PMID- 20806221
OWN - NLM
STAT- MEDLINE
DCOM- 20110215
LR  - 20101109
IS  - 1097-0134 (Electronic)
IS  - 0887-3585 (Linking)
VI  - 78
IP  - 16
DP  - 2010 Dec
TI  - Potential anti-bacterial drug target: structural characterization of 
      3,4-dihydroxy-2-butanone-4-phosphate synthase from Salmonella typhimurium LT2.
PG  - 3292-303
LID - 10.1002/prot.22837 [doi]
AB  - 3,4-Dihydroxy-2-butanone-4-phosphate synthase (DHBPS) encoded by ribB gene is one 
      of the first enzymes in riboflavin biosynthesis pathway and catalyzes the 
      conversion of ribulose-5-phosphate (Ru5P) to 3,4-dihydroxy-2-butanone-4-phosphate 
      and formate. DHBPS is an attractive target for developing anti-bacterial drugs as 
      this enzyme is essential for pathogens, but absent in humans. The recombinant 
      DHBPS enzyme of Salmonella requires magnesium ion for its activity and catalyzes 
      the formation of 3,4-dihydroxy-2-butanone-4-phosphate from Ru5P at a rate of 199 
      nmol min(-1) mg(-1) with K(m) value of 116 muM at 37 degrees C. Further, we have 
      determined the crystal structures of Salmonella DHBPS in complex with sulfate, 
      Ru5P and sulfate-zinc ion at a resolution of 2.80, 2.52, and 1.86 A, 
      respectively. Analysis of these crystal structures reveals that the acidic loop 
      (residues 34-39) responsible for the acid-base catalysis is disordered in the 
      absence of substrate or metal ion at the active site. Upon binding either 
      substrate or sulfate and metal ions, the acidic loop becomes stabilized, adopts a 
      closed conformation and interacts with the substrate. Our structure for the first 
      time reveals that binding of substrate Ru5P alone is sufficient for the 
      stabilization of the acidic active site loop into a closed conformation. In 
      addition, the Glu38 residue from the acidic active site loop undergoes a 
      conformational change upon Ru5P binding, which helps in positioning the second 
      metal ion that stabilizes the Ru5P and the reaction intermediates. This is the 
      first structural report of DHBPS in complex with either substrate or metal ion 
      from any eubacteria.
CI  - Copyright (c) 2010 Wiley-Liss, Inc.
FAU - Kumar, Pankaj
AU  - Kumar P
AD  - Institute of Microbial Technology, Council of Scientific and Industrial Research 
      (CSIR), Sector 39-A, Chandigarh 160 036, India.
FAU - Singh, Mirage
AU  - Singh M
FAU - Gautam, Ruchi
AU  - Gautam R
FAU - Karthikeyan, Subramanian
AU  - Karthikeyan S
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Proteins
JT  - Proteins
JID - 8700181
RN  - 0 (Anti-Bacterial Agents)
RN  - 0 (Metals)
RN  - 0 (Ribulosephosphates)
RN  - 0 (Sulfates)
RN  - 4151-19-3 (ribulose 5-phosphate)
RN  - EC 5.4.- (Intramolecular Transferases)
RN  - EC 5.4.- (L-3,4-dihydroxy-2-butanone-4-phosphate synthase)
SB  - IM
MH  - Anti-Bacterial Agents/*pharmacology
MH  - Biocatalysis/drug effects
MH  - Catalytic Domain
MH  - Cloning, Molecular
MH  - Crystallography, X-Ray
MH  - Enzyme Assays
MH  - Intramolecular Transferases/*antagonists & inhibitors/*chemistry/isolation & 
      purification
MH  - Kinetics
MH  - Metals/metabolism
MH  - Models, Molecular
MH  - Ribulosephosphates/metabolism
MH  - Salmonella typhimurium/drug effects/*enzymology
MH  - Substrate Specificity/drug effects
MH  - Sulfates/metabolism
EDAT- 2010/09/02 06:00
MHDA- 2011/02/16 06:00
CRDT- 2010/09/01 06:00
PHST- 2010/09/01 06:00 [entrez]
PHST- 2010/09/02 06:00 [pubmed]
PHST- 2011/02/16 06:00 [medline]
AID - 10.1002/prot.22837 [doi]
PST - ppublish
SO  - Proteins. 2010 Dec;78(16):3292-303. doi: 10.1002/prot.22837.