Identification of manganese oxidizing bacteria isolated from biological filtration water plants

PIAZZA A; PACINI V; SANGUINETTI G; INGALLINELLA AM; OTTADO J; GOTTIG N

Rosario

Congreso; L Reunión Anual de la Sociedad Argentina de Investigación Bioquímica y Biología Molecular.; 2014

SAIB

Despite the prevalence of Mn oxidizing microbes and their important role in biogeochemical cycling, the physiological function of bacterial Mn(II) oxidation remains enigmatic. Therefore, the specific objectives of this study were to isolate and identify Mn-oxidizing bacteria; and study, in a future, the physiological function of the bacterial Mn oxidation process. Samples were collected from biofiltration systems that remove the Mn present in underground waters by the biological oxidation of this metal. The samples were dissolved in PBS and different physicochemical parameters were measured. Then they were plated on different solid selective media (Mn-medium, PC-medium and Lept-medium) designed to isolate different species of Mn oxidizers. Mn-oxidizing bacteria were identified through color changes of colonies. In the absence of Mn, the colonies on the agar were whitish while in Mn containing medium they shifted to brownish, due to Mn oxides. 150 putative Mn-oxidizing strains were obtained and subsequently identified by microscopic observations and Gram-staining. Also, amplification by PCR of specific regions of the 16S RNAs allowed the molecular identification of the strains by phylogenetic analysis. Futures studies using these isolates will contribute to the understanding of the physiological role of bacterial Mn(II) oxidation.