2 * 80000, fusion enzyme consisting of UDP-galactose 4-epimerase and galactose-1-phosphate uridylyltransferase with an intervening Ala3 linker exist as monomeric, dimeric and tetrameric form. The monomeric form has low epimerase activity, SDS-PAGE
wild-type protein and all the mutants (N34S, G90E, V94M, D103G, L183P, K257R, L313M, G319E and R335H) are able to form dimers. In all cases, especially with the mutant proteins, some higher molecular mass species are also observed
The resulting model is composed of four subunits forming two physiological dimers (subunits AB and CD). Subunit A comprises residues -1150, 157237 and 249381, subunit B residues -1150, 158235 and 249381, subunit C residues -1152, 158237 and 248381 and subunit D residues -1150, 157235 and 249381.The -1 refers to a serine residue which precedes the initiating methionine and is an artifact of the expression plasmid that generates an N-terminal extension. There are several missing residues which belong to flexible surface loops. Each active site is occupied by well ordered NAD+ and UDP-FGal.
2 * 80000, fusion enzyme consisting of UDP-galactose 4-epimerase and galactose-1-phosphate uridylyltransferase with an intervening Ala3 linker exist as monomeric, dimeric and tetrameric form. The monomeric form has low epimerase activity, SDS-PAGE
4 * 80000, fusion enzyme consisting of UDP-galactose 4-epimerase and galactose-1-phosphate uridylyltransferase with an intervening Ala3 linker exist as monomeric, dimeric and tetrameric form. The monomeric form has low epimerase activity, SDS-PAGE
the enzyme has an N-terminal nucleotide binding domain and a smaller C-terminal domain that is responsible for the correct positioning of its substrate, a UDP-sugar. The N-terminal domain comprises seven parallel beta-strands that are flanked on both sides by alpha-helices and shape the Rossmann fold. Two paired Rossmann folds tightly bind one NAD+ cofactor per subunit
sequence comparisons and structure homology modeling, overview. The enzyme's catalytic triad contains a threonine residue (Thr117) instead of the usual serine