- DD-transpeptidase
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A transpeptidase (EC 3.4.16.4) is a bacterial enzyme that cross-links the peptidoglycan chains to form rigid cell walls. This enzyme is also known by several other names including DD-peptidase, DD-transpeptidase, D-alanyl-D-alanine carboxypeptidase and serine-type D-Ala-D-Ala carboxypeptidase.[1] In gram-positive bacteria, the peptidoglycan molecules are cross-linked by a pentapeptide bridge, whereas in gram-negative bacteria, the peptidoglycan molecules are directly covalently bound to each other.
The protein transpeptidase is also known as Novel penicillin-binding protein, which is necessary for cell wall peptidoglycan formation, and is inhibited by penicillin.
The antibiotic penicillin irreversibly binds to and inhibits the activity of the transpeptidase enzyme by forming a highly stable penicilloyl-enzyme intermediate. Because of the interaction between penicillin and transpeptidase, this enzyme is also known as "penicillin-binding protein."
References
- ^ "E.C.3.4.16.4 Serine-type D-Ala-D-Ala carboxypeptidase". Enzyme Structures Database. http://www.biochem.ucl.ac.uk/bsm/enzymes/ec3/ec04/ec16/ec0004/index.html. Retrieved February 26, 2006.
External links
- The MEROPS online database for peptidases and their inhibitors: S11.001
- EC 3.4.16.4
- MeSH Serine-Type+D-Ala-D-Ala+Carboxypeptidase
Hydrolase: proteases (EC 3.4) 3.4.11-19: Exopeptidase Dipeptidyl peptidase (Cathepsin C, Dipeptidyl peptidase-4) · Tripeptidyl peptidase (Tripeptidyl peptidase I, Tripeptidyl peptidase II)Serine type carboxypeptidases: Cathepsin A · DD-transpeptidaseOther/ungrouped3.4.21-24: Endopeptidase Serine proteases · Cysteine protease · Aspartic acid protease · Metalloendopeptidases
Other/ungrouped: Amyloid precursor protein secretase (Alpha secretase, Beta-secretase 1, Beta-secretase 2, Gamma secretase)3.4.99: Unknown B enzm: 1.1/2/3/4/5/6/7/8/10/11/13/14/15-18, 2.1/2/3/4/5/6/7/8, 2.7.10, 2.7.11-12, 3.1/2/3/4/5/6/7, 3.1.3.48, 3.4.21/22/23/24, 4.1/2/3/4/5/6, 5.1/2/3/4/99, 6.1-3/4/5-6 Categories:- EC 3.4.16
- Bacteria
- Microbiology
- Bacteria stubs
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