Characterization of Tree Benzoate Degrading Anoxygenic Photosynthetic Bacteria Isolated from the Envionment

Abstract

Three anoxygenic photosynthetic bacteria, DS-I, DS-4 and Cas-13, have been examinated for their morphological and physiological properties. All strains were rod-shape cells with a swollen terminal end, Gram negative, motile, non-halophilic, non-alkalophilic and non-acidophilic, and capable of utilizing benzoate aerobically and photo-anaerobically. Sequence analysis of part of 16s rRNA genes showed that DS-1 and Cas-13 were closely elated to RhodopseudomonaspalusfrisS train 7 with asimilarity of97%, whereas DS-4 may not be closely related to the former two strains with a similarity of 78% based on the constructed phylogenic tree. Spectral analysis indicated that the three bacteria had bacteriochlorophyl a and normal spirilloxanthin series. Growth in medium enriched with vitamin and supplemented with benzoate as their sole C-sources was better than in medium without vitamin. Benzoate degradation in medium with vitamin was accelerated. The ability to grow on benzoate without added vitamins indicated that the bacteria were able to synthesize their own vitamins.