3.2.1.123 D133A no hydrolysis of beta-D-Gal-(1->3)-beta-D-GalNAc-(1->4)-(alpha-Neu5Ac-(2->3))-beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide and beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide 751102 3.2.1.123 D342A no hydrolysis of beta-D-Gal-(1->3)-beta-D-GalNAc-(1->4)-(alpha-Neu5Ac-(2->3))-beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide and beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide -, 751102 3.2.1.123 D62A hydrolysis of beta-D-Gal-(1->3)-beta-D-GalNAc-(1->4)-(alpha-Neu5Ac-(2->3))-beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide is 71.9% compared to wild-type enzyme. Hydrolysis of beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide is 83.9% compared to wild-type enzyme -, 751102 3.2.1.123 delN148-G154 loop-deleted mutant Asn148-Gly154, the truncation of loop 4 from Asn148 to Gly154 may increase the space of the crowded sugar-binding cavity, resulting in enhanced activity toward beta-D-Gal-(1->3)-beta-D-GalNAc-(1->4)-(alpha-Neu5Ac-(2->3))-beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide (163%) and decreased activity (46.8%) toward beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide 751102 3.2.1.123 E224D strain C9, severely reduced enzyme activity -, 646701 3.2.1.123 E224Q strain C9, severely reduced enzyme activity -, 646701 3.2.1.123 E233A glycosyl-enzyme intermediate trapped by soaking crystals of the general acid/base knock-out mutant E233A, with an activated sugar donor, 2,4-dinitrophenyl beta-D-lactoside 680770 3.2.1.123 E233D strain M-777, severely reduced enzyme activity -, 646701 3.2.1.123 E233Q strain M-777, severely reduced enzyme activity -, 646701 3.2.1.123 E234D strongly decreased enzyme activity compared with the wild-type enzyme 680753 3.2.1.123 E234Q no activity 680753 3.2.1.123 E339S no hydrolysis of beta-D-Gal-(1->3)-beta-D-GalNAc-(1->4)-(alpha-Neu5Ac-(2->3))-beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide and beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide 751102 3.2.1.123 E341D strongly decreased enzyme activity compared with the wild-type enzyme 680753 3.2.1.123 E341Q no activity 680753 3.2.1.123 E351A mutant glycosidase with glycosynthase activity 695545 3.2.1.123 E351G mutant glycosidase with glycosynthase activity 695545 3.2.1.123 E351M mutant glycosidase with no glycosynthase activity 695545 3.2.1.123 E351R mutant glycosidase with no glycosynthase activity 695545 3.2.1.123 E351S mutant glycosidase with glycosynthase activity, most active enzyme for ganglioside synthesis 695545 3.2.1.123 E351S prevents substrate hydrolysis during crystallization 680770 3.2.1.123 E351S the endo-glycoceramidase II nucleophile mutant E351S has glycosynthase activity 714723 3.2.1.123 E351W mutant glycosidase with no glycosynthase activity 695545 3.2.1.123 E351Y mutant glycosidase with no glycosynthase activity 695545 3.2.1.123 K61A no hydrolysis of beta-D-Gal-(1->3)-beta-D-GalNAc-(1->4)-(alpha-Neu5Ac-(2->3))-beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide and beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide -, 751102 3.2.1.123 N213A no hydrolysis of beta-D-Gal-(1->3)-beta-D-GalNAc-(1->4)-(alpha-Neu5Ac-(2->3))-beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide and beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide -, 751102 3.2.1.123 N265A no hydrolysis of beta-D-Gal-(1->3)-beta-D-GalNAc-(1->4)-(alpha-Neu5Ac-(2->3))-beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide. Hydrolysis of beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide is 2.1% compared to wild-type enzyme 751102 3.2.1.123 Q298A no hydrolysis of beta-D-Gal-(1->3)-beta-D-GalNAc-(1->4)-(alpha-Neu5Ac-(2->3))-beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide and beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide -, 751102 3.2.1.123 S63G the mutant enzyme shows a broader substrate spectrum and significantly increased activity toward bulky substrates 751102 3.2.1.123 W365A no hydrolysis of beta-D-Gal-(1->3)-beta-D-GalNAc-(1->4)-(alpha-Neu5Ac-(2->3))-beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide and beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide 751102 3.2.1.123 Y302A no hydrolysis of beta-D-Gal-(1->3)-beta-D-GalNAc-(1->4)-(alpha-Neu5Ac-(2->3))-beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide and beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-ceramide 751102