Two of the largest crude oil-polluted areas in the world are the semi-enclosed Mediterranean and Red Seas, but the effect of chronic pollution remains incompletely understood on a large scale. We compared the influence of environmental and geographical constraints and anthropogenic forces (hydrocarbon input) on bacterial communities in eight geographically separated oil-polluted sites along the coastlines of the Mediterranean and Red Seas. The differences in community compositions and their biodegradation potential were primarily associated (P < 0.05) with both temperature and chemical diversity. Furthermore, we observed a link between temperature and chemical and biological diversity that was stronger in chronically polluted sites than in pristine ones where accidental oil spills occurred. We propose that low temperature increases bacterial richness while decreasing catabolic diversity and that chronic pollution promotes catabolic diversification. Our results further suggest that the bacterial populations in chronically polluted sites may respond more promptly in degrading petroleum after accidental oil spills.
Background: The widespread use of antiretroviral agents and the growing occurrence of HIV-1 strains resistant to these drugs have given rise to serious concerns regarding the transmission of resistant viruses to newly infected persons, which may reduce the efficacy of a first-line antiretroviral therapy. Methodology: RNA was extracted from plasma samples of 98 treatment-naïve individuals with a plasma HIV RNA viral load of at least 1,000 copies/ml. Both protease (pr) and reverse transcriptase (rt) were amplified and sequenced using an automated sequencer. National Agency for AIDS Research (ANRS) and Stanford HIV database algorithms were used for interpretation of resistance data. Results: In the protease segment, various minor mutations were present in the majority of the sequenced samples with high frequencies. Only two major mutations, M46L and V82L, were separately found in three individuals of 71 (4.2%) with one carrying both mutations. In the reverse transcriptase gene, no NNRTIs-associated resistance mutations were detected. Only one patient of 70 (1.4%) carried the F77L mutation that is associated with NRTIs resistance. Genetic subtyping revealed that 74.6% of samples were infected with subtype B, 15.5% with CRF02_AG, 4.2% with CRF01_AE, 1.4% with C, 2.8% with G and 1.4% with subtype F2. Conclusions: The low prevalence of major mutations associated with resistance to antiretroviral drugs (ARVs) among drug-naïve individuals studied suggests that the routine of drug resistance testing may be unnecessary for all Moroccan individuals newly diagnosed or all patients beginning antiretroviral therapy. Nevertheless, continuous surveillance is required since greater access to antiretroviral drugs is expected in Morocco.
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