16S_rRNA from Key West and Persian Gulf

Experiments were designed to evaluate corrosion-related consequences of storing/transporting fatty acid methyl ester (FAME) alternative diesel fuel in contact with natural seawater under anaerobic conditions. Coastal Key West, FL, and Persian Gulf seawaters, representing an oligotrophic and a more organic- and inorganic mineral-rich microbial coastal seawater environment, respectively, were used in 60-day studies with unprotected carbon steel. Despite low numbers of sulphate reducing bacteria in the original waters and after FAME diesel exposure, sulphide levels and corrosion increased markedly due to microbial sulphide production. The original microflora of the two seawaters was similar with respect to major taxonomic groups but with markedly different species. After exposure to FAME diesel the microflora of both waters changed dramatically, with Clostridiales (Firmicutes) becoming dominant. Microbial sulphide production was stimulated in both seawaters by the presence of FAME.