The free amino acid pool composition during growth of the culture of Xanthomonas citri (Hasse) Dowson.

Fourteen amino acids were found to constitute the intracellular amino compound pool of the developing culture of Xanthomonas citri (Hasse) Dowson. These were serine, dl-alanine, beta-alanine, leucine/isoleucine, threonine, aspartic acid, glutamic acid, asparagine, glutamine, cystine, histidine, tyrosine, tryptophan, and proline. Of these, beta-alanine, threonine, aspartic acid, glutamic acid, asparagine, and tyrosine could be traced as excretory amino acids in the bacterial culture filtrate, being exuded at the cost of and parallel to the depletion of their amounts in bacterial cell extract. Thus, the composition and pool size of intra- and extracellular amino acids varies considerably during the growth of this pathogen. The wall constituents of X. citri, especially alanine, glutamic acid, and aspartic acid, were prominent among the amino compounds detected.