Characters of two gravity-related esterases in carrot callus cells

• Published in: Zhíwù shenglì xuébào Vol. 25; no. 3; p. 301
• Main Authors: Guan, P Z, Fei, C K, Yin, J, Liu, M, Zhao, Q, Cai, W M
• Format: Journal Article
• Language: Chinese
• Published: China 1999
• Subjects: Copper Sulfate - pharmacology; Cysteine - pharmacology; Daucus carota - cytology; Daucus carota - drug effects; Daucus carota - enzymology; Deoxycholic Acid - pharmacology; Esterases - chemistry; Esterases - drug effects; Esterases - isolation & purification; Esterases - metabolism; Gravitation; Isoelectric Point; Molecular Weight; Phenylpropionates - pharmacology; Plant Proteins - chemistry; Plant Proteins - drug effects; Plant Proteins - isolation & purification; Plant Proteins - metabolism; Silver Nitrate - pharmacology; Sodium Dodecyl Sulfate - pharmacology
• ISSN: 0257-4829

On the basis of identification of two gravity-related esterases (grEST1 and grEST2) in carrot callus cells (Cai et al. 1998), we continued the study of the characteristics of these two esterases. They have the very special characteristic of SDS resistance. Their activities could be inhibited partially by deoxycholate. beta-Phenylpropionic acid, AgNO3 and CuSO4 had no inhibitory effect on their activities. The activities of grEST1 and grEST2 could be decreased by ascorbic acid and cysteine, and the influence by cysteine was particularly obvious. The molecular weights of grEST1 and grEST2 were shown to be near the ranges of 49-66 kD and 43-59 kD respectively by non-denaturing electrophoresis containing deoxycholate, Triton X-100 and SDS respectively, and the isoelectric points were approximately pH 5.4 and 4.9 respectively. Besides, grEST1 and grEST2 were found in the fraction precipitating at value between 30% and 40% saturation with (NH4)2SO4.