Premium
Catalase activity of oxygenase domain of rat neuronal nitric oxide synthase. Evidence for product formation from L ‐arginine
Author(s) -
Adhikari Sanjay,
Ray Soma,
Gachhui Ratan
Publication year - 2000
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/s0014-5793(00)01616-1
Subject(s) - tetrahydrobiopterin , nitric oxide , nitric oxide synthase , heme oxygenase , chemistry , arginine , oxygenase , heme , biochemistry , catalase , nos1 , atp synthase , enzyme , amino acid , organic chemistry
Nitric oxide synthases (NOSs) catalyze the formation of nitric oxide from L ‐arginine. We purified the heme containing, tetrahydrobiopterin‐free, oxygenase domain of rat neuronal nitric oxide synthase (nNOSox) overexpressed in Escherichia coli . We found catalase activity in nNOSox. This is significant because H 2 O 2 may also be a product of nitric oxide synthases. We found H 2 O 2 assisted product formation from N ‐hydroxy‐ L ‐arginine and even from L ‐arginine both in the presence and in absence of tetrahydrobiopterin. We propose how heme moiety of the oxygenase domain alone is sufficient to carry out both steps of the NOS catalysis.