Network Regulation of Expression and Activity of Binding Protein-Dependent ABC-Sugar Transport Systems of Thermus thermophilus

点击翻译按钮获取中文摘要

Thermus thermophilus is a thermophilic bacterium that most likely represents an evolutionary intermediate between today's Gram positive and negative bacteria (15). In respect to sugar transport systems it relies on ABC transporters but as in archaea it has not yet aquired the sugar phosphotransferase system (PTS). We will proceed to study the function of MalK, the common transport ATPase for three ABC systems in T. thermophilus. We will analyse the mechanism of MalK-selectivity in serving the different ABC transporters dependent on the status of transport activity. We propose that in absence of catabolite repression the selection of carbon utilization is mediated by controlling the binding of MalK to the respective permeases and by the specific interaction of the regulatory domain of MalK with proteins involved in sugar metabolism. Vice versa we will follow the possibility that MalK, depending on its engagement in transport will affect metabolic pathways. Here we will focus on glycogen synthesis and degradation.