1skf
From Proteopedia
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==Overview== | ==Overview== | ||
| - | The serine DD-transpeptidase/penicillin-binding protein of Streptomyces, K15 catalyzes peptide bond formation in a way that mimics the, penicillin-sensitive peptide cross-linking reaction involved in bacterial, cell wall peptidoglycan assembly. The Streptomyces K15 enzyme is peculiar, in that it can be considered as an intermediate between classical, penicillin-binding proteins, for which benzylpenicillin is a very, efficient inactivator, and the resistant penicillin-binding proteins that, have a low penicillin affinity. With its moderate penicillin sensitivity, the Streptomyces K15 DD-transpeptidase would be helpful in the, understanding of the structure-activity relationship of this, penicillin-recognizing protein superfamily. The structure of the, Streptomyces K15 enzyme has been ... | + | The serine DD-transpeptidase/penicillin-binding protein of Streptomyces, K15 catalyzes peptide bond formation in a way that mimics the, penicillin-sensitive peptide cross-linking reaction involved in bacterial, cell wall peptidoglycan assembly. The Streptomyces K15 enzyme is peculiar, in that it can be considered as an intermediate between classical, penicillin-binding proteins, for which benzylpenicillin is a very, efficient inactivator, and the resistant penicillin-binding proteins that, have a low penicillin affinity. With its moderate penicillin sensitivity, the Streptomyces K15 DD-transpeptidase would be helpful in the, understanding of the structure-activity relationship of this, penicillin-recognizing protein superfamily. The structure of the, Streptomyces K15 enzyme has been determined by x-ray crystallography at, 2.0-A resolution and refined to an R-factor of 18.6%. The fold adopted by, this 262-amino acid polypeptide generates a two-domain structure that is, close to those of class A beta-lactamases. However, the Streptomyces K15, enzyme has two particular structural features. It lacks the amino-terminal, alpha-helix found in the other penicilloyl-serine transferases, and it, exhibits, at its surface, an additional four-stranded beta-sheet. These, two characteristics might serve to anchor the enzyme in the plasma, membrane. The overall topology of the catalytic pocket of the Streptomyces, K15 enzyme is also comparable to that of the class A beta-lactamases, except that the Omega-loop, which bears the essential catalytic Glu(166), residue in the class A beta-lactamases, is entirely modified. This loop, adopts a conformation similar to those found in the Streptomyces R61, DD-carboxypeptidase and class C beta-lactamases, with no equivalent acidic, residue. |
==About this Structure== | ==About this Structure== | ||
| - | 1SKF is a | + | 1SKF is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Streptomyces_sp. Streptomyces sp.]. Active as [http://en.wikipedia.org/wiki/Serine-type_D-Ala-D-Ala_carboxypeptidase Serine-type D-Ala-D-Ala carboxypeptidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.16.4 3.4.16.4] Structure known Active Site: ACT. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1SKF OCA]. |
==Reference== | ==Reference== | ||
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[[Category: serine peptidase]] | [[Category: serine peptidase]] | ||
| - | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Mon Nov 5 12:51:12 2007'' |
Revision as of 10:45, 5 November 2007
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CRYSTAL STRUCTURE OF THE STREPTOMYCES K15 DD-TRANSPEPTIDASE
Overview
The serine DD-transpeptidase/penicillin-binding protein of Streptomyces, K15 catalyzes peptide bond formation in a way that mimics the, penicillin-sensitive peptide cross-linking reaction involved in bacterial, cell wall peptidoglycan assembly. The Streptomyces K15 enzyme is peculiar, in that it can be considered as an intermediate between classical, penicillin-binding proteins, for which benzylpenicillin is a very, efficient inactivator, and the resistant penicillin-binding proteins that, have a low penicillin affinity. With its moderate penicillin sensitivity, the Streptomyces K15 DD-transpeptidase would be helpful in the, understanding of the structure-activity relationship of this, penicillin-recognizing protein superfamily. The structure of the, Streptomyces K15 enzyme has been determined by x-ray crystallography at, 2.0-A resolution and refined to an R-factor of 18.6%. The fold adopted by, this 262-amino acid polypeptide generates a two-domain structure that is, close to those of class A beta-lactamases. However, the Streptomyces K15, enzyme has two particular structural features. It lacks the amino-terminal, alpha-helix found in the other penicilloyl-serine transferases, and it, exhibits, at its surface, an additional four-stranded beta-sheet. These, two characteristics might serve to anchor the enzyme in the plasma, membrane. The overall topology of the catalytic pocket of the Streptomyces, K15 enzyme is also comparable to that of the class A beta-lactamases, except that the Omega-loop, which bears the essential catalytic Glu(166), residue in the class A beta-lactamases, is entirely modified. This loop, adopts a conformation similar to those found in the Streptomyces R61, DD-carboxypeptidase and class C beta-lactamases, with no equivalent acidic, residue.
About this Structure
1SKF is a Single protein structure of sequence from Streptomyces sp.. Active as Serine-type D-Ala-D-Ala carboxypeptidase, with EC number 3.4.16.4 Structure known Active Site: ACT. Full crystallographic information is available from OCA.
Reference
The crystal structure of a penicilloyl-serine transferase of intermediate penicillin sensitivity. The DD-transpeptidase of streptomyces K15., Fonze E, Vermeire M, Nguyen-Disteche M, Brasseur R, Charlier P, J Biol Chem. 1999 Jul 30;274(31):21853-60. PMID:10419503
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