Abstract
Pseudomonas putida ATCC 12633 and some other fluorescent Pseudomonas strains utilized 1, 4-diguanidinobutane (arcaine) and its homologues with 3-7 methylene groups as sole nitrogen sources. The P. putida strain produced a novel enzyme which hydrolyzed 1, 4-diguanidinobutane to agmatine and urea; diguanidinobutane amidinohydrolase (EC class 3.5.3.) was proposed as the name for this enzyme. This enzyme hydrolyzed diguanidinoalkanes with 3-10 methylene groups; higher reaction rates were observed with 1, 4-diguanidinobutane, 1, 5-diguanidinopentane, and 1, 6-diguanidinohexane. The enzyme was also active toward agmatine, although the rate was below 1% of that toward 1, 4-diguanidinobutane, and it was suggested to catalyze the hydrolysis of the higher homologues of agmatine at higher rates.
The enzyme was induced by α, ω-diguanidinoalkanes with 3-7 methylene groups. The substrate specificities of the enzymes individually induced by the diguanidinoalkanes with 3-7 methylene groups were very close to each other. It was then concluded that only one enzyme was produced to catalyze the initial step of the degradation of the diguanidinoalkanes commonly.
