Reaction: [(1→2)-β-D-mannosyl]n + phosphate = [(1→2)-β-D-mannosyl]n-1 + α-D-mannose 1-phosphate
Systematic name: (1→2)-β-D-mannan:phosphate β-D-mannosyl transferase (configuration-inverting)
Comments: The enzyme, originally characterized from the thermophilic anaerobic bacterium Thermoanaerobacter sp. X514, catalyses a reversible reaction. In the synthetic direction it produces oligosaccharides with a degree of polymerization (DP) of 3, 4 and 5. The phosphorolysis reaction proceeds to completion, although activity is highest when the substrate has at least three residues. cf. EC 2.4.1.339, β-1,2-mannobiose phosphorylase.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Chiku, K., Nihira, T., Suzuki, E., Nishimoto, M., Kitaoka, M., Ohtsubo, K. and Nakai, H. Discovery of two β-1,2-mannoside phosphorylases showing different chain-length specificities from Thermoanaerobacter sp. X-514. PLoS One 9 (2014) e114882. [PMID: 25500577]