STM Article Repository

Aims: Marine hydrobionts which grow in extreme conditions, e.g. low temperatures are an important source of enzymes with unique properties. By this reason the proteases from cold-water organisms could have a considerable biotechnological and, therefore, commercial significance. The objective of the current study was to investigate the proteolytic potential of marine hydrobionts from Antarctic region (an example of Odontaster validus and Glyptonotus antarcticus).

Methodology: SDS-PAGE was carried out for the determination of protein composition in extracts. The proteolytic activity was monitored by zymographic technique. Further the samples were preincubated with protease inhibitors EDTA, PMSF and SBTI and than total proteolytic (with casein as substrate) activity was measured. Gel filtration chromatography was applied for the fractionation of tested extracts. Collagenolytic and trypsin-like (amidase activity) activities were assessed with help of native collagen type I and L-BApNA respectively.

Results: The results of gelatin zymography provided evidence for the presence of active enzymes in extracts of both hydrobionts whereas fibrinogen zymography revealed the presence only one clear area in extract of O. validus. Specific protease inhibitors were used to identify the nature of proteases present in tissue of investigated hydrobionts. On the basis of this analysis, the proteolytic enzymes in extract of O. validus may be classified as metal-dependent proteases, whereas the enzymes in extract of G. antarcticus were most likely trypsin-like proteases. Tissue extracts were separated by gel filtration chromatography on seven fractions for O. validus and six fractions for G. antarcticus. Further enzymatic activity assay in obtained fractions revealed that both hydrobionts possessed significant collagenolytic activity which was detected in the first four fractions.

Conclusion: The current study gives some information about protease composition in tissue extracts of hydrobionts of Antarctic region. It could be useful for better understanding of functional and catalytic characteristics of proteases from cold-water organisms.