Journal of Pure and Applied MicrobiologyVol. 9 No. Special Edition May. 2015

The Response to the Environmental Stress of Key Enzymes Activities in Central Carbon Metabolic System of E. coli

Bin Rui1# Yadong Fan1#, Yongkang Wang1, Yuanshuai Li1, Xiaoyao Xie2* and Han Wena*

1School of Life Science, Anhui Agricultural University, 230026, Hefei, China. 2Key†laboratory†of Information and Computing†Science†Guizhou Province, Guizhou Normal University, 550001, Guiyang, China.

Received on 09 February 2015 and accepted on 20 April 2015

 

ABSTRACT

The response of central carbon metabolism system of E.coli to environmental changes is a comparatively simple and meaningful model in the interaction between organisms and environment. We have simulated environmental changes with sodium chloride and paraquat. Analyses of key enzymes activities in branch pathways confirmed the response to environmental stress of central carbon metabolism system of E.coli and provided a new visual angle for the regulation mechanism. In 0.2 M NaCl permeability environment, 6-phosphate glucose dehydrogenase/phosphate glucose isomerase revealed significant reduction (~ 69%), the central carbon metabolism flow convert partially from PP pathway to glycolysis pathway. Itís just the opposite with oxidative stress situation. Pyruvate kinase and PEP carboxylase is another important adjustable node. The ratio of pyruvate kinase/PEP carboxylase revealed significant reduction (~ 77%) in permeability environment, which is consistent with the decline trend under oxidative stress.

Keywords : Central carbon metabolism; Environmental stress; Key enzymes; Regulatory mechanism.