Download MendeleyThe first structure of UDP-glucose dehydrogenase reveals the catalytic residues necessary for the two-fold oxidation.
Campbell, R.E., Mosimann, S.C., van De Rijn, I., Tanner, M.E., Strynadka, N.C.(2000) Biochemistry 39: 7012-7023
- PubMed: 10841783
- Primary Citation of Related Structures:
1DLI, 1DLJ - PubMed Abstract:
Bacterial UDP-glucose dehydrogenase (UDPGlcDH) is essential for formation of the antiphagocytic capsule that protects many virulent bacteria such as Streptococcus pyogenes andStreptococcus pneumoniae type 3 from the host's immune system. We have determined the X-ray structures of both native and Cys260Ser UDPGlcDH from S. pyogenes (74% similarity to S. pneumoniae) in ternary complexes with UDP-xylose/NAD(+) and UDP-glucuronic acid/NAD(H), respectively. The 402 residue homodimeric UDPGlcDH is composed of an N-terminal NAD(+) dinucleotide binding domain and a C-terminal UDP-sugar binding domain connected by a long (48 A) central alpha-helix. The first 290 residues of UDPGlcDH share structural homology with 6-phosphogluconate dehydrogenase, including conservation of an active site lysine and asparagine that are implicated in the enzyme mechanism. Also proposed to participate in the catalytic mechanism are a threonine and a glutamate that hydrogen bond to a conserved active site water molecule suitably positioned for general acid/base catalysis.
Organizational Affiliation:
Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3.
