Guanidinobutyrase for L-arginine degradation in Brevibacterium helvolum

• Published in: Bioscience, biotechnology, and biochemistry Vol. 56; no. 5; pp. 773 - 777
• Main Authors: Yorifuji, T. (Shinshu Univ., Matsumoto, Nagano (Japan)), Shimizu, E, Hirata, H, Imada, K, Katsumi, T, Sawamura, S
• Format: Journal Article
• Language: English
• Published: Tokyo Taylor & Francis 1992; Japan Society for Bioscience Biotechnology and Agrochemistry; Oxford University Press
• Subjects: Analytical, structural and metabolic biochemistry; ARGININA; ARGININE; Biological and medical sciences; BREVIBACTERIUM; Brevibacterium helvolum; DEGRADACION; DEGRADATION; Enzymes and enzyme inhibitors; Fundamental and applied biological sciences. Psychology; HIDROLASAS; HYDROLASE; HYDROLASES; Purification; Enzyme; Brevibacteriaceae; Molecular weight; Thermal stability; Characterization; Proteins; Brevibacterium helvolum; Guanidinobutyrase; Enzymatic activity; Substrate specificity; Bacteria; Actinomycetes; Inhibition; Structure; Physicochemical properties
• ISSN: 0916-8451; 1347-6947
• DOI: 10.1271/bbb.56.773

Guanidinobutyrase (guanidinobutyrate amidinohydrolase, EC. 3.5.3.7) catalyzing the third step of the arginine oxygenase pathway in Brevibacterium helvolum IFO 12073 (ATCC 11822) was purified to homogeneity and characterized. The enzyme had a molecular weight of 190,000 and was composed of four apparently identical subunits with a molecular weight of 45,000. The E(1%) value at 280 nm of the enzyme protein was 2.4. The enzyme contained 0.5 mol of firmly bound Zn 2+ per mol of subunit. The enzyme was highly specific for 4-guanidinobutyrate, but had a weak activity toward L- and D-arginine. The Michaelis constant (K m ) for 4-guanidinobutyrate was 2.9 mM. The optimum pH was 9.0. Strong mixed type inhibition was observed with thioglycolate and several other thiol compounds. These properties were compared with those of the enzyme of fluorescent Pseudomonas and discussed.