Isolation and Identification of Halothermophilic strain of Bacillus licheniformis producing amylase from Howz Soltan Lake, Iran

This study was aimed at the isolation of halothermophilic bacteria from central desert zone (Howz Soltan salt lake) in Iran and growth property of these bacteria and their molecular phylogeny were analyzed. For this purpose, forty samples were collected from five regions as follows: vegetation part, argillaceous soils, polygon part , haloid shell and haloid pan. The samples were diluted and cultivated on nutrient agar with different salt concentrations (5-%53), then the plates were incubated at %5-07 ºC in aerobic conditions for 4 days. In total 975strains were grew on media including 5-%53 salt concentrations. Of all isolates %1 strains were hyperhalophilic and moderately thermophilic and can grew on media including 97-%53 salt concentrations in 47-07 °С of temperature. These strains were screened for amylase production. Based on differences in enzyme production by clear zone on the plates with the addition of KI% reagent, the highest amylase producer was chosen for further investigation which was originated in soils of region% (vegetation) from Howz Soltan lake. This strain can grew on media including 6-923 salt concentrations (%.7 and 5.7 M NaCl) at temperature %5-65 °С. The maximum enzyme activity at 41h was observed to be %1.%45U/ml and the optimal pH and temperature and NaCl concentration for amylase production were 0.7-0.5 and 474C and %53 (9.5M) respectively. Taxonomic and Phylogenetic analysis using %6SrRNA gene sequences revealed that belong to Bacillus licheniformis. It was first study about the isolation of Halothermophilic Bacillus licheniformis as the Halophilic bacteria in Howz Soltan salt lake of Iran. Its property makes this strain and enzyme a potential candidate to be employed in applications requiring high salt concentration and stress.

کلیدواژه ها:

Halophilic bacteria ، Thermophilic bacteria ، Amylase of bacteria