Generation of a different type of beta-kallikrein from porcine pancreatic alpha-kallikrein by the action of chymotrypsin--observation of proteolytic processing occurring around "kallikrein autolysis loop" region.
The generation of a different type of beta-kallikrein, designated C beta-kallikrein, from alpha-kallikrein by chymotryptic action was ascertained by the following observations: 1) When alpha-kallikrein was incubated with chymotrypsin, an increase of esterolytic activity of kallikrein was observed. 2) In sodium dodecyl sulfate polyacrylamide gel electrophoresis, C beta-kallikrein was found to be different from the beta-kallikrein obtained from alpha-kallikrein by tryptic digestion, and was designated T beta-kallikrein. 3) N-Terminal amino acid sequence analyses of internal light and heavy chains of C beta-kallikrein indicated that N-termini of the light and the heavy chains were isoleucine and lysine, respectively, and that the heavy chain had most of the "kallikrein autolysis loop" sequence in its N-terminal end. In the case of T beta-kallikrein, N-termini of the light and the heavy chains were isoleucine and alanine, respectively, and the light chain retained the "kallikrein autolysis loop" region in its C-terminal end. These observations demonstrated that C beta-kallikrein was different from the beta-kallikrein prepared from autolyzed pancreas, A beta-kallikrein, which had lost the "kallikrein autolysis loop" sequence. Structural differences of the above four kallikreins (alpha-, T beta-, C beta-, and A beta-) result in somewhat different enzyme properties. The kinetic constants for the hydrolysis of synthetic substrates (N alpha-benzoyl-L-arginine ethyl ester and N alpha-tosyl-L-arginine methyl ester) of these kallikreins differed from each other, and inhibitory profiles against alpha 1-antitrypsin were also different.(ABSTRACT TRUNCATED AT 250 WORDS)
Kamada
M
M
Department of Biochemistry, Faculty of Pharmaceutical Sciences, Science University of Tokyo, Japan.
Ikekita
M
M
Kurahashi
T
T
Aoki
K
K
Kizuki
K
K
Moriya
H
H
Sweeley
C C
CC
Kamo
M
M
Tsugita
A
A
D000595:Amino Acid Sequence; D000818:Animals; D002918:Chymotrypsin / Q000378:metabolism*; D007527:Isoenzymes; D007610:Kallikreins / Q000032:analysis*; D008969:Molecular Sequence Data; D013329:Structure-Activity Relationship; D013552:Swine
D007527:Isoenzymes; D007610:Kallikreins; D002918:Chymotrypsin