494:pharmacology; D050356:Lipid Metabolism / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D006899:Mixed Function Oxygenases / Q000235:genetics; D016133:Polymerase Chain Reaction; D011506:Proteins / Q000187:drug effects / Q000378:metabolism; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012722:Sewage / Q000382:microbiology; D001616:beta-Galactosidase / Q000187:drug effects / Q000378:metabolism
chemical_list: D000473:Alkanes; D000890:Anti-Infective Agents; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D006838:Hydrocarbons; D006841:Hydrocarbons, Aromatic; D011506:Proteins; D012336:RNA, Ribosomal, 16S; D012722:Sewage; D007612:Kanamycin; D000667:Ampicillin; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; D001616:beta-Galactosidase