Reaction: Hydrolysis of terminal, non-reducing 2,1-linked β-D-fructofuranose residues in fructans
For diagram click here.
Other name(s): β-(2-1)-D-fructan fructohydrolase; β-(2-1)fructan exohydrolase; inulinase; 1-FEH II; 1-fructan exohydrolase; 1-FEH w1; 1-FEH w2; β-(2-1)-linkage-specific fructan-β-fructosidase
Systematic name: β-(2,1)-D-fructan fructohydrolase
Comments: Possesses one of the activities of EC 3.2.1.80, fructan β-fructosidase. While the best substrates are the inulin-type fructans, such as 1-kestose (β-D-fructofuranosyl-(2→1)-β-D-fructofuranosyl α-D-glucopyranoside) and 1,1-nystose (β-D-fructofuranosyl-(2→1)-β-D-fructofuranosyl-(2→1)-β-D-fructofuranosyl α-D-glucopyranoside), some (but not all) levan-type fructans can also be hydrolysed, but more slowly [see EC 3.2.1.154, fructan β-(2,6)-fructosidase]. Sucrose, while being a very poor substrate, can substantially inhibit enzyme activity in some cases.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 1000593-08-7
References:
1. De Roover, J., Van Laere, A., De Winter, M., Timmermans, J.W. and Van den Ende, W. Purification and properties of a second fructan exohydrolase from the roots of Cichorium intybus. Physiol. Plant. 106 (1999) 28-34.
2. Van den Ende, W., Clerens, S., Vergauwen, R., Van Riet, L., Van Laere, A., Yoshida, M. and Kawakami, A. Fructan 1-exohydrolases. β-(2,1)-Trimmers during graminan biosynthesis in stems of wheat? Purification, characterization, mass mapping, and cloning of two fructan 1-exohydrolase isoforms. Plant Physiol. 131 (2003) 621-631. [PMID: 12586886]