Background Acetylated 4-O-(methyl)glucuronoxylan (GX) is the main hemicellulose in deciduous hardwood, and comprises a β-(1→4)-linked xylopyranosyl (Xylp) backbone substituted by both acetyl groups and α-(1→2)-linked 4-O-methylglucopyranosyluronic acid (MeGlcpA). Whereas enzymes that target singly acetylated Xylp or doubly 2,3-O-acetyl-Xylp have been well characterized, those targeting (2-O-MeG...

The importance of O-acetyl groups to the immunogenicity of Neisseria meningitidis serogroup A polysaccharide (PS) was examined in studies using human sera and mouse immunization. In 17 of 18 postimmunization human sera, inhibition enzyme-linked immunosorbent assay indicated that the majority of antibodies binding to serogroup A PS were specific for epitopes involving O-acetyl groups. Studies wi...

Background & Aims: In the recent years, increasing rate of using electronic devices which generate electromagnetic fields , has caused researchers, attention to the effects of electromagnetic fields on human health. The aim of this study is to investigate the effect of prolonged exposure to extremely low frequency electromagnetic fields(ELF) on the Cholinergic system in the small intestine of r...

b a ckground: the role of lectins is important in interaction between pathogens and mosquito vectors. this study was performed to identify agglutinin activities of protein molecules on the midgut of culex pipiens . m e t hods: c u lex pipiens was reared in insectray condition and the midguts of males and females (blood fed and un- fed) were dissected separately in tris-hcl buffer. the extracts ...

Crystalline 60 per cent active acetyl pepsin has 7 acetyl groups per mol of pepsin, 3 of which are readily hydrolyzed in acid at pH 0.0 or in weak alkali at pH 10.0. The tyrosine-tryptophane content of this acetylated pepsin, measured colorimetrically, is less than pepsin by three tyrosine equivalents. Hydrolysis at pH 0.0 or pH 10.0 of the 3 acetyl groups results in a concomitant increase in t...

Wood is a porous three dimensional, hydroscopic, viscoelastic, anisotropic bio-polymer composite composed of an interconnecting matrix of cellulose, hemicelluloses and lignin with minor amounts of inorganic elements and organic extractives. Some, but not all, of the cell wall polymer hydroxyl groups are accessible to moisture and these accessible hydroxyls form hydrogen bonds with water. As the...

The ordinarily free amino groups of N-terminal residues in polypeptide chains are blocked in some instances by acetyl groups, e.g., in melanocyte-stimulating hormone (a-MSH),I and in the following proteins: horse heart cytochrome c,2 hemoglobin F1,3 egg albumin,4 histones,5 turnip yellow mosaic virus (TYMV),6 and tobacco mosaic virus (TMV) proteins.7 The question arises whether the introduction...

wood is a porous three dimensional, hydroscopic, viscoelastic, anisotropic bio-polymer composite composed of an interconnecting matrix of cellulose, hemicelluloses and lignin with minor amounts of inorganic elements and organic extractives. some, but not all, of the cell wall polymer hydroxyl groups are accessible to moisture and these accessible hydroxyls form hydrogen bonds with water. as the...