Crystal structure of a type II dehydroquinate dehydratase-like protein from Bifidobacterium longum.
Light, S.H., Krishna, S.N., Bergan, R.C., Lavie, A., Anderson, W.F.(2013) J Struct Funct Genomics 14: 25-30
- PubMed: 23539270 
- DOI: https://doi.org/10.1007/s10969-013-9149-7
- Primary Citation of Related Structures:  
3U80 - PubMed Abstract: 
Dehydroquinate dehydratase (DHQD) catalyzes the third step in the biosynthetic shikimate pathway. Here we identify a Bifidobacterium longum protein with high sequence homology to type II DHQDs but no detectable DHQD activity under standard assay conditions. A crystal structure reveals that the B. longum protein adopts a DHQD-like tertiary structure but a distinct quaternary state. Apparently forming a dimer, the B. longum protein lacks the active site aspartic acid contributed from a neighboring protomer in the type II DHQD dodecamer. Relating to the absence of protein-protein interactions established in the type II DHQD dodecameric assembly, substantial conformational changes distinguish the would-be active site of the B. longum protein. As B. longum possess no other genes with homology to known DHQDs, these findings imply a unique DHQD activity within B. longum.
Organizational Affiliation: 
Center for Structural Genomics of Infectious Diseases and Department of Molecular Pharmacology and Biological Chemistry, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.