Energy coupling of membrane transport and efficiency of sucrose dissimilation in yeast.

Proton coupled transport of α-glucosides via Mal11 into Saccharomyces cerevisiae costs one ATP per imported molecule. Targeted mutation of all three acidic residues in the active site resulted in sugar uniport, but expression of these mutant transporters in yeast did not enable growth on sucrose. We then isolated six unique transporter variants of these mutants by directed evolution of yeast for growth on sucrose.

Coupling efficiency of secondary active transporters.

Secondary active transporters are fundamental to a myriad of biological processes. They use the electrochemical gradient of one solute to drive transport of another solute against its concentration gradient. Central to this mechanism is that the transport of one does not occur in the absence of the other.

Combined engineering of disaccharide transport and phosphorolysis for enhanced ATP yield from sucrose fermentation in Saccharomyces cerevisiae.

Anaerobic industrial fermentation processes do not require aeration and intensive mixing and the accompanying cost savings are beneficial for production of chemicals and fuels. However, the free-energy conservation of fermentative pathways is often insufficient for the production and export of the desired compounds and/or for cellular growth and maintenance. To increase free-energy conservation during fermentation of the industrially relevant disaccharide sucrose by Saccharomyces cerevisiae, we first replaced the native yeast α-glucosidases by an intracellular sucrose phosphorylase from Leuconostoc mesenteroides (LmSPase).

Linker histone H1.0 interacts with an extensive network of proteins found in the nucleolus.

The H1 linker histones are abundant chromatin-associated DNA-binding proteins. Recent evidence suggests that linker histones also may function through protein-protein interactions. To gain a better understanding of the scope of linker histone involvement in protein-protein interactions, we used a proteomics approach to identify H1-binding proteins in human nuclear extracts.