Document Detail


The proteolytic degradation in vitro of the NADPH-protochlorophyllide oxidoreductase of barley (Hordeum vulgare L.).
MedLine Citation:
PMID:  6696447     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
A cell-free membrane system has been developed from isolated barley etioplasts which displays a highly selective decrease of the NADPH-protochlorophyllide oxidoreductase in vitro which is indistinguishable from that observed previously in the intact plant. The rapid breakdown of the enzyme protein in vitro is caused by a membrane-bound proteolytic activity. The protease is essentially independent of pH in the physiological pH range of 6 to 8.5. The optimum temperature for the reaction is approximately 40 degrees C. In the presence of excessive protochlorophyllide the enzyme is no longer degraded or inactivated during illumination of dark-grown plants. In the isolated membrane fraction protochlorophyllide also enhances the stability of the enzyme, a similar effect is exerted by NADPH but not by NADH. The results suggest that the inactivation of the NADPH-protochlorophyllide oxidoreductase is influenced by the interaction of the enzyme with protochlorophyllide and NADPH. In the absence of these two components the enzyme becomes susceptible to proteolytic degradation.
Authors:
I Häuser; K Dehesh; K Apel
Related Documents :
22623307 - Directed evolution of carotenoid synthases for the production of unnatural carotenoids.
3663167 - Interactions of nicotinamide-adenine dinucleotide phosphate analogues and fragments wit...
27457 - Allosteric transformation of reduced nicotinamide adenine dinucleotide (phosphate) oxid...
365527 - Biodegradative threonine dehydratase. reduction of ferricyanide by an intermediate of t...
10963787 - Action of metalloproteinases mutalysin i and ii on several components of the hemostatic...
19873237 - Studies on cell metabolism and cell division : v. cytochrome oxidase activity in the eg...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Archives of biochemistry and biophysics     Volume:  228     ISSN:  0003-9861     ISO Abbreviation:  Arch. Biochem. Biophys.     Publication Date:  1984 Feb 
Date Detail:
Created Date:  1984-03-12     Completed Date:  1984-03-12     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0372430     Medline TA:  Arch Biochem Biophys     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  577-86     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Cereals / metabolism*
Hordeum / metabolism*
Hydrogen-Ion Concentration
Light
Oxidoreductases / metabolism*
Oxidoreductases Acting on CH-CH Group Donors*
Temperature
Time Factors
Chemical
Reg. No./Substance:
EC 1.-/Oxidoreductases; EC 1.3.-/Oxidoreductases Acting on CH-CH Group Donors; EC 1.3.1.33/protochlorophyllide reductase

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


Previous Document:  Thermal stability of different forms of diphtheria toxin.
Next Document:  On the function of cytochrome b5 in the cytochrome P-450-dependent oxygenase system.