Stability of the heme environment of the nitric oxide synthase from Staphylococcus aureus in the absence of pterin cofactor.

ABSTRACT: We have used resonance Raman spectroscopy to probe the heme environment of a recently discovered NOS from the pathogenic bacterium Staphylococcus aureus, named SANOS. We detect two forms of the CO complex in the absence of L-arginine, with nu(Fe-CO) at 482 and 497 cm(-1) and nu(C-O) at 1949 and 1930 cm(-1), respectively. Similarly to mammalian NOS, the binding of L-arginine to SANOS caused the formation of a single CO complex with nu(Fe-CO) and nu(C-O) frequencies at 504 and 1,917 cm(-1), respectively, indicating that L-arginine induced an electrostatic/steric effect on the CO molecule. The addition of pterins to CO-bound SANOS modified the resonance Raman spectra only when they were added in combination with L-arginine. We found that (6R) 5,6,7,8 tetra-hydro-L-biopterin and tetrahydrofola

SUBMITTER: Chartier FJ 

PROVIDER: S-EPMC1304597 | biostudies-literature | 2004 Sep

REPOSITORIES: biostudies-literature