Reaction: an α-L-rhamnose-(1→4)-β-D-glucuronide = α-L-rhamnopyranose + a 4-deoxy-α-L-threo-hex-4-enopyranuronoside
Other name(s): L-rhamnose-α-1,4-D-glucuronate lyase; FoRham (gene name)
Systematic name: α-L-rhamnosyl-(1→4)-β-D-glucuronate lyase
Comments: The enzyme, characterized from the phytopathogenic fungus Fusarium oxysporum, removes the rhamnosyl residue from α-L-rhamnosyl-(1→4)-β-D-glucuronate or from oligosaccharides that contain this motif at the non-reducing end, leaving an unsaturated glucuronate residue. Among its natural substrates is the type II arabinogalactan component of gum arabic.
References:
1. Kondo, T., Kichijo, M., Maruta, A., Nakaya, M., Takenaka, S., Arakawa, T., Fushinobu, S. and Sakamoto, T. Structural and functional analysis of gum arabic L-rhamnose-α-1,4-D-glucuronate lyase establishes a novel polysaccharide lyase family. J. Biol. Chem. 297 (2021) 101001. [PMID: 34303708]