fulltext.study @t Gmail

Analysis of polyhydroxybutyrate flux limitations by systematic genetic and metabolic perturbations

Paper ID Volume ID Publish Year Pages File Format Full-Text
31871 44847 2010 9 PDF Available
Title
Analysis of polyhydroxybutyrate flux limitations by systematic genetic and metabolic perturbations
Abstract

Poly-3-hydroxybutyrate (PHB) titers in Escherichia coli have benefited from 10+ years of metabolic engineering. In the majority of studies, PHB content, expressed as percent PHB (dry cell weight), is increased, although this increase can be explained by decreases in growth rate or increases in PHB flux. In this study, growth rate and PHB flux were quantified directly in response to systematic manipulation of (1) gene expression in the product-forming pathway and (2) growth rates in a nitrogen-limited chemostat. Gene expression manipulation revealed acetoacetyl-CoA reductase (phaB) limits flux to PHB, although overexpression of the entire pathway pushed the flux even higher. These increases in PHB flux are accompanied by decreases in growth rate, which can be explained by carbon diversion, rather than toxic effects of the PHB pathway. In chemostats, PHB flux was insensitive to growth rate. These results imply that PHB flux is primarily controlled by the expression levels of the product forming pathway and not by the availability of precursors. These results confirm prior in vitro measurements and metabolic models and show expression level is a major affecter of PHB flux.

Keywords
Poly-3-hydroxybutyrate; PHB; Chemostat; Flux control; Overexpression
First Page Preview
Analysis of polyhydroxybutyrate flux limitations by systematic genetic and metabolic perturbations
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us
Publisher
Database: Elsevier - ScienceDirect
Journal: Metabolic Engineering - Volume 12, Issue 3, May 2010, Pages 187–195
Authors
, , , ,
Subjects
Physical Sciences and Engineering Chemical Engineering Bioengineering
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us