Untitled Document

(*) Summary.

Darwinism has often been accused of being tautological. It states that
the fittest organisms have a better chance to survive and reproduce, but
does not say how to identify those fittest organisms a priori. Only one
generation later it is possible to pint point the fittest organisms by
looking at the ones that produced the largest offsprings. One way to
break this cycling reasoning is to establish the characteristics that
optimize an organism performance. We hypothesize that the optimization
process involves several aspects like: short response times to
environmental changes, little noise in the value of physiological
relevant values, and low energy consumption. This hypothesis is tested
in one of the best know and most extensively studied metabolic pathways:
that of tryptophan biosynthesis in E. coli (also known as the tryptophan
operon).

(**) Biodata.

Professor Moises Santillan is the main investigator of the Computational
Systems Biology Laboratory at Centro de Investigacion y Estudios
Avanzados del IPN, Unidad Monterrey, Mexico.

Prof. Santillan is interested in a variety of dynamical, biological
problems, ranging from the levels of molecules (molecular motors) and
cells (gene regulatory networks, signalling pathways, and cell
motility), to the levels of organs (muscle contraction) and whole
organisms (regulation of blood cell production). In particular, he
studies the regulatory mechanisms underlying the dynamic behaviour of
biological systems. In his lab, they aim at understanding how such
mechanisms optimize the systems’ performance: short response times, low
entropy production, high efficiency of energy conversion, etc. Given the
complexity of those systems, several techniques are necessary to
investigate their dynamics. Among others, in Prof. Santillan's lab they
employ: mathematical modelling with ode’s, non-linear dynamics,
analytical stochastic modelling and analysis, Monte Carlo simulation,
irreversible thermodynamics, statistical physics, and (recently)
experimental molecular biology.