Endohydrolysis of (1->4)-beta-D-linkages between D-galactose 4-sulfate and 3,6-anhydro-D-galactose-2-sulfate in iota-carrageenans
The main products of hydrolysis are iota-neocarratetraose sulfate and iota-neocarrahexaose sulfate. iota-Neocarraoctaose is the shortest substrate oligomer that can be cleaved. Unlike EC 22.214.171.124, beta-agarase and EC 126.96.36.199, kappa-carrageenase, this enzyme proceeds with inversion of the anomeric configuration. iota-Carrageenan differs from kappa-carrageenan by possessing a sulfo group on O-2 of the 3,6-anhydro-D-galactose residues, in addition to that present in the kappa-compound on O-4 of the D-galactose residues.