Biochemical and molecular characterization of bacteria in reverse osmosis membrane

Abstract

Bacterial characterization and study of genes related to the coding of proteins responsible of biofouling, as well as an assessment of the production of exopolymeric substances in bacteria isolated from a reverse osmosis membrane. Six bacteria were isolated with biochemical tests and DNA was extracted for subsequent amplify with the selected primers alpP and spoOA, the primers described are related to the coding of fouling proteins and to the coding of proteins in antifouling events. In addition, the adhesive matter to the membrane was analyzed with these primers in the same way. Biochemical tests revealed the genus and species of 4 of the 6 bacteria, including the presence of Sphingomonas paucimobilis, Vibrio metschnikovii and Aeromonas salmonicida ssp salmonicida. Sphingomonas spp. is a very common genus and documented in studies related to fouling in reverse osmosis membranes, whereas the species of Vibrio metschnikovii and Aeromonas salmonicida are usually found causing fish pathologies. It is not possible to characterize all isolated bacteria, the standard biochemical tests they usually use are not intended to characterize environmental bacteria. Amplification was obtained in all bacteria with the selected primers, but it was not obtained a clearly amplification with the environmental samples. Among the isolated bacteria Sphingomonas paucimobilis outstanding for the production of EPS.