FUNCTION OF THE ARGININE OXYGENASE PATHWAY IN UTILIZATION OF L-ARGININE-RELATED COMPOUNDS IN ARTHROBACTER-GLOBIFORMIS AND BREVIBACTERIUM-HELVOLUM

Two coryneform bacteria, Arthrobacter globiformis IFO 12137 (ATCC 8010 ) and Brevibacterium helvolum IFO 12073, which have the arginine oxyge nase pathway, could utilize L-ornithine, L-citrulline, and D-arginine. The cells of the bacteria grown on these amino acids contained high l evels of guanidinobutyrase and induced levels of the enzymes of the pr eceding steps of the pathway. 4-Guanidinobutyrate induced guanidinobut yrase but failed to induce the other enzymes, indicating that it was t he direct inducer of guanidinobutyrase. These amino acids and L-argini ne also induced L-arginine:2-ketoglutarate aminotransferase. 4-Aminobu tyrate was formed on incubation Of L-citrulline With L-citrulline-grow n cells of A. globiformis in the presence of gabaculine; its amount wa s about 50% of the L-citrulline degraded. The L-arginine-grown cells p roduced 4-aminobutyrate and urea from L-arginine in the presence of am inooxyacetate or gabaculine; the amount of 4-aminobutyrate was 80% or more of that of the L-arginine degraded. When the oxygenase pathway wa s blocked with thioglycolate, the degradation of L-arginine and the fo rmation of urea and 4-aminobutyrate were greatly suppressed. These res ults indicate that these amino acids are degraded via the arginine oxy genase and the arginine aminotransferase pathways and the major route is the former. Agmatine was degraded in these bacteria and induced agm atine deiminase, carbamoylputrescine hydrolase, putrescine oxidase, an d aminobutyraldehyde dehydrogenase. None of the enzymes was induced by L-arginine.