1h7h: Difference between revisions
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==Overview== | ==Overview== | ||
The enzyme CMP-Kdo synthetase (CKS) catalyzes the activation of the sugar, Kdo (2-keto-3-deoxy-manno-octonic acid) by forming a monophosphate, diester. CKS is a pharmaceutical target because CMP-Kdo is used in the, biosynthesis of lipopolysaccharides that are vital for Gram-negative, bacteria. We have refined the structure of the unligated capsule-specific, CKS from Escherichia coli at 1.8 A resolution (1 A=0.1 nm) and we have, established the structures of its complexes with the substrate CTP, with, CDP and CMP as well as with the product analog CMP-NeuAc (CMP-sialate) by, X-ray diffraction analyses at resolutions between 2.1 A and 2.5 A. The, N-terminal domains of the dimeric enzyme bind CTP in a peculiar, nucleotide-binding fold, whereas the C-terminal domains form the dimer, ... | The enzyme CMP-Kdo synthetase (CKS) catalyzes the activation of the sugar, Kdo (2-keto-3-deoxy-manno-octonic acid) by forming a monophosphate, diester. CKS is a pharmaceutical target because CMP-Kdo is used in the, biosynthesis of lipopolysaccharides that are vital for Gram-negative, bacteria. We have refined the structure of the unligated capsule-specific, CKS from Escherichia coli at 1.8 A resolution (1 A=0.1 nm) and we have, established the structures of its complexes with the substrate CTP, with, CDP and CMP as well as with the product analog CMP-NeuAc (CMP-sialate) by, X-ray diffraction analyses at resolutions between 2.1 A and 2.5 A. The, N-terminal domains of the dimeric enzyme bind CTP in a peculiar, nucleotide-binding fold, whereas the C-terminal domains form the dimer, interface. The observed binding geometries together with the amino acid, variabilities during evolution and the locations of a putative Mg(2+) and, of a very strongly bound water molecule suggest a pathway for the, catalysis. The N-terminal domain shows sequence homology with the, CMP-NeuAc synthetases. Moreover, the chain fold and the substrate-binding, position of CKS resemble those of other enzymes processing, nucleotide-sugars. | ||
==About this Structure== | ==About this Structure== | ||
1H7H is a | 1H7H is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with CDP as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/3-deoxy-manno-octulosonate_cytidylyltransferase 3-deoxy-manno-octulosonate cytidylyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.38 2.7.7.38] Structure known Active Sites: AC1 and AC2. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1H7H OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: sugar-activating enzymes]] | [[Category: sugar-activating enzymes]] | ||
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Revision as of 13:28, 5 November 2007
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THE STRUCTURE OF CMP:2-KETO-3-DEOXY-MANNO-OCTONIC ACID SYNTHETASE AND OF ITS COMPLEXES WITH SUBSTRATES AND SUBSTRATE ANALOGUES, CDP COMPLEX
OverviewOverview
The enzyme CMP-Kdo synthetase (CKS) catalyzes the activation of the sugar, Kdo (2-keto-3-deoxy-manno-octonic acid) by forming a monophosphate, diester. CKS is a pharmaceutical target because CMP-Kdo is used in the, biosynthesis of lipopolysaccharides that are vital for Gram-negative, bacteria. We have refined the structure of the unligated capsule-specific, CKS from Escherichia coli at 1.8 A resolution (1 A=0.1 nm) and we have, established the structures of its complexes with the substrate CTP, with, CDP and CMP as well as with the product analog CMP-NeuAc (CMP-sialate) by, X-ray diffraction analyses at resolutions between 2.1 A and 2.5 A. The, N-terminal domains of the dimeric enzyme bind CTP in a peculiar, nucleotide-binding fold, whereas the C-terminal domains form the dimer, interface. The observed binding geometries together with the amino acid, variabilities during evolution and the locations of a putative Mg(2+) and, of a very strongly bound water molecule suggest a pathway for the, catalysis. The N-terminal domain shows sequence homology with the, CMP-NeuAc synthetases. Moreover, the chain fold and the substrate-binding, position of CKS resemble those of other enzymes processing, nucleotide-sugars.
About this StructureAbout this Structure
1H7H is a Single protein structure of sequence from Escherichia coli with CDP as ligand. Active as 3-deoxy-manno-octulosonate cytidylyltransferase, with EC number 2.7.7.38 Structure known Active Sites: AC1 and AC2. Full crystallographic information is available from OCA.
ReferenceReference
The structure of CMP:2-keto-3-deoxy-manno-octonic acid synthetase and of its complexes with substrates and substrate analogs., Jelakovic S, Schulz GE, J Mol Biol. 2001 Sep 7;312(1):143-55. PMID:11545592
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