Near-Perfect Adaptation in Bacterial Chemotaxis

1
Near-Perfect Adaptation in Bacterial
Chemotaxis Yang Yang Sima SetayeshgarDepartment
of Physics, Indiana University, Bloomington,
Indiana 47405
Methylation
Phosphorylation
k10 (s-1)
These conditions are consistent with those
obtained in previous works from analysis of a
detailed, two-state receptor model6.
k3c (s-1)
6 B. Mello et al. Biophysical Journal 84, 2943
(2003).
k-2 (M-1s-1)
k-2 (M-1s-1)
Literature value4
4 P. A. Spiro et al. Proc. Natl. Acad. Sci. USA
94, 7263 (1997)
4 P. A. Spiro et al. Proc. Natl. Acad. Sci.
(USA ) 94, 7263 (1997)
k10 (s-1)
Adaptation is an important and generic property
of biological systems. Adaptive responses occur
over a wide range of time scales, from fractions
of a second in neural systems, to millions of
years in the evolution of species
k3c (s-1)
k-2 (M-1s-1)
Figure from 1 V. Sourjik et al. Proc. Natl.
Acad. Sci. 99, 123 (2002).
Literature value4
4 P. A. Spiro et al. Proc. Natl. Acad. Sci. USA
94, 7263 (1997)
Figure from 2 U. Alon et al. Nature 397, 168
(1999)
Attractant 30 µM aspartate. Repellent 100 µM
NiCl2
We use the well-characterized chemotaxis network
in E. coli as a prototype for exploring physical
principles underlying the design of biological
signaling networks from the standpoint of
adapation and robustness.