Function and Regulation of the Pyruvate Transporter CstA in Escherichia coli.
Ana Florencia GasperottiStephanie GöingElena Fajardo-RuizIgnasi FornéKirsten JungPublished in: International journal of molecular sciences (2020)
Pyruvate is a central metabolite that connects many metabolic pathways in living organisms. To meet the cellular pyruvate requirements, the enterobacterium Escherichia coli has at least three pyruvate uptake systems-the H+/pyruvate symporter BtsT, and two thus far less well-characterized transporters, YhjX and CstA. BtsT and CstA belong to the putative carbon starvation (CstA) family (transporter classification TC# 2.A.114). We have created an E. coli mutant that cannot grow on pyruvate as the sole carbon source and used it to characterize CstA as a pyruvate transporter. Transport studies in intact cells confirmed that CstA is a highly specific pyruvate transporter with moderate affinity and is energized by a proton gradient. When cells of a reporter strain were cultured in complex medium, cstA expression was maximal only in stationary phase. A DNA affinity-capture assay combined with mass spectrometry and an in-vivo reporter assay identified Fis as a repressor of cstA expression, in addition to the known activator cAMP-CRP. The functional characterization and regulation of this second pyruvate uptake system provides valuable information for understanding the complexity of pyruvate sensing and uptake in E. coli.
Keyphrases
- escherichia coli
- mass spectrometry
- induced apoptosis
- poor prognosis
- high throughput
- crispr cas
- cell cycle arrest
- binding protein
- healthcare
- oxidative stress
- immune response
- inflammatory response
- klebsiella pneumoniae
- endothelial cells
- capillary electrophoresis
- toll like receptor
- health information
- nuclear factor
- ms ms
- pseudomonas aeruginosa
- biofilm formation
- wild type