A lipase-inhibiting protein from lipoxygenase-deficient soybean seeds.
A lipase-inhibiting protein was isolated from lipoxygenase (LOX)-deficient soybean seeds. The molecular mass of the protein was 56.0-kDa and the N-terminal amino acid was blocked. The protein was identified by peptide mass fingerprinting in combination with matrix-assisted laser desorption ionization/time-of-flight mass spectrometry. The masses of the lysyl endopeptidase-digested peptides of the 56.0-kDa inhibiting protein were almost identical to the calculated masses of the theoretically predicted lysyl endopeptidase-treated peptides of beta-amylase from soybean seed. In a previous paper (Biosci. Biotechnol. Biochem., 62, 1498-1503, 1998), we reported that LOX-1, an isozyme of soybean seed LOX, inhibited hydrolysis of soybean oil by pancreatic lipase. Purified beta-amylase also inhibited lipase activity, although the magnitude of inhibition was weaker than that by LOX-1. Thus, there are at least two lipase-inhibiting proteins, one is a LOX and the other is a beta-amylase, in soybean seed.
Satouchi
Kiyoshi
K
Department of Applied Biological Science, Fukuyama University, Fukuyama 729-0292, Japan. satouchi@fubac.fukuyama-u.ac.jp
Kodama
Yoshifumi
Y
Murakami
Kaoru
K
Tanaka
Tamotsu
T
Iwamoto
Hiroyuki
H
Ishimoto
Masao
M
D000595:Amino Acid Sequence; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D008049:Lipase / Q000037:antagonists & inhibitors*; D008084:Lipoxygenase / Q000172:deficiency*; D008969:Molecular Sequence Data; D012639:Seeds / Q000187:drug effects / Q000201:enzymology; D013025:Glycine max / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D001614:beta-Amylase / Q000032:analysis / Q000378:metabolism
D004791:Enzyme Inhibitors; D008084:Lipoxygenase; D008049:Lipase; D001614:beta-Amylase