Trigger a reaction at some timepoint t

[cel.c...@gmail.com]

Hello,

is it possible to trigger a reaction at some timepoint t? So up until timepoint t and right after timepoint t the reaction should be "inactive" (so in other words the reaction rate should be 0).

The target can only be a species not a reaction. 

I would be happy for suggestions.

Best
Celvic

[Pedro Mendes]

Hi Celvic,

you cannot have reactions as targets but you can have reaction rate
constants as targets. The best way to achieve what you seek is to set a
rate constant to zero and then set it to 1 at the event. You can do this
by multiplying the entire rate equation by such a rate constant. For
example for Michaelis-Menten you can do the following:

active*(Vmax*S/(Km+S))

if the rate constant "active" is set to 0 then the reaction does not
happen. When it is set to 1 then the reaction proceeds with
Michaelis-Menten kinetics.

Pedro

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--
Pedro Mendes, PhD
Professor and Director
Richard D. Berlin Center for Cell Analysis and Modeling
University of Connecticut School of Medicine
group website: http://www.comp-sys-bio.org

[Hoops, Stefan (sh9cq)]

Hello Celvic,

Pedro explained how it can be done. I just like to point out if a
reaction is only active at a single time point T than it is actually
never active at all. You need to have the reaction active for a period
[T1, T2]

Thanks,
Stefan

--
Stefan Hoops, Ph.D.
Research Associate Professor
Biocomplexity Institute & Initiative
University of Virginia
995 Research Park Boulevard
Charlottesville, VA 22911

Phone: +1 540 570 1301
Email: sho...@virginia.edu

[cel.c...@gmail.com]

Hello Pedro,

Thank you alot! This helped me big time.

Best
Celvic