Isolation of haloalkaliphilic microorganisms from leather industry

Abstract

Haloalkalophiles are extremophilic microorganisms that are adapted to saline and alkaline conditions. Different species of them have been isolated so far from soda lakes and soil samples. Haloalkalophilic microorganisms have significant adaptive mechanisms to avoid denaturing effect of salts and to balance their interior pH. Extracellular enzymes that are produced by these halophilic and alkalophilic microorganism are applicable for industrial purposes. Therefore isolation of these organisms from their habitats and study on genotypic characterization constitute initial steps for furter biotechnological studies. In this study, processing steps of leather factories and their wastewater were chosen for sampling. In order to isolate target microorganisms Horikoshi-I medium including 12% NaCl was used. After isolation microorganisms were purified. Phenotypic tests were applied (Gram staining, catalase and oxidase behaviors, spore observation by phase contrast microscope, sensitivity to antibiotics and extracellular enzyme screenings). For genotypic characterization, genomic DNA was isolated and 16S-ITS rDNA region was amplified. Differentiation was achieved according to Restriction Fragment Length Polymorphism (RFLP) method by using Hae III and Taq I endonucleases. Isolates, which represented the different RFLP patterns, were chosen for building up the haplotype groups. As a result of the study seven different RFLP haplotypes were identified.Moreover, 16S ribosomal DNA partial sequencing was also performed on some of the strains in. These haloalkalophilic microorganisms and their enzymes could be used in different biotechnological studies in the future for various industrial applications.