Transgenic derivatives of sugarcane cultivar Q117, with reduced acid invertase activity, were used to investigate the role of this enzyme in sucrose metabolism in the sugarcane culm. Despite more than 70% reduction in the level of acid invertase activity in the immature internodes, no significant changes in either sucrose load or purity were evident. Radiolabelling experiments indicated no sign...

BACKGROUND In contrast to man the majority of higher plants use sucrose as mobile carbohydrate. Accordingly proton-driven sucrose transporters are crucial for cell-to-cell and long-distance distribution within the plant body. Generally very negative plant membrane potentials and the ability to accumulate sucrose quantities of more than 1 M document that plants must have evolved transporters wit...

Rat liver mitochondria became permeabilized to sucrose according to an apparent first-order process after accumulating 35 nmol of Ca2+/mg of protein in the presence of 2.5 mM-Pi, but not in its absence. A fraction (24-32%) of the internal space remains sucrose-inaccessible. The rate constant for permeabilization to sucrose decreases slightly when the pH is decreased from 7.5 to 6.5, whereas the...

Sucrose is perhaps the most efficient carbohydrate for the promotion of dental caries in humans, and the primary caries pathogen Streptococcus mutans encodes multiple enzymes involved in the metabolism of this disaccharide. Here, we engineered a series of mutants lacking individual or combinations of sucrolytic pathways to understand the control of sucrose catabolism and to determine whether as...

Sucrose is an important disaccharide used as a substrate in many industrial applications. It is a major component of molasses, a cheap by-product of the sugar industry. Unfortunately, not all industrially relevant organisms, among them Pseudomonas putida, are capable of metabolizing sucrose. We chose a metabolic engineering approach to circumvent this blockage and equip P. putida with the activ...

Anthocyanins are secondary metabolites, which play an important role in the physiology of plants. Both sucrose and hormones regulate anthocyanin synthesis. Here, the interplay between sucrose and plant hormones was investigated in the expression of sucrose-regulated genes coding for anthocyanin biosynthetic enzymes in Arabidopsis seedlings. The expression pattern of 14 genes involved in the ant...

The capacity of plant heterotrophic organs to transport and accumulate incoming nutrients (mostly in the form of sucrose) directly impacts their final size, crop productivity and nutritional value. Endocytosis as a mechanism for nutrient uptake in heterotrophic cells was investigated using suspension culture cells of sycamore (Acer pseudoplatanus L.) and the endocytic inhibitors wortmannin and ...

The Sugar Research Institute (SRI) in Australia provided the SMRI with a Sucrose Analyser for evaluation. Although the Sucrose Analyser is designed for online measurement of sucrose concentrations, this application describes the direct measurement of sucrose in factory streams in a laboratory environment. The Sucrose Analyser provides a quick and cost effective way of estimating the sucrose con...

Laboratory mice drink little sucrose solution on initial exposure, but later develop a strong preference for sucrose over water that plateaus after a few days. Both the initial neophobia and later plateau of sucrose intake may involve central oxytocin (OT) signaling pathways. If so, then mice that lack the gene for OT [OT knockout (KO)] should exhibit enhanced initial and sustained sucrose inta...

Sucrose-rich diets have repeatedly been observed to have co-carcinogenic actions in colon and liver of rats and to increase the number of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) induced aberrant crypt foci in rat colon. To investigate a possible interaction between sucrose and IQ on the genotoxicity in rat liver and colon, we gave Big Blue rats a diet containing sucrose (0%, 3.45% or 13.4%...