Cleavage specificity of cucumisin, a plant serine protease.
Cucumisin was isolated from prince melon sarcocarp by means of a simple purification procedure. Serine protease inhibitors such as soybean trypsin inhibitor, ovomucoid, and aprotinin had no effect on the enzyme activity. alpha 2-Macroglobulin showed 38% inhibition of the original caseinolytic activity of cucumisin. The favorable synthetic substrates for cucumisin were Glt-Ala-Ala-Pro-Leu-pNA and Suc-Ala-Ala-Pro-Phe-pNA. The constant (kcat/Km) for Suc-Ala-Pro-Ala-pNA was found to be 30 times greater than that for Suc-Ala-Ala-Ala-pNA. The substrate specificity of cucumisin for oligopeptides and proteins was shown to be broad.
Uchikoba
T
T
Department of Chemistry, Faculty of Science, Kagoshima University.
Yonezawa
H
H
Kaneda
M
M
D000595:Amino Acid Sequence; D000814:Aniline Compounds / Q000737:chemistry; D001665:Binding Sites; D004795:Enzyme Stability; D005638:Fruit / Q000737:chemistry; D006358:Hot Temperature; D006868:Hydrolysis; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000737:chemistry / Q000378:metabolism; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D010940:Plant Proteins / Q000737:chemistry / Q000378:metabolism; D012697:Serine Endopeptidases / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D013379:Substrate Specificity; D013696:Temperature
D000814:Aniline Compounds; D009842:Oligopeptides; D010455:Peptides; D010940:Plant Proteins; D012697:Serine Endopeptidases; C041541:cucumisin