Aims: The investigation aimed to examine the crude oil-contaminated soil Streptomyces flora and study their capability to grow on diesel fuel as a sole carbon source and their analysis for the presence of alkane hydroxylase gene (alkB) by PCR. Methodology and results: A total of 17 Streptomyces isolates were recovered from hydrocarbon-contaminated soil samples on starch casein nitrate agar medium with the ability of 4 isolates to grow on diesel [0.1 % (v/v)] as assessed by agar plate diffusion method, enzymatic assay and dry weight measurements. The ability of the four isolates (JR2b, JR3a, JR5b, and JR6f) to grow on diesel was revealed by the colour change of the reaction mixture and showing a growth response by growing around diesel-containing wells with a percentage increase in the dry weight of 24.60, 26.23, 18.03, and 18.03 after 28 days of incubation as compared to zero time, respectively. Although the four isolates were capable to degrade diesel as indicated by the three assessment techniques, they did not show any PCR product. Conclusion, significance and impact of study The isolates that grew on diesel and showed no PCR product might not contain the alkB gene, which implies that alkB gene is not the only gene that is responsible for the degradation of alkanes.

Aims: Staphylococcus aureus is a Gram positive pathogen distributed worldwide and represents a rising problem for both hospitals and community. The aims of the study were to examine the antibiograms, toxin profiles as well as the genetic diversity of a set of S. aureus isolates from clinical and food samples. Methodology and results: To get some insights on the genetic heterogeneity and test for the presence of certain virulence genes, all isolates were subjected to different PCR amplifications and antibiotic sensitivity analysis. The mecA gene was detected in both clinical and food isolates. Resistance to penicillin and amoxicillin was observed in both clinical and food isolates. About 88% of both food and clinical isolates harbored the toxin gene sea, while 70% and 29% of clinical and food isolates respectively, harbored sec. The seb gene was detected in 59% and 18% of clinical and food isolates, respectively. Dendrograms prepared from the VNTR, antibiograms and toxin profiles, revealed 89, 52 and 12 clusters, respectively. Thus, suggesting a very high heterogeneity among the isolates. Conclusion, significance and impact of study: Strains used in this study showed high heterogeneity when examined by VNTR or antibiograms, while appeared less heterogeneous when dendrogram was generated based on toxin profiles. This study highlights the fact that methicillin resistance in S. aureus might be generated within the health institutions or the community. Obtained results also might help health authorities understand the origin of methicillin resistant clones within the study area.
Staphylococcus ; Drug Resistance, Microbial