Anchovy trypsin: purification, cDNA cloning, and molecular modeling of two isoforms

Abstract

Because of its numerous industrial and research application trypsin is by far the most thoroughly characterized enzyme. Interestingly, trypsins from cold-adapted marine fish show substantially higher catalytic efficiencies than their mammalian equivalents. Two isoforms of trypsin purified from anchovy appeared to be catalytically more active than bovine trypsin with one isoform being as much as 35 times more efficient. Primary structural alignment revealed some noteworthy features, which were further substantiated by comparative three-dimensional structural modeling. Two unique deletions in autolysis loop, lack of Tyr-151 pointing toward the S1 pocket and electrostatic surface potentiality around S1 pocket of anchovy trypsin have been discussed with regard to their structural significances compared to bovine trypsin. The molecular mechanisms underlying this uniqueness are still under speculation, but such knowledge would be invaluable in understanding the structural plasticity of enzyme function as well as for the development of an enzyme with novel specificity.