Compilation of Analytical Techniques for Discrimination of Halophilic Archaea and Bacteria

Since discovery, the halophilic archaeal and bacterial strains were studied for their unique compounds such as pigments, proton pumps, compatible solutes and enzymes. Due to their tolerance to extreme salinities several research on using these organisms in various fields is conducted worldwide. Though sequencing is an efficient way of identifying an organism, the difficulty of selecting an optimal archaea primer for identification of archaea is tedious. Therefore, it is essential to discriminate them as bacteria or archaea before going for sequencing studies. There are several conventional and analytical techniques followed in discriminating and identifying the halophilic archaea and bacteria. The present study is an investigation of various conventional and analytical techniques such as morphological observations, biochemical tests, salinity optima, chloramphenicol susceptibility, growth in sodium taurocholate, lipid profiling by FAME analysis, FTIR and sequencing technique used in identifying halophilic community. This study also explains the disadvantages of each analysis and confirms the tests that can be used in the preliminary confirmation of halophilic archaea or bacteria. In the present study, halophilic archaeal and bacterial community from Solar salterns of Kelambakkam, Chennai, Tamilnadu and Tuticorin, Tamilnadu and Salt evaporation tank of tannery, Vellore, Tamilnadu were isolated and studied by various above-mentioned techniques. From the study, it was identified that FAME analysis out of other analyses can be used as preliminary method to identify and also distinguish the halophilic archaea and bacterial community.