Summary
Studies on the degradation of 6,7-dimethylquinoxaline-2,3-diol-(methyl-14C) by Pseudomonas RF are described. Evidence is presented that this degradation product of riboflavin is assimilated by at least two different pathways which are affected by growth conditions. One leads to the previously identified 3,4-dimethyl-6-carboxy-α-pyrone and the other to intermediates which in turn are metabolized to various cell constituents.
Analyses of amino acids from protein hydrolysates and organic acids excreted into the medium disclosed the presence of 14C-labelled alanine, butyrate, propionate and acetate, all predominantly labelled in the terminal methyl group. Results of studies with various inhibitors of the two pathways are given and the data are compared with previous work on this organism. A scheme for bacterial degradation of 6,7-dimethylquinoxaline-2,3-diol is postulated.
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Barz, W., Stadtman, E.R. Bacterial degradation of riboflavin. Archiv. Mikrobiol. 67, 128–140 (1969). https://doi.org/10.1007/BF00409678
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DOI: https://doi.org/10.1007/BF00409678