Catabolism of C 14 -Labelled Glucose, Gluconate and Acetate in Verticillium albo-atrum

Abstract

Brandt, W. H., and C. H. Wang. (Oregon State College, Corvallis.) Catabolism of C14-labelled glucose, gluconate and acetate in Vertieillium albo-atrum. Amer. Jour. Bot. 47(1): 50—53. Illus. 1960.–The major catabolic pathways of glucose in conidia from rapidly proliferating shake-cultures of Verticillium albo-atrum Reinke and Berth, isolated from okra and cultured under light at 25°C. have been identified and estimated from data obtained by the radiorespirometric method. When pure oxygen was used as a sweep gas, glucose appeared to be catabolized approximately 60% via the Embden-Meyerhof-Parnas glycolysis (EMP) and 40% via phosphogluconate decarboxylation (PGD). With air as the sweep gas, about 48% of the glucose was catabolized via the EMP pathway and about 52% via the PGD pathway. Glucose was catabolized under a pure nitrogen atmosphere, but there was little PGD, operating under these conditions. Gluconate was rapidly decarboxylated in the C-l position, but only a small proportion of carbon atoms from other positions appeared in the respiratory CO2. Acetate was utilized readily in such a way that the operation of the tri-carboxylic acid cycle may be inferred. Pyruvate was used slowly because it appeared to enter the conidia slowly.