PMID- 12409610
OWN - NLM
STAT- MEDLINE
DCOM- 20030115
LR  - 20170219
IS  - 0027-8424 (Print)
IS  - 0027-8424 (Linking)
VI  - 99
IP  - 23
DP  - 2002 Nov 12
TI  - The catalytic cycle of beta -lactam synthetase observed by x-ray crystallographic
      snapshots.
PG  - 14752-7
AB  - The catalytic cycle of the ATP/Mg(2+)-dependent enzyme beta-lactam synthetase
      (beta-LS) from Streptomyces clavuligerus has been observed through a series of
      x-ray crystallographic snapshots. Chemistry is initiated by the ordered binding
      of ATP/Mg(2+) and N(2)-(carboxyethyl)-l-arginine (CEA) to the apoenzyme. The apo 
      and ATP/Mg(2+) structures described here, along with the previously described
      CEA.alpha,beta-methyleneadenosine 5'-triphosphate (CEA.AMP-CPP)/Mg(2+) structure,
      illuminate changes in active site geometry that favor adenylation. In addition,
      an acyladenylate intermediate has been trapped. The substrate analog
      N(2)-(carboxymethyl)-l-arginine (CMA) was adenylated by ATP in the crystal and
      represents a close structural analog of the previously proposed CEA-adenylate
      intermediate. Finally, the structure of the ternary product complex
      deoxyguanidinoproclavaminic acid (DGPC).AMP/PP(i)/Mg(2+) has been determined. The
      CMA-AMP/PP(i)/Mg(2+) and DGPC.AMP/PP(i)/Mg(2+) structures reveal interactions in 
      the active site that facilitate beta-lactam formation. All of the ATP-bound
      structures differ from the previously described CEA.AMP-CPP/Mg(2+) structure in
      that two Mg(2+) ions are found in the active sites. These Mg(2+) ions play
      critical roles in both the adenylation and beta-lactamization reactions.
FAU - Miller, Matthew T
AU  - Miller MT
AD  - Department of Biochemistry, Northwestern University, Evanston, IL 60208, USA.
FAU - Bachmann, Brian O
AU  - Bachmann BO
FAU - Townsend, Craig A
AU  - Townsend CA
FAU - Rosenzweig, Amy C
AU  - Rosenzweig AC
LA  - eng
GR  - R56 AI014937/AI/NIAID NIH HHS/United States
GR  - R01 AI014937/AI/NIAID NIH HHS/United States
GR  - T32 GM008061/GM/NIGMS NIH HHS/United States
GR  - GM008061/GM/NIGMS NIH HHS/United States
GR  - R37 AI014937/AI/NIAID NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
DEP - 20021030
PL  - United States
TA  - Proc Natl Acad Sci U S A
JT  - Proceedings of the National Academy of Sciences of the United States of America
JID - 7505876
RN  - 8L70Q75FXE (Adenosine Triphosphate)
RN  - EC 3.5.- (Amidohydrolases)
RN  - EC 3.5.2.- (beta-lactam synthetase)
RN  - I38ZP9992A (Magnesium)
SB  - IM
MH  - Adenosine Triphosphate/metabolism
MH  - Amidohydrolases/*chemistry/*metabolism
MH  - Binding Sites
MH  - Catalysis
MH  - Crystallography, X-Ray
MH  - Hydrogen Bonding
MH  - Magnesium/pharmacology
MH  - Models, Molecular
MH  - Protein Conformation
MH  - Streptomyces/*enzymology
PMC - PMC137491
OID - NLM: PMC137491
EDAT- 2002/11/01 04:00
MHDA- 2003/01/16 04:00
CRDT- 2002/11/01 04:00
PHST- 2002/11/01 04:00 [pubmed]
PHST- 2003/01/16 04:00 [medline]
PHST- 2002/11/01 04:00 [entrez]
AID - 10.1073/pnas.232361199 [doi]
AID - 232361199 [pii]
PST - ppublish
SO  - Proc Natl Acad Sci U S A. 2002 Nov 12;99(23):14752-7. doi:
      10.1073/pnas.232361199. Epub 2002 Oct 30.