Glycoside hydrolase family 24

Phage lysozyme
lysozyme from bacteriophage lambda
Identifiers
Symbol	Phage_lysozyme
Pfam	PF00959
Pfam clan	CL0037
InterPro	IPR002196
SCOP	119l
SUPERFAMILY	119l
CAZy	GH24
CDD	cd00442
Available protein structures: Pfam structures PDB RCSB PDB; PDBe; PDBj PDBsum structure summary

In molecular biology, glycoside hydrolase family 24 is a family of glycoside hydrolases.

Glycoside hydrolases EC 3.2.1. are a widespread group of enzymes that hydrolyse the glycosidic bond between two or more carbohydrates, or between a carbohydrate and a non-carbohydrate moiety. A classification system for glycoside hydrolases, based on sequence similarity, has led to the definition of >100 different families.^[1][2][3] This classification is available on the CAZy(http://www.cazy.org/GH1.html) web site,^[4] and also discussed at CAZypedia, an online encyclopedia of carbohydrate active enzymes.^[5]

Glycoside hydrolase family 24 CAZY GH_24 comprises enzymes with only one known activity; lysozyme (EC 3.2.1.17). This family includes lambda phage lysozyme and Escherichia coli endolysin.^[6] Lysozyme helps to release mature phage particles from the cell wall by breaking down the peptidoglycan. The enzyme hydrolyses the 1,4-beta linkages between N-acetyl-D-glucosamine and N-acetylmuramic acid in peptidoglycan heteropolymers of prokaryotic cell walls. E. coli endolysin also functions in bacterial cell lysis and acts as a transglycosylase. The T4 lysozyme structure contains 2 domains, the interface between which forms the active-site cleft. The N-terminus of the 2 domains undergoes a 'hinge-bending' motion about an axis passing through the molecular waist.^[6][7] This mobility is thought to be important in allowing access of substrates to the enzyme active site.

References

1. Henrissat B, Callebaut I, Mornon JP, Fabrega S, Lehn P, Davies G (1995). "Conserved catalytic machinery and the prediction of a common fold for several families of glycosyl hydrolases". Proc. Natl. Acad. Sci. U.S.A. 92 (15): 7090–7094. doi:10.1073/pnas.92.15.7090. PMC 41477. PMID 7624375.
2. Henrissat B, Davies G (1995). "Structures and mechanisms of glycosyl hydrolases". Structure 3 (9): 853–859. doi:10.1016/S0969-2126(01)00220-9. PMID 8535779.
3. Bairoch, A. "Classification of glycosyl hydrolase families and index of glycosyl hydrolase entries in SWISS-PROT". 1999.
4. Henrissat, B. and Coutinho P.M. "Carbohydrate-Active Enzymes server". 1999.
5. CAZypedia, an online encyclopedia of carbohydrate-active enzymes.
6. Matthews BW, Weaver LH (1987). "Structure of bacteriophage T4 lysozyme refined at 1.7 A resolution". J. Mol. Biol. 193 (1): 189–199. doi:10.1016/0022-2836(87)90636-X. PMID 3586019.
7. Matthews BW, Faber HR (1990). "A mutant T4 lysozyme displays five different crystal conformations". Nature 348 (6298): 263–266. doi:10.1038/348263a0. PMID 2234094.