RESUMEN
Pollution from petroleum products is of public health concern because of its attendant health and environmental impacts. Aims: To study the biodegradation of Bonny light crude petroleum by bacteria isolated from soils of three different automobile mechanic workshops in Ota, Ogun State. Study Design: Contaminated soils from three (3) different auto-mechanic sources were enriched with Bonny light crude oil for a period of twenty-one (21) days after which the culture was changed and further enriched using crude oil as the only source of carbon and energy. Place and Duration of Study: Department of Biological Sciences (Microbiology Unit), Covenant University, Ota, Ogun State Nigeria, between June 2016 and March 2017. Methodology: Bacteria were isolated using standard microbiological techniques from enrichment of the soil samples in minimal salt medium (MSM) supplemented with 1% (v/v) crude petroleum as the only source of carbon and energy. The petroleum utilizing bacteria belonging to the genera Bacillus sp. (SB4), Pseudomonas sp. (SC8), Serratia sp. (SC11), and Acinetobacter sp. (SC12) were screened and subjected to oil degradation procedures. Gas Chromatographic (GC) analysis was used to analyze the component and percentage of the petroleum utilized. Plasmid curing and profiling were performed to determine whether the ability to utilize carbon is plasmid or chromosomally encoded. Results: Four (4) bacterial strains out of thirty-six (36) bacterial isolates were able to utilize petroleum as energy source. The GC fingerprints showed that both the aliphatic and aromatic components of crude petroleum were reduced to varying degree with the exception of nonadecane C19. Strain SC11 could not reduce anthracene, chrysene, benzo(a)pyrene and pyrene components of the crude petroleum. Strain SB4 depleted 24% - 57% of the aliphatic and 20% - 42% of the aromatics components while strain SC8 depleted 38% - 67% of the aliphatic and 30% - 79% of the aromatics components. However, strain SC11 only depleted 12% - 46% of the aliphatic and 13% - 29% of the aromatics components of the crude petroleum used. Conclusion: All organisms harbored plasmid which suggests that petroleum degradation capabilities could be plasmid encoded. This indicates that the petroleum utilizing bacteria which are part of the ecosystem could be used for natural remediation of petroleum polluted environments.
RESUMEN
ABSTRACT Studies were conducted to characterize Klebsiella pneumoniae isolates from urinary tract infection (UTI) patients in Sylhet city of Bangladesh. At the same time, all isolates were screened for some common virulence genes and four significant isolates were searched for plasmid number and sizes by mini alkaline-lysis method. Among five tested isolates from female UTI patients, gyrase subunit B2 (gyrb2) amplified in all isolates, lipase and nuclease detected in three isolates and serine protease amplifies in two isolates and gave the expected band of 1130 bp, 517 bp, 1055 bp and 211 bp respectively. Two of four isolates showed 9.82 kb plasmid band on agarose gel. Isolates bearing 9.82 kb plasmid were found to be resistant to multiple commercial antibiotics. At the same time all isolates were screened for in-vitro plate assay for proteolytic, lypolytic and hemolytic activity. Isolates with positive plasmid and more than one virulent gene with gyrB2 showed positive result in in-vitro culture plate with clear zone of proteolysis, hemolysis or lipolysis. This study will be helpful for further study in finding correlation or pattern of virulence properties for K. pneumoniae associated UTI in Bangladesh.
RESUMEN
Antibiograms and plasmid profiles are commonly used to characterizemethicillin-resistant Staphylococcus aureus (MRSA) inepidemiologic studies. However, antibiograms are frequently inadequate to accomplish the differentiation. Plasmid profile being more informative has been reported to be useful in tracing the epidemiology of antibiotic resistance. Antibiotic resistance patterns and plasmid profiles of methicillin-resistant Staphylococcus aureus (MRSA) isolates from human specimens were investigated to determine the discriminatory power of plasmid profile analysis in conjunction with antibiotic susceptibility pattern. Specimens were analyzed using disc diffusion assay and restriction enzymes analysis of plasmid DNA procedure. The 51 methicillin-resistant Staphylococcus aureus (MRSA) isolates were grouped into 18 groups using their resistogram. Twenty four (47.1%) strains out the 51 methicillin-resistant Staphylococcus aureus (MRSA) isolates harbored plasmids. Single plasmid isolates were 14(27.5%), double plasmid isolates were 6(11.8%) while tripple plasmid isolates were 4(7.8%). The 24 isolates containing plasmids were categorized into 14 groups based on their resistogram. Plasmid profile showed greater similarity between isolates (10 profiles) than antibiotic resistance pattern which showed a higher disparity (14 patterns). However, resistance to various antimicrobial agents was not consistent with the presence of plasmids. No particular molecular size plasmid could be associated with any particular antimicrobial resistance patterns. Resistance was observed in isolates with various molecular size plasmids as well as in those that had no plasmids. Nonetheless, 2 pairs of isolates with the same plasmid profile also had similar (almost the same) resistance pattern. Plasmid profile analysis in conjunction with the antibiotic resistance typing is valuable in the epidemiological investigation of methicillin-resistant Staphylococcus aureus (MRSA).