Gamma-glutamyl-gamma-aminobutyrate hydrolase in the putrescine utilization pathway of Escherichia coli K-12.
gamma-Glutamyl-gamma-aminobutyrate hydrolase (PuuD) was purified and the properties of the enzyme were characterized. The active center of PuuD was identified as Cys-114 by site-directed mutagenesis. The expression of PuuD was induced by putrescine and O2 (substrates of the Puu pathway), while the addition of succinate or NH4Cl (products of the Puu pathway) to the medium reduced the expression of PuuD. The findings that the puuD-deficient strain accumulated gamma-glutamyl-gamma-aminobutyrate (gamma-Glu-GABA) and could not grow on putrescine as a sole nitrogen source indicate that PuuD is physiologically important as a gamma-Glu-GABA hydrolase.
Kurihara
Shin
S
Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Kyoto, Japan.
Oda
Shinpei
S
Kumagai
Hidehiko
H
Suzuki
Hideyuki
H
D000445:Aldehyde Oxidoreductases / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D000643:Ammonium Chloride / Q000494:pharmacology; D001665:Binding Sites / Q000235:genetics; D004151:Dipeptides / Q000378:metabolism; D048168:Escherichia coli K12 / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D016297:Mutagenesis, Site-Directed; D009584:Nitrogen / Q000378:metabolism; D010100:Oxygen / Q000494:pharmacology; D011700:Putrescine / Q000378:metabolism* / Q000494:pharmacology; D019802:Succinic Acid / Q000494:pharmacology
D004151:Dipeptides; D000643:Ammonium Chloride; C076487:gamma glutamyl GABA; D019802:Succinic Acid; D000445:Aldehyde Oxidoreductases; C019679:aminobutyraldehyde dehydrogenase; D009584:Nitrogen; D010100:Oxygen; D011700:Putrescine