Pseudomonas sp. a Dominant Population of Bacteria in the Cold Water of Mount Sabalan Crater ‎Lake

Abstract

Sabalan (Savalan) Lake is a stable crater lake locating at the summit of Sabalan, an inactive stratovolcano and the third highest mountain of Iran. Because of cold weather conditions, the lake is frozen in most months of the year. The biodiversity of microbial flora in this area needs to be explored to find its similarity with the arctic regions’ biodiversity. The psychrophilic bacterial population of Sabalan (Savalan) Crater Lake was identified. The current research is the first report of aquatic bacterial strains isolation and characterization from Sabalan Lake. Water sample collections were cultured on four different media, then colonies were isolated by the plating method. The phylogenetic features of the isolates were scrutinized and finally, the phenotypic characteristics were investigated using specific culture methods. The results of morphological tests indicated that most isolates were Gram-negative and rod shape, which were able to grow between ˗4 and +37 ºC.‎ According to the phylogenetic analysis the isolated strains belong to Pseudomonas, Yersinia, Kocuria, and Micrococcus genera and about 60% of the isolates belong to the various species of Pseudomonas as a ‎dominant genus with abounded frequency. ‎In addition, several isolates showed 99% similarity with bacteria, which were previously isolated from Antarctic regions such as Pseudomonas antarctica and Micrococcus antarctica. It can be concluded that the microbial populations of cold areas is the same across the geographical distances. In addition, these bacterial strains could be a primitive source of new enzymes for technological applications such as biosurfactant production.