Soybean callus

Feung, C. S., Hanrilton, R.H., and Mumma, R.O. Metabolism of 2,4-dichlorophenoxyacetic acid. V. Identification of metabolites in soybean callus tissue cultures. J. Agric. Food Chem., 21(4) 637-640, 1973. 

Larsen, K. Jochimsen, B.U. (1986). Expression of nodule-specific uricase of soybean callus tissue is regulated by oxygen. The EM BO Journal 5, 15-19. 

A long-chain dihydroxy compound, isolated from Avocado mesocarp, inhibited soybean callus growth and induced elongation of wheat coleoptiles. This compound was identified as 1-acetoxy-2,4-dihydroxy-n-heptadeca-16-ene, otherwise known as avocado inhibitor (14). 

Botran was one of the first xenobiotics reported to be metabolized to an N-malonyl conjugate by this mechanism In plant tissues (120) (Equation 28). The N-malonyl conjugate of botran was the major metabolite In both soybean and soybean callus culture. It was Isolated by chromatographic methods and Identified by synthesis and by chemical and mass spectral methods. 

Quantitative differences in 2t4-D metabolism were also observed as a result of herbicide concentration and tissue age in soybean callus cultures (31). Unmetabolized 2(4-D constituted most of the extracted from three-wedc old callus tissue, and the concentration of free 2.4-D increased 32-fold in the tissue as external 2.4-D concentration was increased from 10 ° to 10 M (Figure 3). Aqueous (glycosides) and ether soluble metabolites (amino acid conjugates) were present in lower amounts, and increased slowly over the 10 ° to 10 M concentration range. In nine-week old callus cultures, ether soluble metabolites (2.4-D amino acid conjugates) were the major components of the tissue, and increased four-fold over a three-fold increase in 2.4-D concentration in the external medium (Figure 3). The concentration of 2.4-D remained low and relatively constant as it was converted to amino acid conjugates. Aqueous soluble metabolites formed a relatively minor component in nine-week old callus. 

Studies of 2.4.5-T [(2,4,5-trichlorophenoxy)acetic acid] metabolism in soybean callus tissue also showed that formation of amino acid conjugates was a major metabolic fate of the herbicide... 

No direct comparisons were made with soybean plants in that study, but others have reported decarboxylation (36). hydroxylation (37, 38), and glycoside formation of 4 OH-2,5-D (39) as minor metabolites in various plant species. Minor metabolites were detected, but not identified in soybean callus tissue (35). 

Chlorophyll synthesis of initially etiolated soybean callus considerably increases under the influence of oxyge-... 

Effects of 12-hydroxy-9(Z) -dodecenoic and traumatic acids (10 M) on chlorophyll accumulation during greening of initially etiolated soybean callus. 

Biotests for the detection and quantitative measurement of C. measure one of the following 1. stimulation of cell division in tissue cultures, e.g. in tobacco or soybean callus tissue 2. enlargement of cells in the leaf disc test, often with bean or radish leaves 3. inhibition of the loss of chlorophyll from detached leaves 4. promotion of seed germination in the dark. 

Studies of the Mode of Action of Cytokinin in Cytokinin-Dependent Cell Suspension Cultures of Soybean Callus... 

Soybean callus of cotyledonary origin (cv Acme) is a principal bioassay for cytokinins [31] with an unusually stable, absolute requirement of cell division for cytokinin. We choose to use it in suspension culture in order to obtain synchronous activation of all cells, allowing us to investigate early events. 

Fig. 2. Effect of anti-calmodulin drugs and Ca- + -channel blockers on cell proliferation in suspension cultures of soybean callus supplied with cytokinin. Cells in the linear phase of the batch growth cycle were suspended at 0.4 X 10 cells/ml. Cell number and viability were estimated after 6 days of culture using methods described in reference [34]. D-600 and verapamil were a generous gift of Knoll A.G., Ludwigshafen am Rhein, FRG...

Table 2. Effect of the Ca-"-ionophore A23187 on cell number and cell viability in cytokinin-responsive samples of suspension-cultured soybean callus 6 days after addition...

Blumenfeld A, Gazit S (1970) Interaction of kinetin and abscisic acid in the growth of soybean callus. Plant Physiol 45 535-536... 

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