[1-beta-D-fructofuranosyl-(2->1)-]m-alpha-D-glucopyranoside;
[1-beta-D-fructofuranosyl-(2->1)-]n-beta-D-fructofuranosyl-(2->6)-alpha-D-glucopyranoside (m > 0; n >= 0)
Comment
Inulins are polysaccharides consisting of linear or branched D-fructofuranosyl chains attached to the fructosyl residue of sucrose by a beta(2->1) linkage. This enzyme catalyses the transfer of the terminal (2->1)-linked -D-fructosyl group of an inulin chain onto O-6 position of the glucose residue of another inulin molecule [1]. For example, if 1-kestose [1F-(beta-D-fructofuranosyl)sucrose] is both the donor and recipient in the reaction shown above, i.e., if m = 1 and n = 1, then the products will be sucrose and 6G-di-beta-D-fructofuranosylsucrose. In this notation, the superscripts F and G are used to specify whether the fructose or glucose residue of the sucrose carries the substituent. Alternatively, this may be indicated by the presence and/or absence of primes (see {iupac/2carb/36#362::http://www.chem.qmul.ac.uk/iupac/2carb/36.html#362}). Sucrose cannot be a donor substrate in the reaction (i.e. m cannot be zero) and inulin cannot act as an acceptor. Side reactions catalysed are transfer of a beta-D-fructosyl group between compounds of the structure 1F-(1-beta-D-fructofuranosyl)m-6G-(1-beta-D-fructofuranosyl)n sucrose, where m >= 0 and n = 1 for the donor, and m >= 0 and n >= 0 for the acceptor.
