Biomaterial Database

On the sign pattern of metabolic control coefficients. 1996

A K Sen

Department of Mathematical Sciences, Purdue University School of Science, Indianapolis, IN 46202, USA.

The sign of a flux (concentration) control coefficient of an enzyme determines if the metabolic flux (metabolite concentration) will increase or decrease when the enzyme concentration is increased/decreased. In general, the sign of a control coefficient depends on the magnitudes of the enzyme elasticities, fluxes etc. It is shown that in many pathways some (or all) of the control coefficients may have fixed signs irrespective of the magnitudes of the elasticities and fluxes. The remaining control coefficients are sign-indeterminate. The enzymes and metabolites whose control coefficients are sign-indeterminate can be identified in a heuristic fashion directly from the topology of the metabolic pathway, i.e., location of feedback-feedforward loops, location of branches, presence of isoenzymes etc. In other pathways such as those containing a substrate cycle, none of the control coefficients of the enzymes can have a fixed sign; a control coefficient may be positive, negative or zero depending on the actual magnitudes of the elasticities and velocities.

UI	MeSH Term	Description	Entries
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D004798	Enzymes	Biological molecules that possess catalytic activity. They may occur naturally or be synthetically created. Enzymes are usually proteins, however CATALYTIC RNA and CATALYTIC DNA molecules have also been identified.	Biocatalyst,Enzyme,Biocatalysts
D005246	Feedback	A mechanism of communication within a system in that the input signal generates an output response which returns to influence the continued activity or productivity of that system.	Feedbacks
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D019295	Computational Biology	A field of biology concerned with the development of techniques for the collection and manipulation of biological data, and the use of such data to make biological discoveries or predictions. This field encompasses all computational methods and theories for solving biological problems including manipulation of models and datasets.	Bioinformatics,Molecular Biology, Computational,Bio-Informatics,Biology, Computational,Computational Molecular Biology,Bio Informatics,Bio-Informatic,Bioinformatic,Biologies, Computational Molecular,Biology, Computational Molecular,Computational Molecular Biologies,Molecular Biologies, Computational