Function
Laminarase (LAM) or endo-1,3-beta-glucanase family GH16 or glycoside hydrolase family 16 degrades 1,3-beta glycosyl linkages of beta-glucan via the hydrolysis of glycosidic bonds[1].
Relevance
LAM cleaves laminarin which is an abundant polysaccharide found in alga which serves as carbon storage for nutrition of microbes. The depolymerization of laminarin initiates remineralization which is a key process in ocean biogeochemical cycles[2].
Structural highlights
The 3D structure of laminarase complexed with cellotriose shows the enzyme having a β-jellyroll fold typical to the GH16 family. The oligosaccharide is bound at the concave face of the molecule with 2 Glu residues defined as the nucleophile and acid/base residues in the active site. The ligand is coordinated via H-bonds and CH-π interactions[3].
3D structures of laminarase
Laminarase 3D structures
- ↑ Qin HM, Miyakawa T, Inoue A, Nakamura A, Nishiyama R, Ojima T, Tanokura M. Laminarinase from Flavobacterium sp. reveals the structural basis of thermostability and substrate specificity. Sci Rep. 2017 Sep 12;7(1):11425. doi: 10.1038/s41598-017-11542-0. PMID:28900273 doi:https://dx.doi.org/10.1038/s41598-017-11542-0
- ↑ Yang J, Xu Y, Miyakawa T, Long L, Tanokura M. Molecular basis for substrate recognition and catalysis by a marine bacterial laminarinase. Appl Environ Microbiol. 2020 Sep 11. pii: AEM.01796-20. doi:, 10.1128/AEM.01796-20. PMID:32917756 doi:https://dx.doi.org/10.1128/AEM.01796-20
- ↑ Liberato MV, Teixeira Prates E, Goncalves TA, Bernardes A, Vilela N, Fattori J, Ematsu GC, Chinaglia M, Machi Gomes ER, Migliorini Figueira AC, Damasio A, Polikarpov I, Skaf MS, Squina FM. Insights into the dual cleavage activity of the GH16 laminarinase enzyme class on beta-1,3 and beta-1,4 glycosidic bonds. J Biol Chem. 2021 Jan-Jun;296:100385. doi: 10.1016/j.jbc.2021.100385. Epub 2021, Feb 5. PMID:33556371 doi:https://dx.doi.org/10.1016/j.jbc.2021.100385
