Activity of polyamine biosynthesis enzymes in Escherichia coli isolates

The ability of Escherichia coli isolated from different habitats to decarboxylate lysine, ornithine, and arginine was studied. The decarboxylase activity is widespread among Escherichia coli, since only 7% of the isolates showed no ability to decarboxylate any of the three amino acids. The ability to decarboxylate arginine was less common than the ability to decarboxylate lysine or ornithine. Natural isolates were characterized by different combinations of arginine, ornithine, and lysine decarboxylase activity. The most common combination was lysine decarboxylase and ornithine decarboxylase activity, while the combination of ornithine decarboxylase and arginine decarboxylase activity, in the absence of decarboxylation of lysine, was not detected. There were no differences in the decarboxylase activity patterns of isolates from different sources.