Protease Composition in Tissue Extracts of Hydrobionts from Antarctic Region: Recent Study

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 then 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. Based on this analysis, the proteolytic enzymes in
extract of O. validus might 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.