A moderately cold active, extracellular alkaline protease producing bacterium was isolated from a fresh water lake. The isolate was found to be a gram-positive, rod shaped organism later identified as Bacillus cereus MTCC 6840. The bacterium produced the maximum amount of enzyme when allowed to grow for 24 h at temperature 25º and pH 9.0. Among a variety of substrates used, fructose as a carbon source and a combination of yeast extract and peptone as nitrogen source, supported the maximum protease production by the organism (120 U/ml). Fe ++ and Co ++ stimulated the enzyme activity whereas Ca ++ , Cu ++ , K + , Mg ++ and Mn ++ inhibited it to different extents. The protease was found to be highly stable in the presence of NaCl, SDS and acetone. Treatment with EDTA and PMSF resulted in the considerable loss of enzyme activity. The enzyme was found to be optimally active at pH 9.0 and temperature 20ºC.
A moderately psychrophilic bacterium Corynebacterium paurometabolum MTCC 6841 (gram positive, short rod type) producing extracellular alkaline lipase was isolated from Lake Naukuchiatal, Uttaranchal, India. The bacterium was able to grow within a broad range of pH (5-10). Soyabean oil and olive oil served as the best carbon sources for lipase production. The bacterium preferred inorganic nitrogenous compounds, NaNO3 and KNO3, over organic nitrogenous compound for its growth. Maximum lipase production occurred at 25 degrees C and 8.5 pH. The enzyme activity was found to be maximum at the same values of temperature and pH. The enzyme was reasonably stable in the presence of various organic solvents. No significant effect of Ca+, Cu++, Fe++, Na+, K+, Mg++, Mn+, NH4+, Co++ ions over enzyme activity was detected. Treatment with EDTA reduced the activity to nearly one half.
The growth and protease production by Bacillus sp. (SBP-29) was examined for poultry processing industries. The maximum protease activity was 3028 U/mL using 1.5% (w/v) of soybean meal as substrate. Soybean meal is an inexpensive and readily available, thus it can be used as the cost effective crude material for the production of an extracellular protease. Inorganic nitrogen sources proved to be less favorable, for protease production as strong catabolic repression was observed with ammonium ions. A maximum of 3208 U/mL of protease was produced in 18 h in a 10L bioreactor. The enzyme has temperature and pH optima of 60°C and 9.5 respectively. However, the temperature stability range is from 20-90 °C and pH stability range is from 6.0-12.0. The protease was completely inhibited by phenylmethylsulfonyl fluoride (PMSF) and diodopropyl fluorophosphate (DFP), with little increase (10-15%) in the production of upon addition of Ca ++ and Mg ++ .
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.