What does XR stand for?
XR stands for xylose reductase
This definition appears rarely
See other definitions of XR
Samples in periodicals archive:
D-xylose reductase (EC 1. 1. 1. 307, XylR, XyrA, msXR, dsXR, monospecific xylose reductase, dual specific xylose reductase, NAD(P)H-dependent xylose reductase, xylose reductase) is an enzyme with system name xylitol:NAD(P)+ oxidoreductase.
XR,Xylose Reductase,xylose reductases Xylose Reductase - XR.
This pathway is also called the “Xylose Reductase-Xylitol Dehydrogenase” or XR-XDH pathway. Xylose reductase (XR) and xylitol dehydrogenase (XDH) are the first two enzymes in this pathway. XR is reducing D-xylose to xylitol using NADH or NADPH. Xylitol is then oxidized to D-xylulose by XDH, using the cofactor NAD. In the last step D-xylulose is phosphorylated by an ATP utilising kinase, XK, to result in D-xylulose-5-phosphate which is an intermediate of the pentose phosphate pathway.
XR encoded by the C. parapsilosis XYL1 gene is the first XR enzyme reported to prefer NADH . The C. parapsilosis XR carries an arginine instead of a lysine in the Ile-Pro-Lys-Ser motif that is conserved among NADPH-dependent xylose reductases . The replacement of the lysine by an arginine in the K270R mutant of P. stipitis XR was made to mimic the C. parapsilosis XR. Strain TMB 3200 expressing the K270R mutant of P.
Effects of the expression mode of the xylose reductase gene (XYL1) on xylitol production in recombinant Saccharomyces cerevisiae strains were investigated in batch and fed-batch cultures. The gene coding for xylose reductase (XR) was introduced into S. cerevisiae in two different ways: by using a d-integration vector for chromosome-integration and a YRp-based episomal plasmid vector. The two expression systems showed the different pattern of xylitol production in a glucose-limited fed-batch culture as opposed to the similar profile in a batch culture.