Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2016 Jul;20(4):395-402.
doi: 10.1007/s00792-016-0830-1. Epub 2016 Apr 25.

Molecular characterization and growth optimization of halo-tolerant protease producing Bacillus Subtilis Strain BLK-1.5 isolated from salt mines of Karak, Pakistan

Affiliations

Molecular characterization and growth optimization of halo-tolerant protease producing Bacillus Subtilis Strain BLK-1.5 isolated from salt mines of Karak, Pakistan

Nawab Ali et al. Extremophiles. 2016 Jul.

Abstract

Microbial proteolytic enzyme is one of the most important industrial enzymes that hydrolyze proteins. The applications of proteases under harsh industrial conditions like alkalinity, salinity, and temperature make them inactive and unstable. This suggests need for search for novel microbial sources for protease production having diverse properties. For this purpose, 54 bacterial strains were isolated from different salt mines of Karak, Pakistan and were investigated for their proteolytic activity on skim milk agar plates. The strain which showed maximum protease activity was characterized by 16S rRNA gene sequence analysis. Furthermore, growth and protease production was optimized for the characterized bacteria under different physical factors, i.e., pH, temperature and salinity. The isolate BLK-1.5 exhibited strong protease production and was identified as Bacillus subtilis based on biochemical characteristics and 16S rRNA gene sequence analysis. Maximum production of protease was recorded at pH 10, 37 °C and 7 % (w/v) NaCl. Molecular weight of proteases was estimated 38 kDa and its optimum activity was observed at pH 10, 50 °C and 2 % (w/v) NaCl. In conclusion, the protease produced by halo-tolerant Bacillus subtilis strain BLK-1.5 has diverse characteristics and could be useful in various industrial applications.

Keywords: 16S rRNA gene; Halo-tolerant; Proteolytic enzyme; Salt mines.

PubMed Disclaimer

References

    1. Nature. 1970 Aug 15;227(5259):680-5 - PubMed
    1. Extremophiles. 2001 Apr;5(2):73-83 - PubMed
    1. J Ind Microbiol Biotechnol. 2009 Mar;36(3):333-40 - PubMed
    1. Mol Biol Evol. 2013 Dec;30(12):2725-9 - PubMed
    1. Appl Biochem Biotechnol. 2006 Jul;134(1):77-87 - PubMed

MeSH terms

LinkOut - more resources