Psychrophiles are cold-adapted microorganisms living in cold regions and are known to generate cold-active enzymes such as proteases, lipases, and peptidases. These types of enzymes are a major part of the market of the food and textile sector. This study aimed to isolate and characterize the cold-active and detergent-stable, extracellular protease from psychotrophic bacteria Serratia sp. TGS1 (OQ654005). Protease was purified by gel permeation chromatography using Sephadex G-75. The specific activity of the purified protease was 250 U/mg at 15 & DEG;C, with a purification fold of 5.68 and a percentage yield of 60%. The cold active protease was stable within a temperature range of 5-30 & DEG;C and a pH range of 6-10. Ca+2 and Mg+2 enhanced its activity while chelators like ethylenediaminetetraacetic acid inhibited cold active protease, showing it as metalloprotease in nature. The enzyme was sensitive to Cu+2, Zn+2, and Hg+2, and the proteolytic activity decreased upon treatment with heavy metals. The molecular weight of the protease was estimated to be 47 kDa using sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. Proteins within a specific range of molecular weight possess desirable properties for industrial enzyme use. By working on a specific range, the researchers intended to examine an enzyme to examine its specific characteristics. The purified protease showed high stability to detergents like SDS, Tween 20, Tween 60, and Triton X. The maximum velocity V-max and K-m values were 59.90 mg/min/mL and 1.53 mg/mL, respectively. The obtained protease exhibited an interesting activity at a broad range of pH (6-10) and stability at low temperatures (5-30 & DEG;C) and detergents. Such enzymatic features of versatile and potent cold-active enzymes enhance their industrial applications to meet food, dairy, and laundry requirements.
The Arctic is warming - fast. Microbes in the Arctic play pivotal roles in feedbacks that magnify the impacts of Arctic change. Understanding the genome evolution, diversity and dynamics of Arctic microbes can provide insights relevant for both fundamental microbiology and interdisciplinary Arctic science. Within this synthesis, we highlight four key areas where genomic insights to the microbial dimensions of Arctic change are urgently required: the changing Arctic Ocean, greenhouse gas release from the thawing permafrost, 'biological darkening' of glacial surfaces, and human activities within the Arctic. Furthermore, we identify four principal challenges that provide opportunities for timely innovation in Arctic microbial genomics. These range from insufficient genomic data to develop unifying concepts or model organisms for Arctic microbiology to challenges in gaining authentic insights to the structure and function of low-biomass microbiota and integration of data on the causes and consequences of microbial feedbacks across scales. We contend that our insights to date on the genomics of Arctic microbes are limited in these key areas, and we identify priorities and new ways of working to help ensure microbial genomics is in the vanguard of the scientific response to the Arctic crisis.
Microorganisms in cold ecosystems play a key ecological role in their natural habitats. Since these ecosystems are especially sensitive to climate changes, as indicated by the worldwide retreat of glaciers and ice sheets as well as permafrost thawing, an understanding of the role and potential of microbial life in these habitats has become crucial. Emerging technologies have added significantly to our knowledge of abundance, functional activity, and lifestyles of microbial communities in cold environments. The current knowledge of microbial ecology in glacial habitats and permafrost, the most studied habitats of the cryosphere, is reported in this review.