Related Research Articles
Peptidoglycan or murein is a unique large macromolecule, a polysaccharide, consisting of sugars and amino acids that forms a mesh-like peptidoglycan layer (sacculus) that surrounds the bacterial cytoplasmic membrane. The sugar component consists of alternating residues of β-(1,4) linked N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM). Attached to the N-acetylmuramic acid is an oligopeptide chain made of three to five amino acids. The peptide chain can be cross-linked to the peptide chain of another strand forming the 3D mesh-like layer. Peptidoglycan serves a structural role in the bacterial cell wall, giving structural strength, as well as counteracting the osmotic pressure of the cytoplasm. This repetitive linking results in a dense peptidoglycan layer which is critical for maintaining cell form and withstanding high osmotic pressures, and it is regularly replaced by peptidoglycan production. Peptidoglycan hydrolysis and synthesis are two processes that must occur in order for cells to grow and multiply, a technique carried out in three stages: clipping of current material, insertion of new material, and re-crosslinking of existing material to new material.
Uridine diphosphate N-acetylglucosamine or UDP-GlcNAc is a nucleotide sugar and a coenzyme in metabolism. It is used by glycosyltransferases to transfer N-acetylglucosamine residues to substrates. D-Glucosamine is made naturally in the form of glucosamine-6-phosphate, and is the biochemical precursor of all nitrogen-containing sugars. To be specific, glucosamine-6-phosphate is synthesized from fructose 6-phosphate and glutamine as the first step of the hexosamine biosynthesis pathway. The end-product of this pathway is UDP-GlcNAc, which is then used for making glycosaminoglycans, proteoglycans, and glycolipids.
In enzymology, a D-aspartate ligase is an enzyme that catalyzes the chemical reaction
In enzymology, a UDP-N-acetylmuramate—L-alanine ligase is an enzyme that catalyzes the chemical reaction
In enzymology, a UDP-N-acetylmuramoyl-L-alanyl-D-glutamate—L-lysine ligase is an enzyme that catalyzes the chemical reaction
In enzymology, a UDP-N-acetylmuramoyl-tripeptide—D-alanyl-D-alanine ligase is an enzyme that catalyzes the chemical reaction
In enzymology, a N-acetylglucosaminylphosphatidylinositol deacetylase (EC 3.5.1.89) is an enzyme that catalyzes the chemical reaction
In enzymology, a glycoprotein 2-beta-D-xylosyltransferase (EC 2.4.2.38) is an enzyme that catalyzes the chemical reaction
In enzymology, a glycoprotein 3-alpha-L-fucosyltransferase (EC 2.4.1.214) is an enzyme that catalyzes the chemical reaction
In enzymology, a glycoprotein 6-alpha-L-fucosyltransferase (EC 2.4.1.68) is an enzyme that catalyzes the chemical reaction
In enzymology, a N-acetyllactosaminide 3-alpha-galactosyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a N-acetyllactosaminide beta-1,3-N-acetylglucosaminyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a N-acetyllactosaminide beta-1,6-N-acetylglucosaminyl-transferase is an enzyme that catalyzes the chemical reaction
In enzymology, a [Skp1-protein]-hydroxyproline N-acetylglucosaminyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, an undecaprenyldiphospho-muramoylpentapeptide beta-N-acetylglucosaminyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, an UDP-N-acetylglucosamine—dolichyl-phosphate N-acetylglucosaminephosphotransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a phospho-N-acetylmuramoyl-pentapeptide-transferase is an enzyme that catalyzes the chemical reaction
The bacterial cell wall provides strength and rigidity to counteract internal osmotic pressure, and protection against the environment. The peptidoglycan layer gives the cell wall its strength, and helps maintain the overall shape of the cell. The basic peptidoglycan structure of both Gram-positive and Gram-negative bacteria comprises a sheet of glycan chains connected by short cross-linking polypeptides. Biosynthesis of peptidoglycan is a multi-step process comprising three main stages:
- formation of UDP-N-acetylmuramic acid (UDPMurNAc) from N-acetylglucosamine (GlcNAc).
- addition of a short polypeptide chain to the UDPMurNAc.
- addition of a second GlcNAc to the disaccharide-pentapeptide building block and transport of this unit through the cytoplasmic membrane and incorporation into the growing peptidoglycan layer.
N-acetyl-beta-glucosaminyl-glycoprotein 4-beta-N-acetylgalactosaminyltransferase is an enzyme with systematic name UDP-N-acetyl-D-galactosamine:N-acetyl-beta-D-glucosaminyl-group 4-beta-N-acetylgalactosaminyltransferase. This enzyme catalyses the following chemical reaction
UDP-N-acetylglucosamine—undecaprenyl-phosphate N-acetylglucosaminephosphotransferase is an enzyme with systematic name UDP-N-acetyl-alpha-D-glucosamine:ditrans,octacis-undecaprenyl phosphate N-acetyl-alpha-D-glucosaminephosphotransferase. This enzyme catalyses the following chemical reaction
References
- ↑ Mesleh MF, Rajaratnam P, Conrad M, Chandrasekaran V, Liu CM, Pandya BA, et al. (February 2016). "Targeting Bacterial Cell Wall Peptidoglycan Synthesis by Inhibition of Glycosyltransferase Activity". Chemical Biology & Drug Design. 87 (2): 190–199. doi:10.1111/cbdd.12662. PMID 26358369.
- ↑ Yuan Y, Barrett D, Zhang Y, Kahne D, Sliz P, Walker S (March 2007). "Crystal structure of a peptidoglycan glycosyltransferase suggests a model for processive glycan chain synthesis". Proceedings of the National Academy of Sciences of the United States of America. 104 (13): 5348–5353. doi:10.1073/pnas.0701160104. PMC 1817829 . PMID 17360321.
- ↑ "Information on EC 2.4.1.129 - peptidoglycan glycosyltransferase - BRENDA Enzyme Database". www.brenda-enzymes.org. Retrieved 2022-05-13.
