CtXR (xylose reductase from the yeast Candida tenuis; AKR2B5) can utilize NADPH or NADH as co-substrate for the reduction of D-xylose into xylitol, NADPH being preferred approx. 33-fold. X-ray structures of CtXR bound to NADP+ and NAD+ have revealed two different protein conformations capable of accommodating the presence or absence of the coenzyme 2'-phosphate group. Here we have used site-dir...

The cofactor requirements of macrophage nitric oxide (NO.) synthase suggest involvement of an NADPH-dependent flavoprotein. This prompted us to test the effect of the flavoprotein inhibitors diphenyleneiodonium (DPI), di-2-thienyliodonium (DTI), and iodoniumdiphenyl (ID) on the NO. synthases of macrophages and endothelium. DPI, DTI, and ID completely inhibited NO. synthesis by mouse macrophages...

A computational strategy for homology modeling, using several protein structures comparison, is described. This strategy implies a formalized definition of structural blocks common to several protein structures, a new program to compare these structures simultaneously, and the use of consensus matrices to improve sequence alignment between the structurally known and target proteins. Applying th...

The association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and colorectal cancer (CRC) susceptibility has been researched in numerous studies. However, the results of these studies were controversial. Therefore, the objective of this meta-analysis was to offer a more convincible conclusion about such association with more included studies. Eligible studies published ...

Rat liver NAD kinase (ATP : NAD 2’-phosphotransferase, EC 2.7.1.23) was purified about 70-fold. The MichaelisMenten constants (Km) for NAD and ATP were 8 x 10e4 M and 2 x low3 M, respectively. NAD kinase activity was markedly inhibited by NADH and also NADPH. The Ki of NADH was approximately 1 X 10q4 M, and that of NADPH was approximately 5 X 10M5 M. Both inhibitions were competitive with NAD, ...

Superoxide production by stimulated neutrophils and by preparations of NADPH oxidase has consistently been measured by an indirect method utilising the reduction of cytochrome c by superoxide radicals [4]. This reduction is inhibited by superoxide dismutase. EPR spectroscopy using the technique of spin trapping has been used to identify superoxide radicals formed by photo-irradiated spinach chl...

By the use of ferritin-conjugated antibody (conjugate) indirect immunoelectron microscopy, NADPH-cytochrome c reductase was localized on rat liver microsomes. Most microsomes in the sections had from 1 to 12 conjugates on their outer surfaces. Among the conjugates, 83% was estimated to bind to NADPH-cytochrome c reductase at a molecular ratio of 1:1, 12% at the ratio of 2:1, and 5% at the ratio...