TY - JOUR
T1 - Ultrasensitive regulation of anapleurosis via allosteric activation of PEP carboxylase
AU - Xu, Yi Fan
AU - Amador-Noguez, Daniel
AU - Reaves, Marshall Louis
AU - Feng, Xiao Jiang
AU - Rabinowitz, Joshua D.
N1 - Funding Information:
We thank Princeton University colleagues C. Doucette for the ppc deletion strain and A. Hottes for the pCA24N-ppc plasmid; J. Park for the flux calculations; A. Michaelis and Z. Gitai for the microscopy; D. Perlman, W. Lu, K. Saw and H. Shwe for protein mass spectrometry; and N. Wingreen for helpful discussions. This research was funded by US National Science Foundation (NSF) CAREER award MCB-0643859, Joint US Department of Energy–Air Force Office of Scientific Research award DOE DE-SC0002077–AFOSR FA9550-09-1-0580, the US National Institutes of Health Center for Quantitative Biology award P50 GM071508 and NSF grant CBET-0941143. M.L.R. was supported by NSF Graduate Research Fellowship DGE-0646086.
PY - 2012/6
Y1 - 2012/6
N2 - Anapleurosis is the filling of the tricarboxylic acid cycle with four-carbon units. The common substrate for both anapleurosis and glucose phosphorylation in bacteria is the terminal glycolytic metabolite phosphoenolpyruvate (PEP). Here we show that Escherichia coli quickly and almost completely turns off PEP consumption upon glucose removal. The resulting buildup of PEP is used to quickly import glucose if it becomes available again. The switch-like termination of anapleurosis results from depletion of fructose-1,6-bisphosphate (FBP), an ultrasensitive allosteric activator of PEP carboxylase. E. coli expressing an FBP-insensitive point mutant of PEP carboxylase grow normally when glucose is steadily available. However, they fail to build up PEP upon glucose removal, grow poorly when glucose availability oscillates and suffer from futile cycling at the PEP node on gluconeogenic substrates. Thus, bacterial central carbon metabolism is intrinsically programmed with ultrasensitive allosteric regulation to enable rapid adaptation to changing environmental conditions.
AB - Anapleurosis is the filling of the tricarboxylic acid cycle with four-carbon units. The common substrate for both anapleurosis and glucose phosphorylation in bacteria is the terminal glycolytic metabolite phosphoenolpyruvate (PEP). Here we show that Escherichia coli quickly and almost completely turns off PEP consumption upon glucose removal. The resulting buildup of PEP is used to quickly import glucose if it becomes available again. The switch-like termination of anapleurosis results from depletion of fructose-1,6-bisphosphate (FBP), an ultrasensitive allosteric activator of PEP carboxylase. E. coli expressing an FBP-insensitive point mutant of PEP carboxylase grow normally when glucose is steadily available. However, they fail to build up PEP upon glucose removal, grow poorly when glucose availability oscillates and suffer from futile cycling at the PEP node on gluconeogenic substrates. Thus, bacterial central carbon metabolism is intrinsically programmed with ultrasensitive allosteric regulation to enable rapid adaptation to changing environmental conditions.
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U2 - 10.1038/nchembio.941
DO - 10.1038/nchembio.941
M3 - Article
C2 - 22522319
AN - SCOPUS:84861455370
SN - 1552-4450
VL - 8
SP - 562
EP - 568
JO - Nature Chemical Biology
JF - Nature Chemical Biology
IS - 6
ER -