Sandbox Reserved 477: Difference between revisions

Glyceraldehyde-3-Phosphate Dehydrogenase has two conserved domains in most isoforms. The NAD Binding Domain is an Alpha Beta 3-layer sandwich with a central beta sheet covered on both sides of the alpha helices. It includes amino acids 1-138 and 301-340 on chains O and Q. The second domain is composed of extensive antiparallel beta sheet regions. This domain also contains an S-shaped loop of polypeptide residues 178-201, which are in contact with NAD+ on the R axis. The S-loop also interacts with several amino acids across the P axis. The S-loop forms the core of the four subunits, and most of the residues are internal and essential for the interaction across the R axis. The Q-, R-, and P-axes make up the three orthogonal twofold symmetry axes of GAPDH, which relate the four subunits together.