Glycolytic and respiratory enzymes of Trichophyton mentagrophytes.

Although the dermatophytes are common fungal pathogens, very little is known concerning their metabolic systems. Biochemical studies with this group have been limited primarily to the nutritional requirements (Robbins et al., 1942; Schopfer and Blumer, 1943; Robbins and Ma, 1945; Georg, 1950; Benham, 1953; Silva, 1953; and Silva and Benham, 1954) and the demonstration of various extracellular enzymes (Tate, 1929). Respiration studies were first conducted by Nickerson and Chadwick (1946) in which the effects of substrate and pH upon oxygen uptake were determined. Further studies by Bentley (1953) have shown that acetone extracts of four dermatophytes will oxidatively deaminate amino acids. Chattaway et al. (1954) have measured the rate of oxygen consumption by cell free extracts of Microsporum canis in the presence of various intermediates of carbohydrate metabolism. Significant activity was detected in the presence of glucose, suceinate, citrate, pyruvate, fumarate, acetate, and oxalacetate. Amino acid oxidase activity in the presence of DL-methionine, L-aspartic acid, DL-alanine, L-leucine, and DL-glutamic acid was also detected. This study was undertaken to determine more completely the metabolic pathways which exist in the dermatophyte, Trichophyton mentagrophytes. Preliminary manometric studies with intact mycelium were condueted but were discontinued because of the high endogenous respiration which made it difficult to obtain useful analytical data. This problem has been described by practically all investigators in this field and appears to be common to all filamentouis fungi. Aeration in substrate free solutions for extended periods of time invariably leads to substantial loss of respiratory capacity, both endogenous and in the presence of substrate. In order to circumvent this problem the measurement of specific enzyme in cell free extracts of this organism was pursued. Enzymes of the hexosediphosphate system, the tricarboxylic acid cycle, and the hexosemonophosphate pathway are described, along with several others noted.