Sequential backbone resonance assignments of the E-coli dihydrofolate reductase Gly67Val mutant: folate complex

Occasionally, a mutation in an exposed loop region causes a significant change in protein function and/or stability. A single mutation Gly67Val of E. coli dihydrofolate reductase (DHFR) in the exposed CD loop is such an example. We have carried out the chemical shift assignments for H-N, N-H, C-alpha and C-beta atoms of the Gly67Val mutant of E. coli DHFR complexed with folate at pH 7.0, 35 A degrees C, and then evaluated the H-N, N-H, C-alpha and C-beta chemical shift changes caused by the mutation. The result indicates that, while the overall secondary structure remains the same, the single mutation Gly67Val causes site-specific conformational changes of the polypeptide backbone restricted around the adenosine-binding subdomain (residues 38-88) and not in the distant catalytic domain.