Reaction: Exotype eliminative cleavage of α-L-rhamnopyranosyl-(1→4)-α-D-galactopyranosyluronic acid bonds of rhamnogalacturonan I oligosacharides containing α-L-rhamnopyranose at the reducing end and 4-deoxy-4,5-unsaturated D-galactopyranosyluronic acid at the nonreducing end. The products are the disaccharide 2-O-(4-deoxy-β-L-threo-hex-4-enopyranuronosyl)-α-L-rhamnopyranose and the shortened rhamnogalacturonan oligosaccharide containing one 4-deoxy-4,5-unsaturated D-galactopyranosyluronic acid at the non-reducing end.
For diagram of reaction click here.
Glossary: 6-deoxy-2-O-(4-deoxy-β-L-threo-hex-4-enopyranuronosyl)-α-L-mannopyranose =
2-O-(4-deoxy-β-L-threo-hex-4-enopyranuronosyl)-α-L-rhamnopyranose
Other name(s): YesX
Systematic name: α-L-rhamnopyranosyl-(1→4)-α-D-galactopyranosyluronate exolyase
Comments: The enzyme is part of the degradation system for rhamnogalacturonan I in Bacillus subtilis strain 168.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:
References:
1. Ochiai, A., Itoh, T., Mikami, B., Hashimoto, W. and Murata, K. Structural determinants responsible for substrate recognition and mode of action in family 11 polysaccharide lyases. J. Biol. Chem. 284 (2009) 10181-10189. [PMID: 19193638]
2. Ochiai, A., Itoh, T., Kawamata, A., Hashimoto, W. and Murata, K. Plant cell wall degradation by saprophytic Bacillus subtilis strains: gene clusters responsible for rhamnogalacturonan depolymerization. Appl. Environ. Microbiol. 73 (2007) 3803-3813. [PMID: 17449691]