The effect of 2,4-D and kinetin on the activity and isoenzyme pattern of various enzymes in cotyledon cell suspension cultures of bush bean (Phaseolus vulgaris cv. Contender)

Abstract

Changes in the activity and isoenzyme patterns of acid phosphatase, leucine aminopeptidase, glutamate-oxaloacetate transaminase, esterase, and malate and glutamate dehydrogenases were studied in cotyledon cell suspension cultures of Phaseolus vulgaris grown in the presence and absence of the growth regulators 2,4-dichlorophenoxyacetic acid and kinetin. With all enzymes studied, the pattern of isoenzymes and total enzymatic activity changed with the different phases of the culture cycle. In particular, the patterns of esterase, malate dehydrogenase, and glutamate dehydrogenase changed markedly with the inoculation of cells into fresh medium.The differences in isoenzyme patterns of cells grown with and without regulators were predominantly quantitative. However, certain minor isoenzymes of acid phosphatase, glutamate-oxaloacetate transaminase, esterase, and malate dehydrogenase were only detected in cultures grown in the presence of the regulators, while one isoenzyme of leucine aminopeptidase and two of esterase were unique to cells cultured in the absence of regulators.Three cathodic isoenzymes of acid phosphatase were released from wall material by 1 M NaCl. Such isoenzymes were also detected in the medium and in cytoplasmic extracts. Increase in the wall isoenzymes following inoculation into fresh medium was correlated with a decrease in anodic, cytoplasmic acid phosphatase.