Isolation and identification of moderately halophilic bacteria producing hydrolytic enzymes from the largest hypersaline playa in Iran

Iran has many hypersaline environments, both the permanent and seasonal ones. One of the seasonal hypersaline lakes in the central desert zone is Aran-Bidgol Lake in which microbial diversity has not been characterized, thus the potential usage of this microbial community in biotechnology remained unknown. In this study, screening the halophilic hydrolytic enzyme-producing bacteria from different areas of this lake led to isolation of 61 gram-positive and 22 gram-negative moderately halophilic bacteria. These bacterial isolates were shown to produce a wide variety of hydrolytic enzymes including DNase, inulinase, amylase, lipase, pectinase, protease, chitinase, pullulanase, cellulase, and xylanase. The most common enzymes were DNase and inulinase in gram-positive bacteria, lipase in gram-negative bacteria, and pullulanase and cellulase in gram-positive cocci. Interestingly, combined hydrolytic activates were observed in some isolates. According to their phenotypic characteristics and comparative partial 16S rRNA sequence analysis, the moderately halophilic strains belonged to the genera Halobacillus, Thalassobacillus, Bacillus, Salinicoccus, Idiomarina, Salicola, and Halomonas.