Reference "Structure of wheat serine carboxypeptidase II at 3.5-A resolution. A new class of serine proteinase"

Reference ID

9076

Title

Structure of wheat serine carboxypeptidase II at 3.5-A resolution. A new class of serine proteinase

Source

The Journal of biological chemistry, 1990, vol. 265, pp. 6528-6531

Authors (2)

Liao-D-I

Remington-S-J

Abstract

The structure of serine carboxypeptidase II from wheat bran has been determined
to 3.5-A resolution by multiple isomorphous replacement, solvent flattening, and
crystallographic refinement. The amino acid sequence has been fit to the
electron density map and the model refined to a conventional crystallographic R
factor of 20.9%. The molecule is an alpha + beta protein and contains a
"catalytic triad" (Asp338, His397, and Ser146) similar in arrangement to those
in chymotrypsin and subtilisin. The -fold of the polypeptide backbone is,
however, completely different from those enzymes. This suggests that this is a
third example of convergent evolution to a common enzymatic mechanism. The -fold
is, on the other hand, surprisingly similar to that of the zinc proteinase
carboxypeptidase A.