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Hamid B, Jehangir A, Baba ZA, Wani MA, Khan I.2019. Isolation and characterization of psychrotrophic proteolytic bacteria from landfill site under temperate climatic conditions of Kashmir Himalaya. PeerJ Preprints7:e27391v2https://doi.org/10.7287/peerj.preprints.27391v2
The temperate climatic regions face the problem of waste accumulation due to lower environmental temperatures. However, these regions harbor cold active microbes viz. psychrotrophic proteolytic bacteria that play an important role in the degradation of protenaceous materials of the waste stream. Hence in the present study psychrotrophic proteolytic bacteria were isolated from waste samples collected from landfill site by using random sampling method under environmental temperature of 10oC. By using serial dilution and spread plate technique a total of 8 morphologically different psychrotrophic proteolytic bacteria were isolated on skim milk agar media at pH of 7.0 and temperature of 10°C after 48hours. Under in-vitro conditions all the isolates produced significant quantities of protease over the control and diameters of hydrolysis zones ranged between 2 to 18 mm at temperature range of 5 to 20oC and after 72 hours. The corresponding quantitative protease activities of the isolates was significant that ranged between 0.5 to 2.25 U/ml and the isolate PB2 was most efficient with highest protease activity of 2.25U/ml at 20oC. Based on 16SrRNA analysis the isolate was identified as Pseudomonas florescence with 96% similarity. It was concluded that the isolates can grow in wide ranges of temperature and could be used for enhanced decomposition of organic wastes during lower temperature conditions in cold regions. Further the isolates could have industrial applications due to the production of cold active proteases that would help economic benefits through energy conservation.
Between the previous and new manuscript there are many changes. For example, we added many tables regarding the ability of the isolate to utilize many substrates, effect of inhibitors on enzyme activity and a new figure mentioning the molecular weight of the enzyme.