The lac carrier of Escherichia coli enables lactose to pass across the cytoplasmic membrane and to accumulate within the cell. The energy cost of concentrative sugar uptake is borne by the transmembrane proton free-energy gradient (A&+) as envisaged by Mitchell (1977) in the form of pH and electrical potential gradients (ApH and Av). Obligate 1 : 1 proton/galactoside symport via the permease co...

We report the complete primary and secondary structures of a metas tasis-associated M, 34,000 galactoside-binding lectin. The polypeptide sequence (264 amino acids) was derived from the nucleotide sequence of three overlapping complementary DNA clones isolated from Xgtll and XgtlO phage libraries of UV-induced murine fibrosarcomas. Striking features of the polypeptide sequence are two distinct ...

The objective of this research was to survey the antioxidant functional role of the main anthocyanins of blueberries in endothelial cells. Changes on the reactive oxygen species (ROS), xanthine oxidase-1 (XO-1), superoxide dismutase (SOD), and heme oxygenase-1 (HO-1) in cells of malvidin and the two glycosides were investigated. The results showed that these anthocyanins decreased the levels of...

A particulate subcellular fraction from Escherichia coli K-12 induced in anaerobic sn-glycerol 3-phosphate (G3P) dehydrogenase and fumarate reductase can catalyze under anaerobic conditions the transfer of hydrogens from G3P to fumarate, with attendant generation of high-energy phosphate. The phsophorylation process is more sensitive than the transhydrogenation process to inhibition by the dete...

Galectins are involved in many cellular processes due to their ability to bind carbohydrates. Understanding their functions has shown the necessity for potent and specific galectin inhibitors. Human galectin-7 (hGal-7), in particular, has been highlighted as an important marker in many types of cancer by either inhibiting or promoting tumour growth. Producing ligands able to selectively target ...

Beta-galactoside-binding lectins were isolated from various calf tissues and from chicken hearts by affinity chromatography on asialofetuin-Sepharose, and were compared with respect to biochemical characteristics, binding properties, antigenic cross-reactivity, and cellular localization. The lectins are all thiol group-requiring, divalent cation-independent dimers, of apparent monomer mol wt 12...

Of 44 fluorogenic substrates tested for their ability to differentiate species of fecal streptococci, four yielded species-differentiating reactions. The remaining substrates either yielded uniformly positive, negative, or variable strain-dependent reactions. One substrate, 4-methylumbelliferone-alpha-D-galactoside, was hydrolyzed by Streptococcus bovis and S. faecium and its biotypes. 4-Methyl...