Bacterial diversity and the antimicrobial resistome in the southwestern highlands of Saudi Arabia.

Soil is a reservoir of microbial diversity and the most supportive habitat for acquiring and transmitting antimicrobial resistance. Resistance transfer usually occurs from animal to soil and vice versa, and it may ultimately appear in clinical pathogens. In this study, the southwestern highlands of Saudi Arabia were studied to assess the bacterial diversity and antimicrobial resistance that could be affected by the continuous development of tourism in the region. Such effects could have a long-lasting impact on the local environment and community. Culture-dependent, quantitative polymerase chain reaction (qPCR), and shotgun sequencing-based metagenomic approaches were used to evaluate the diversity, functional capabilities, and antimicrobial resistance of bacteria isolated from collected soil samples. Bacterial communities in the southwestern highlands were mainly composed of Proteobacteria, Bacteroidetes, and Actinobacteria. A total of 102 antimicrobial resistance genes (ARGs) and variants were identified in the soil microbiota and were mainly associated with multidrug resistance, followed by macrolide, tetracycline, glycopeptide, bacitracin, and beta-lactam antibiotic resistance. The mechanisms of resistance included efflux, antibiotic target alteration, and antibiotic inactivation. qPCR confirmed the detection of 18 clinically important ARGs. In addition, half of the 49 identified isolates were phenotypically resistant to at least one of the 15 antibiotics tested. Overall, ARGs and indicator genes of anthropogenic activities (human-mitochondrial [hmt] gene and integron-integrase [int1]) were found in relatively lower abundance. Along with a high diversity of bacterial communities, variation was observed in the relative abundance of bacterial taxa among sampling sites in the southwestern highlands of Saudi Arabia.

Taxonomic diversity of antimicrobial-resistant bacteria and genes in the Red Sea coast.

Despite development of a record number of recreational sites and industrial zones on the Red Sea coast in the last decade, antibiotic-resistant bacteria in this environment remain largely unexplored. In this study, 16S rDNA sequencing was used to identify bacteria isolated from 12 sediment samples collected from the Red Sea coastal, offshore, and mangroves sites. Quantitative PCR was used to estimate the quantity of antimicrobial resistance genes (ARGs) in genomic DNA in the samples. A total of 470 bacteria were isolated and classified into 137 distinct species, including 10 candidate novel species. Site-specific bacterial communities inhabiting the Red Sea were apparent. Relatively, more resistant isolates were recovered from the coast, and samples from offshore locations contained the most multidrug-resistant bacteria. Eighteen ARGs were detected in this study encoding resistance to aminoglycoside, beta-lactam, sulfonamide, macrolide, quinolone, and tetracycline antibiotics. The qnrS, aacC2, ermC, and blaTEM-1 genes were commonly found in coastal and offshore sites. Relatively higher abundance of ARGs, including aacC2 and aacC3, were found in the apparently anthropogenically contaminated (beach) samples from coast compared to other collected samples. In conclusion, a relative increase in antimicrobial-resistant isolates was found in sediment samples from the Red Sea, compared to other studies. Anthropogenic activities likely contribute to this increase in bacterial diversity and ARGs.

Impact of mass migrations on the clonal variation of clinical Staphylococcus aureus strains isolated from the Western region of Saudi Arabia.

OBJECTIVES: A rapid molecular typing system was used to determine the impact of mass migration on the clonal variation of Staphylococcus aureus isolates recovered from King Abdulaziz University Hospital (KAUH) Jeddah, in the western region of Saudi Arabia. This region experiences an annual influx of millions of pilgrims. METHODS: SmaI-multiplex PCR typing (SMT) was used for the initial analysis of strains and the resulting data subsequently supported by Multi-Locus Sequence Typing (MLST). RESULTS: A total of 89 S. aureus isolates were SMT typed and revealed a high degree of genetic variation, with 40 SMT profiles detected among the isolates. Representatives of all forty SMT types were subsequently analysed by MLST, identifying 26 sequence types. A novel sequence type (ST), named ST3303, was identified in two methicillin-sensitive S. aureus (MSSA) isolates. MSSA strains exhibited more diversity than methicillin-resistant S. aureus (MRSA) strains, with community acquired MSSA and MRSA strains reaching alarmingly high levels. CONCLUSION: The relatively high degree of genetic diversity found among S. aureus isolates of single hospital was attributed to the fact that Jeddah is the principal gateway to Mecca, visited each year by millions of pilgrims from many countries. The observed diversity clearly reflects the impact of such mass migrations in the rapid dissemination of strains world-wide. Our findings suggest the importance of surveillance programmes in locations affected by mass migrations, both to monitor their impact on endemic strains and for the detection of pandemic strains. SMT provides a cost-effective and sensitive typing method for achieving this objective.

Non contiguous-finished genome sequence and description of Bacillus jeddahensis sp. nov.

Strain JCE(T) was isolated from the fecal sample of a 24-year-old obese man living in Jeddah, Saudi Arabia. It is an aerobic, Gram-positive, rod-shaped bacterium. This strain exhibits a 16S rRNA nucleotide sequence similarity of 97.5 % with Bacillus niacini, the phylogenetically closest species with standing nomenclature. Moreover, the strain JCE(T) presents many phenotypic differences, when it is compared to other Bacillus species, and shows a low MALDI-TOF Mass Spectrometry score that does not allow any identification. Thus, it is likely that this strain represents a new species. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 4,762,944 bp long genome (1 chromosome but no plasmid) contains 4,654 protein-coding and 98 RNAs genes, including 92 tRNA genes. The strain JCE(T) differs from most of the other closely Bacillus species by more than 1 % in G + C content. In addition, digital DNA-DNA hybridization values for the genome of the strain JCE(T) against the closest Bacillus genomes range between 19.5 to 28.1, that confirming again its new species status. On the basis of these polyphasic data made of phenotypic and genomic analyses, we propose the creation of Bacillus jeddahensis sp. nov. that contains the strain JCE(T).

Ameliorating effect of olive oil on fertility of male rats fed on genetically modified soya bean.

BACKGROUND: Genetically modified soya bean (GMSB) is a commercialized food. It has been shown to have adverse effects on fertility in animal trials. Extra virgin olive oil (EVOO) has many beneficial effects including anti-oxidant properties. The aim of this study is to elucidate if addition of EVOO ameliorates the adverse effects on reproductive organs of rats fed on GMSB containing diet. METHODS: Forty adult male albino rats (150-180 g) of Sprague Dawley strain were separated into four groups of 10 rats each: Group 1 - control group fed on basal ration, Group 2 - fed on basal ration mixed with EVOO (30%), Group 3 - fed on basal ration mixed with GMSB (15%), and Group 4 - fed on basal ration mixed with GMSB (15%) and EVOO (30%). This feeding regimen was administered for 65 days. Blood samples were collected to analyze serum zinc, vitamin E, and testosterone levels. Histopathological and weight changes in sex organs were evaluated. RESULTS: GMSB diet reduced weight of testis (0.66±0.06 vs. 1.7±0.06, p<0.001), epididymis (0.489±0.03 vs. 0.7±0.03, p<0.001), prostate (0.04±0.009 vs. 0.68±0.04, p<0.001), and seminal vesicles (0.057±0.01 vs. 0.8±0.04, p<0.001). GMSB diet adversely affected sperm count (406±7.1 vs. 610±7.8, p<0.001), motility (p<0.001), and abnormality (p<0.001). GMSB diet also reduced serum zinc (p<0.05), vitamin E (p<0.05), and testosterone (p<0.05) concentrations. EVOO diet had no detrimental effect. Addition of EVOO to GMSB diet increased the serum zinc (p<0.05), vitamin E (p<0.05), and testosterone (p<0.05) levels and also restored the weights of testis (1.35±0.16 vs. 0.66±0.06, p<0.01), epididymis (0.614±0.13 vs. 0.489±0.03, p<0.001), prostate (0.291±0.09 vs. 0.04±0.009, p<0.001), seminal vesicle (0.516±0.18 vs. 0.057±0.01, p<0.001) along with sperm count (516±3.1 vs. 406±7.1, p<0.01), motility (p<0.01), and abnormality (p<0.05). CONCLUSION: EVOO ameliorates the adverse effects of GMSB on reproductive organs in adult male albino rats. This protective action of EVOO justifies its use against the oxidative damage induced by GMSB in reproductive organs.

Composition of soil microbiome along elevation gradients in southwestern highlands of Saudi Arabia.

BACKGROUND: Saudi Arabia is mostly barren except the southwestern highlands that are susceptible to environmental changes, a hotspot for biodiversity, but poorly studied for microbial diversity and composition. In this study, 454-pyrosequencing of 16S rRNA gene hypervariable region V6 was used to analyze soil bacterial community along elevation gradients of the southwestern highlands. RESULTS: In general, lower percentage of total soil organic matter (SOM) and nitrogen were detected in the analyzed soil samples. Total 33 different phyla were identified across the samples, including dominant phyla Proteobacteria, Actinobacteria and Acidobacteria. Representative OTUs were grouped into 329 and 508 different taxa at family and genus level taxonomic classification, respectively. The identified OTUs unique to each sample were very low irrespective of the altitude. Jackknifed principal coordinates analysis (PCoA) revealed, overall differences in the bacterial community were more related to the quantity of specific OTUs than to their diversity among the studied samples. CONCLUSIONS: Bacterial diversity and soil physicochemical properties did not show consistent changes along the elevation gradients. The large number of OTUs shared between the studied samples suggest the presence of a core soil bacterial community in the southwestern highlands of Saudi Arabia.

Paper money and coins as potential vectors of transmissible disease.

Paper currency and coins may be a public health risk when associated with the simultaneous handling of food and could lead to the spread of nosocomial infections. Banknotes recovered from hospitals may be highly contaminated by Staphylococcus aureus. Salmonella species, Escherichia coli and S. aureus are commonly isolated from banknotes from food outlets. Laboratory simulations revealed that methicillin-resistant S. aureus can easily survive on coins, whereas E. coli, Salmonella species and viruses, including human influenza virus, Norovirus, Rhinovirus, hepatitis A virus, and Rotavirus, can be transmitted through hand contact. Large-scale, 16S rRNA, metagenomic studies and culturomics have the capacity to dramatically expand the known diversity of bacteria and viruses on money and fomites. This review summarizes the latest research on the potential of paper currency and coins to serve as sources of pathogenic agents.

Nucleic acid amplification technology for hepatitis B virus, and its role in blood donation screening in blood banks.

OBJECTIVE: To investigate the performance of hepatitis B virus polymerase chain reaction (HBV PCR) using one of the commercial methods used around the world to screen for HBV in some blood donors where other conventional serological assays have limitations to detect the virus. METHODS: This study was designed to use Amplicor AmpliScreen for HBV testing to detect the presence of the HBV DNA in the specimens tested by COBAS AmpliPrep system using a modified manufacture protocol COBAS AmpliPrep of total nucleic acid isolation (TNAI) kit. All serological tests were carried out on the donors' samples to detect the hepatitis B surface antigen (HBsAg), Australian antibody anti-HBs (AUSAB) and hepatitis B core antigen (HBcAg) in the 2 periods of the study. The first period was started in February 2005 and the second period was started in April 2007. Both periods were continued for 2 months after beginning in the molecular pathology laboratory, Al-Hada Armed Forces Hospital, Taif, Kingdom of Saudi Arabia. The 600 donors' data were then studied and analyzed. RESULTS: Five nucleic acid amplification test (NAT-HBV) positives were found out of 600. There were 3 positive for HBcAb and negative for HBsAg, 2 had reading with <100 mIU/mL anti-HBs (AUSAB), and one had >100 mIU/mL AUSAB readings. CONCLUSION: Our results show that there is a possibility to have occult HBV infection in some donors that cannot be detected by the HBsAg routine serological assays. Moreover, the study can be useful to formulate a new deferral policy based on the implementation of NAT-HBV for blood screening.