BACKGROUND Despite considerable controversy over the inclusion of sucrose in the diets of people with diabetes, the acute metabolism of sucrose is not completely understood. OBJECTIVE Our objective was to investigate the metabolism of the monomeric constituents of sucrose after a high-sucrose meal. DESIGN Three test meals were consumed in a randomized, crossover design by 7 healthy male vol...

In vitro assimilate uptake and metabolism were evaluated in embryos of known age isolated from seeds at mid-podfilling through physiological maturity. The capacity of isolated Wye soybean embryos to take up exogenous [(14)C]sucrose dropped nearly 4-fold in less than 1 week at incipient cotyledon yellowing. This drop in rate of sucrose uptake coincided with cessation of seed growth as well as ra...

Sucrose is the main saccharide used for long-distance transport in plants and plays an essential role energy metabolism; however, there are no analogues real-time imaging live cells. We have optimised a synthetic approach to prepare sucrose including very small (?50 Da or less) Raman tags fructose moiety. Spectroscopic analysis identified alkyne-tagged compound 6 as analogue recognised by endog...

Introduction This report considers the contribution of recent studies on transgenic plants to our current understanding of the role of fructose-2,6-bisphosphate (Fru-2,6-P,) in the regulation of carbon metabolism. From data obtained using such plants we argue that this metabolite is quantitatively important in the control of carbohydrate metabolism in both photosynthetic and non-photosynthetic ...

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...

Sucrose uptake by Corynebacterium glutamicum involves a phosphoenolpyruvate-dependent sucrose phosphotransferase (PTS), but in the absence of fructokinase, further metabolism of the liberated fructose requires efflux of the fructose and reassimilation via the fructose PTS. Mutant strains lacking detectable fructose-transporting PTS activity accumulated fructose extracellularly but consumed sucr...

In celery (Apium graveolens L.), the two major translocated carbohydrates are sucrose and the acyclic polyol mannitol. Their metabolism, however, is different and their specific functions are uncertain. To compare their roles in carbon partitioning and sink-source transitions, developmental changes in (14)CO(2) labeling, pool sizes, and key enzyme activities in leaf tissues were examined. The p...

The formation of mature and fertile pollen grains, taking place inside the anther, depends on supply of assimilates, in the form of sucrose, provided mainly by the leaves. Data is limited, however, with respect to the understanding of sucrose metabolism in microspores and the supporting tissues. The aims of the present work were to 1) follow the changes in total and relative concentrations of s...