Physiology and genetics of metabolic flux control in Zymomonas mobilis]. Progress report

Abstract

The funded research deals with the physiology and genetics of glycolytic flux control in Zymomonas mobilis. Two fundamental biological questions are begin addressed: First, how do the enzymes of glycolytic pathways act in concert to regulate metabolic flux? Second, what is the role of gene expression in regulating high level synthesis of the glycolytic enzymes in a balance that allows proper glycolytic flux control? The specific objectives of the grant are as follows: 1. To clone the structural and regulatory regions of the Z. mobilis genes encoding glucose-6-phosphate dehydrogenase, phosphoglucose isomerase, enolase, 6-phosphogluconate dehydratase, 2- keto-3-deoxy- 6-phosphogluconate aldolase, glucokinase and fructokinase. 2. To characterize the structure of these genes with respect to nucleotide sequence, transcriptional initiation sites promoter location, evolutionary relatedness to similar genes from other organisms, and organization of these genes on the genome. 3. To investigate the effects of genetically engineered alterations in the levels of the cloned enzymes on metabolic flux and cell growth. 4. To study transcriptional and post-transcriptional regulation of the genes encoding the enzymes of the Entner-Doudoroff pathway. The first two specific objectives have now been fully completed. Significant progress has been made on the fourth objective and work on the third objective is well underway.