1mb9

[[Image:1mb9.gif|left|200px]]

|PDB= 1mb9 |SIZE=350|CAPTION= <scene name='initialview01'>1mb9</scene>, resolution 2.11&Aring;

|SITE=

|LIGAND= <scene name='pdbligand=AMP:ADENOSINE+MONOPHOSPHATE'>AMP</scene>, <scene name='pdbligand=ATP:ADENOSINE-5&#39;-TRIPHOSPHATE'>ATP</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=POP:PYROPHOSPHATE+2-'>POP</scene>

|ACTIVITY=

|GENE= 1901 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1901 Streptomyces clavuligerus])

|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1mb9 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1mb9 OCA], [http://www.ebi.ac.uk/pdbsum/1mb9 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1mb9 RCSB]</span>

 

 

 

==Overview==

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.

 

1MB9 is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Streptomyces_clavuligerus Streptomyces clavuligerus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1MB9 OCA].

 

==Reference==

The catalytic cycle of beta -lactam synthetase observed by x-ray crystallographic snapshots., Miller MT, Bachmann BO, Townsend CA, Rosenzweig AC, Proc Natl Acad Sci U S A. 2002 Nov 12;99(23):14752-7. Epub 2002 Oct 30. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/12409610 12409610]

[[Category: Single protein]]

[[Category: Bachmann, B O.]]

[[Category: Miller, M T.]]

[[Category: Rosenzweig, A C.]]

[[Category: Townsend, C A.]]