Transpeptidase
Encyclopedia
A transpeptidase is a bacterial enzyme
that cross-link
s the peptidoglycan
chains to form rigid cell wall
s. 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. 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."
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
that cross-link
Cross-link
Cross-links are bonds that link one polymer chain to another. They can be covalent bonds or ionic bonds. "Polymer chains" can refer to synthetic polymers or natural polymers . When the term "cross-linking" is used in the synthetic polymer science field, it usually refers to the use of...
s the peptidoglycan
Peptidoglycan
Peptidoglycan, also known as murein, is a polymer consisting of sugars and amino acids that forms a mesh-like layer outside the plasma membrane of bacteria , forming the cell wall. The sugar component consists of alternating residues of β- linked N-acetylglucosamine and N-acetylmuramic acid...
chains to form rigid cell wall
Cell wall
The cell wall is the tough, usually flexible but sometimes fairly rigid layer that surrounds some types of cells. It is located outside the cell membrane and provides these cells with structural support and protection, and also acts as a filtering mechanism. A major function of the cell wall is to...
s. This enzyme is also known by several other names including DD-peptidase, DD-transpeptidase, D-alanyl-D-alanine carboxypeptidase
Carboxypeptidase
A carboxypeptidase is a protease enzyme that hydrolyzes the peptide bond of an amino acid residue at the carboxy-terminal end...
and serine-type D-Ala-D-Ala carboxypeptidase. 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
Antibiotic
An antibacterial is a compound or substance that kills or slows down the growth of bacteria.The term is often used synonymously with the term antibiotic; today, however, with increased knowledge of the causative agents of various infectious diseases, antibiotic has come to denote a broader range of...
penicillin
Penicillin
Penicillin is a group of antibiotics derived from Penicillium fungi. They include penicillin G, procaine penicillin, benzathine penicillin, and penicillin V....
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."
External links
- The MEROPSMeropsMerops may refer to:* Merops , a genus of bee-eaters.* MEROPS, an on-line database for peptidases.It may also refer to several figures from Greek mythology:* King of Ethiopia, husband of Clymene, who lay with Helios and bore Phaethon...
online database for peptidases and their inhibitors: S11.001