Identification and characterization of nitric oxide synthase in Salmonella typhimurium.
The presence of the nitric oxide synthase (NOS) enzyme from Salmonella typhimurium (S. typhimurium) was identified by measuring radiolabeled L-[3H]citrulline and NO, and Western blot analysis. NOS was partially purified by both Mono Q ion exchange and Superose 12HR size exclusion column chromatography, sequentially. The molecular weight of NOS was estimated to be 93.3 kDa by Western blot analysis. The enzyme showed a significant dependency on the typical NOS cofactors; an apparent Km for L-arginine of 34.7 mM and maximum activity between 37 degrees C and 43 degrees C. The activity was inhibited by NOS inhibitors such as aminoguanidine and N(G),N(G)-dimethyl-L-arginine. Taken together, partially purified NOS in S. typhimurium is assumed to be a different isoform of mammalian NOSs.
Choi
D W
DW
College of Pharmacy, Sungkyunkwan University, Suwon city, Korea.
Oh
H Y
HY
Hong
S Y
SY
Han
J W
JW
Lee
H W
HW
D002956:Citrulline / Q000096:biosynthesis; D008970:Molecular Weight; D009569:Nitric Oxide / Q000096:biosynthesis; D019001:Nitric Oxide Synthase / Q000302:isolation & purification* / Q000378:metabolism; D012486:Salmonella typhimurium / Q000201:enzymology*
D002956:Citrulline; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase