Revista de biología marina y oceanografía

Bio-Corrosion, Sulfate-Reducing Bacteria in the Yucatan Peninsula

Ma Leticia Arena-Ortiz, Muhilan Mahendhiran, Mariela ReyesSosa and Joanna Ortiz-Alcantara

Microorganisms colonize the engineering materials and could damage them eventually. Sulfate reducing bacteria (SRB, hereafter) are responsible for corrosion in various metals such as carbon steel, stainless steel, iron and some alloys. Biocorrosion causes huge loss every year which causes various socio and economic complications. In anaerobic environments, SRB are active and thus microbiologically influenced corrosion (MIC) could occur. However, molecular mechanisms of MIC are less understood. Therefore, it is important to recognize the microorganisms at the molecular level and their mechanisms associated to biocorrosion, in order to reduce/prevent damages caused by these organisms. Also, the identification of various genera and species related to biocorrosion is needed. In this article, we determined the presence of SRB related to biocorrosion under anoxic conditions in the Yucatan Peninsula of Mexico. Water and sediment samples were collected from a total of twenty-one sampling sites coming under four environmental types (Freshwater upwelling’s, Lagoon, Sea, Sea (Beach) and Wetlands) in Sisal Coastal region of Yucatan State in Mexico. Physicochemical parameters such as pH, salinity, dissolved oxygen, conductivity; total dissolved solids, redox potential and temperature were monitored in situ. 16S ribosomal RNA (rRNA) gene-based sequencing analysis showed that, out of 37 bacterial genera in SRB group, mainly eight anaerobic bacteria were present in both water and sediment samples including Desulfatibacillum, Desulfatitalea, Desulfobacula, Desulfobulbus, Desulfotignum, Desulfotomaculum, Desulfovibrio and Sulfurospirillum. Principal Component Analysis (PCA) showed that at least six variables were correlated between the selected sampling sites. Hierarchical Cluster Analysis (HCA) indicated a minimum of five groups of environmental variables, including outgroup and two major clusters. This is the first study of the presence of sulfate reducing bacteria which could cause biocorrosion in the Yucatan Peninsula of Mexico.