We present the detection of single beta-galactosidase molecules from Escherichia coli (Ecbeta Gal) using deep UV laser-based fluorescence lifetime microscopy. The native fluorescence from intrinsic tryptophan emission has been observed after one-photon excitation at 266 nm. Applying the time-resolved single-photon counting method, we investigated the fluorescence lifetime distribution and the b...

The beta-galactosidase activities arising from Tn5lac insertions in several genes required for antibiotic TA production were measured under different growth conditions. In all of the non-TA-producing mutants, the beta-galactosidase specific activity was higher when the cells were grown in nutrient-limited 0.5CTS medium (0.5% Casitone plus alanine, serine, and glucose) than in rich 2CT medium (2...

It has been reported that the immune response due to alpha-Gal epitopes is an important factor in tissue valve failure. The elimination of the interaction between the natural anti-Gal antibodies and alpha-gal epitopes on the xenografts is a prerequisite to the success of xenografts in humans. Previously, we reported that the green coffee bean alpha-galactosidase could remove all alpha-Gal epito...

For construction of bifunctionally active membrane-bound fusion proteins, we designed plasmids encoding fusion proteins in which the carboxyl terminus of Escherichia coli proline carrier was joined to the amino terminus of E. coli beta-galactosidase directly or with a collagen linker inserted between the two. The expressions of these fusion proteins complemented deficiencies in both proline tra...

Lactose is the only soluble and economically feasible carbon source for the production of cellulases or heterologous proteins regulated by cellulase expression signals by Hypocrea jecorina (Trichoderma reesei). We investigated the role of the major beta-galactosidase of H. jecorina in lactose metabolism and cellulase induction. A genomic copy of the bga1 gene was cloned, and this copy encodes a...

Beta-galactosidase (ß-D-galactoside galactohydrolase, EC 3.2.1.23), has tremendous potential in research and application in various fields like food, bioremediation, biosensor, diagnosis and treatment of disorders. The sources of the betagalactosidase are microorganisms, plants and animals. Microbial beta-galactosidase is of much interest because of their thermostability, thermoacidophilic and ...

Research on the mode of action of auxin in the promotion of growth has shown that auxin treatment leads to hydrogen ion secretion and wall acidification. It has recently been reported that auxin stimulates cell wall beta-galactosidase activity in Avena coleoptiles, presumably by causing cell wall acidification, since the pH optimum for the enzyme is about 5.0. It has been suggested that enhance...