Structural comparison of psychrophilic and mesophilic trypsins

摘要: Structural rationalizations for differences in catalytic efficiency and stability between mesophilic cold-adapted trypsins have been suggested from a detailed comparison of eight trypsin structures. Two trypsins, Antarctic fish Atlantic cod, constructed by homology modeling techniques compared with six existing X-ray structures both trypsins. The structural analysis focuses on the cold residue determinants found more extensive 27 sequences, reveals number features unique to increased substrate affinity psychrophilic is probably achieved lower electrostatic potential S1 binding pocket particularly arising Glu221B, lack five hydrogen bonds adjacent triad. reduced expected arise packing two distinct core regions, fewer interdomain destabilized C-terminal α-helix. helices four salt-bridges, they poorer van der Waals interactions body molecule, counterparts.