Crystal structure and sugar-binding ability of the C-terminal domain of N-acetylglucosaminyltransferase IV establish a new carbohydrate-binding module family.

N-glycans are modified by glycosyltransferases in the endoplasmic reticulum and Golgi apparatus. N-acetylglucosaminyltransferase IV (GnT-IV) is a Golgi-localized glycosyltransferase that synthesizes complex-type N-glycans in vertebrates. This enzyme attaches N-acetylglucosamine (GlcNAc) to the α-1,3-linked mannose branch of the N-glycan core structure via a β-1,4 linkage.

Multiple Stimuli-Responsive Supramolecular Gel Formed from Modified Adenosine.

Urea derivatives 1 and 2, synthesized from adenosine, were designed as low-molecular-weight gelators. Hydrophobic groups have been introduced into all or part of the hydroxy groups of the hydrophilic ribose moiety of 1 and 2 to control the solvophilicity of the molecules and their aggregates. Compound 2 selectively formed supramolecular gels in halogenated solvents such as chloroform and 1,2-dichloroethane.

Effect of Alkyl Chain Length of N-Alkyl-N'-(2-benzylphenyl)ureas on Gelation.

Urea derivatives that were substituted with a 2-benzylphenyl group and an alkyl group functioned as low molecular weight gelators for various organic solvents and ionic liquids. Urea derivatives with long alkyl chains were effective for the gelation of polar solvents. However, they were not suitable for the gelation of non-polar solvents, whereas urea derivatives with short alkyl chains were effective.

Expression and characterization of silkworm Bombyx mori β-1,2-N-acetylglucosaminyltransferase II, a key enzyme for complex-type N-glycan biosynthesis.

N-glycans are involved in various physiological functions and their structures diverge among different phyla and kingdoms. Insect cells mainly produce high mannose-type and paucimannose-type glycans but very few mammalian-like complex-type glycans. However, many insects possess genes for proteins homologous to the enzymes involved in complex-type N-glycan synthesis in mammalian cells, and their N-glycosylation pathway is incompletely understood compared with that of mammals.