Partial purification and characterization of serine protease produced through fermentation of organic municipal solid wastes by Serratia marcescens A3 and Pseudomonas putida A2

Abstract

Proteolytic bacteria isolated from municipal solid wastes (MSW) were identified as Serratia marcescens A3 and Pseudomonas putida A2 based on 16S rDNA sequencing. Protease produced through fermentation of organic MSW by these bacteria under some optimized physicochemical parameters was partially purified and characterized. The estimated molecular mass of the partially purified protease from S. marcescens and P. putida was approximately 25 and 38 kDa, respectively. Protease from both sources showed low Km 0.3 and 0.5 mg ml−1 and high Vmax 333 and 500 µmole min−1 at 40 °C, and thermodynamics analysis suggested formation of ordered enzyme-substrate (E-S) complexes. The activation energy (Ea) and temperature quotient (Q10) of protease from S. marcescens and P. putida were 16.2 and 19.9 kJ/mol, and 1.4 and 1.3 at temperature range from 20 to 40 °C, respectively. Protease of the both bacterial isolates was serine and cysteine type. The protease retained approximately 97% of activity in the presence of sodium dodecyl sulphate. It was observed that the purified protease of S. marcescens could remove blood stains from white cotton cloth and degrade chicken flesh remarkably. Our study revealed that organic MSW can be used as raw materials for bacterial protease production and the protease produced by S. marcescens A3 might be potential for applications.

Production and partial characterization of dehairing alkaline protease from Bacillus subtilis AKAL7 and Exiguobacterium indicum AKAL11 by using organic municipal solid wastes

“…About 16,000 tons of solid wastes are produced every day from the six divisional cities and other urban areas of Bangladesh ( Bahauddin and Uddin, 2012 ). It is predicted that this amount will be up to 47,000 tons per day by 2025 due to increase in population and urbanization ( Bahauddin and Uddin, 2012 ; Iqbal et al., 2018 ). Methane, the second most prevalent greenhouse gas having impact on climate change over 20 times greater than carbon dioxide is emitted from the rotten MSW ( EPA, 2013 ).…”

“…Almost 70–80% of the MSW is organic materials, which are mainly composed of cellulose, protein and fat ( Alamgir and Ahsan, 2007 ; Hasan et al., 2017 ). The large amount of organic MSW (OMSW) can be used for production of commercially important enzymes as well as renewable biomass energy and thereby to mitigate the climate change, public health hazards and environmental pollution caused by unmanaged MSW ( Azad et al., 2013 , 2014 ; Iqbal et al., 2018 ).…”

“…Reducing the cost of enzyme production by optimization of fermentation medium and process parameters is the major goal of basic research for industrial applications ( Li et al., 2006 ). In our previous studies, the inexpensive cellulosic and proteinous materials of MSW were used as carbon and nitrogen sources in fermentation for neutral protease production by bacterial isolates ( Azad et al., 2013 ; Iqbal et al., 2018 ). However, because the alkaline protease has wide range of industrial applications, our target is to produce alkaline protease from new bacterial isolates by using OMSW.…”

Kinetics of casein hydrolysis by peptidase from Bacillus thuringiensis var. israelensis

“…The obtained k m values are quite low compared to most of microbial proteases (0.3-19.2 g/l) [1,3,18,19].…”

Novel extremophilic proteases from Pseudomonas aeruginosa M211 and their application in the hydrolysis of dried distiller's grain with solubles

“…It was reported previously that the majority of proteases from Pseudomonas species isolated from different environments have been classified either as metalloproteases 6,18,19,36,41,43,[45][46][47][48] or serine proteases. 42,49,52 However, to the best of our knowledge, it is the first time that extracellular serinemetalloproteases from P. aeruginosa have been reported.…”