Document Detail

Control limits for accumulation of plant metabolites: brute force is no substitute for understanding.
MedLine Citation:
PMID:  23301840     Owner:  NLM     Status:  Publisher    
Which factors limit metabolite accumulation in plant cells? Are theories on flux control effective at explaining the results? Many biotechnologists cling to the idea that every pathway has a rate limiting enzyme and target such enzymes first in order to modulate fluxes. This often translates into large effects on metabolite concentration, but disappointing small increases in flux. Rate limiting enzymes do exist, but are rare and quite opposite to what predicted by biochemistry. In many cases however, flux control is shared among many enzymes. Flux control and concentration control can (and must) be distinguished and quantified for effective manipulation. Flux control for several 'building blocks' of metabolism is placed on the demand side, and therefore increasing demand can be very successful. Tampering with supply, particularly desensitizing supply enzymes, is usually not very effective, if not dangerous, because supply regulatory mechanisms function to control metabolite homeostasis. Some important, but usually unnoticed, metabolic constraints shape the responses of metabolic systems to manipulation: mass conservation, cellular resource allocation and, most prominently, energy supply, particularly in heterotrophic tissues. The theoretical basis for this view shall be explored with recent examples gathered from the manipulation of several metabolites (vitamins, carotenoids, amino acids, sugars, fatty acids, polyhydroxyalkanoates, fructans and sugar alcohols). Some guiding principles are suggested for an even more successful engineering of plant metabolism.
Piero Morandini
Publication Detail:
Type:  JOURNAL ARTICLE     Date:  2013-1-10
Journal Detail:
Title:  Plant biotechnology journal     Volume:  -     ISSN:  1467-7652     ISO Abbreviation:  Plant Biotechnol. J.     Publication Date:  2013 Jan 
Date Detail:
Created Date:  2013-1-10     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  101201889     Medline TA:  Plant Biotechnol J     Country:  -    
Other Details:
Languages:  ENG     Pagination:  -     Citation Subset:  -    
Copyright Information:
Plant Biotechnology Journal © 2013 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.
Department of Biosciences, University of Milan and CNR Institute of Biophysics, Milan, Italy.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Electrochemical Study of Anticancer Drug Daunorubicin at a Water/Oil Interface: Drug Lipophilicity a...
Next Document:  Synthesis of Chiral ?-Iodo- and Vinylorganophosphorus(V) Compounds by Fragmentation of Carbohydrate ...