Melibiose

About: Melibiose is a research topic. Over the lifetime, 1002 publications have been published within this topic receiving 27300 citations. The topic is also known as: Melibiose.

Agent for improving hepatic function

Abstract: PROBLEM TO BE SOLVED: To provide a composition usable as pharmaceuticals, foods and drinks free from side effect owing to the use of a food material as the component and useful for the treatment and/or prevention of hepatic diseases such as acute hepatitis, hepatic insufficiency, chronic hepatitis, jecur adiposum and hepatocirrhosis. SOLUTION: The hepatic function improving agent or composition contains a nitrogen-containing compound acting as a methyl donor in the body (choline, betaine, methionine, S-adenosylmethionine, vitamin B12 , folic acid, carnitine, etc.), and a hardly digestible oligosaccharide containing galactose (raffinose, lactulose, soybean oligosaccharide, galactooligosaccahride, melibiose, etc.), as active components.

Identification and Characterization of the Major Carbohydrate-Binding Proteins in Chicken Serum as Immunoglobulins.

Abstract: To isolate the major carbohydrate-binding proteins in pooled normal chicken sera, affinity chromatographies on different affinity gels were carried out. From the results obtained, normal chicken sera were found to contain serum proteins which were Ca2+-dependently and -independently reactive with mannose, N-acetylglucosamine, N-acetylgalactosamine, L-fucose, melibiose, lactose, unsubstituted Sepharose 4B, and SeaKem HE agarose. They were electrophoretically and antigenically found to be mainly IgM and IgG.

Mutants of the lactose carrier of Escherichia coli which show altered sugar recognition plus a severe defect in sugar accumulation.

Abstract: Lactose and melibiose are actively accumulated by the wild-type Escherichia coli lactose carrier, which is an integral membrane protein energized by the proton motive force. Mutants of the E. coli lactose carrier were isolated by their ability to grow on minimal plates with succinate plus IPTG in the presence of the toxic lactose analog β-thio-o-nitrophenylgalactoside (TONPG). TONPG-resistant mutants were streaked on melibiose MacConkey indicator plates, and red clones were picked. These melibiose positive mutants were then streaked on lactose MacConkey plates, and white clones were picked. Transport assays indicated that the mutants had altered sugar recognition and a defect in sugar accumulation. The mutants had a poor apparent K m for both lactose and melibiose in transport. One mutant had almost no ability to take up lactose, but melibiose downhill transport was 58% (V max ) of normal. All of the mutants accumulated methyl-α-d-galactopyranoside (TMG) to only 8% or less of normal, and two failed to accumulate. Immunoblot analysis of the mutant lactose carrier proteins indicated that loss of sugar transport activity was not due to loss of expression in the membrane. Nucleotide sequencing of the lacY gene from the mutants revealed changes in the following amino acids of the lactose carrier: M23I, W151L, G257D, A295D and G377V. Two of the mutants (G257D and G377V) are novel in that they represent the first amino acids in periplasmic loops to be implicated with changes in sugar recognition. We conclude that the amino acids M23, W151, G257, A295 and G377 of the E. coli lactose carrier play either a direct or an indirect role in sugar recognition and accumulation.

Truncation of Gal4p explains the inactivation of the GAL/MEL regulon in both Saccharomyces bayanus and some Saccharomyces cerevisiae wine strains.

Abstract: In the past, the galactose-negative (Gal(-)) phenotype was a key physiological character used to distinguish Saccharomyces bayanus from S. cerevisiae In this work, we investigated the inactivation of GAL gene networks in S. bayanus, which is an S. uvarum/S. eubayanus hybrid, and in S. cerevisiae wine strains erroneously labelled 'S. bayanus'. We made an inventory of their GAL genes using genomes that were either available publicly, re-sequenced by us, or assembled from public data and completed with targeted sequencing. In the S. eubayanus/S. uvarum CBS 380(T) hybrid, the GAL/MEL network is composed of genes from both parents: from S. uvarum, an otherwise complete set that lacks GAL4, and from S. eubayanus, a truncated version of GAL4 and an additional copy of GAL3 and GAL80 Similarly, two different truncated GAL4 alleles were found in S. cerevisiae wine strains EC1118 and LalvinQA23. The lack of GAL4 activity in these strains was corrected by introducing a full-length copy of S. cerevisiae GAL4 on a CEN4/ARS plasmid. Transformation with this plasmid restored galactose utilisation in Gal(-) strains, and melibiose fermentation in strain CBS 380(T) The melibiose fermentation phenotype, formerly regarded as characteristic of S. uvarum, turned out to be widespread among Saccharomyces species.