...Dorothy Beckett Biotin, which serves as a carboxyl group carrier in reactions catalyzed by biotin-dependent carboxylases, is essential for life in most organisms. To function in carboxylate transfer, the vitamin must be post-translationally linked to a specific lysine residue on the biotin carboxyl...

...-phosphates. This potential is limited by its high specificity. A variety of approaches have been taken to identify galactokinase variants which are more promiscuous. These have broadened galactokinase's specificity to include a wide range of D - and L -sugars. Initial studies suggest that some...

.... In addition, the paradox that Ca 2+ is involved in the transduction of signals that result in opposite end responses (stomatal opening and closure) might be accounted for by the generation of stimulus-specific Ca 2+ signatures, such that increases in [Ca 2+ ] cyt exhibit unique spatial and temporal...