Document Detail

The role of dark carbon dioxide fixation in root nodules of soybean.
MedLine Citation:
PMID:  16664774     Owner:  NLM     Status:  PubMed-not-MEDLINE    
The magnitude and role of dark CO(2) fixation were examined in nodules of intact soybean plants (Harosoy 63 x Rhizobium japonicum strain USDA 16). The estimated rate of nodule dark CO(2) fixation, based on a 2 minute pulse-feed with (14)CO(2) under saturating conditions, was 102 micromoles per gram dry weight per hour. This was equivalent to 14% of net nodule respiration. Only 18% of this CO(2) fixation was estimated to be required for organic and amino acid synthesis for growth and export processes. The major portion (75-92%) of fixed label was released as CO(2) within 60 minutes. The labeling pattern during pulse-chase experiments was consistent with CO(2) fixation by phosphoenolpyruvate carboxylase. During the chase, the greatest loss of label occurred in organic acids. Exposure of nodulated roots to Ar:O(2) (80:20) did not affect dark CO(2) fixation, while exposure to O(2):CO(2) (95:5) resulted in 54% inhibition. From these results, it was concluded that at least 66% of dark CO(2) fixation in soybean may be involved with the production of organic acids, which when oxidized would be capable of providing at least 48% of the requirement for ATP equivalents to support nitrogenase activity.
B J King; D B Layzell; D T Canvin
Related Documents :
22067044 - Effect of vehicle systems, ph and enhancers on the permeation of highly lipophilic arip...
22008254 - Actinoplanes teichomyceticus atcc 31121 as a cell factory for producing teicoplanin.
25174674 - Physico-chemical characteristics of papaya (carica papaya l.) seed oil of the hong kong...
21807504 - Dilute-sulfuric acid pretreatment of cattails for cellulose conversion.
24995364 - Hydrogen peroxide is involved in salicylic acid-elicited rosmarinic acid production in ...
20416834 - Fatty acid profile of hind leg muscle in female and male nutria (myocastor coypus mol.)...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Plant physiology     Volume:  81     ISSN:  0032-0889     ISO Abbreviation:  Plant Physiol.     Publication Date:  1986 May 
Date Detail:
Created Date:  2010-06-29     Completed Date:  2010-06-29     Revised Date:  2010-09-14    
Medline Journal Info:
Nlm Unique ID:  0401224     Medline TA:  Plant Physiol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  200-5     Citation Subset:  -    
Department of Biology, Queen's University, Kingston, Ontario K7L 3N6 Canada.
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:  Biosynthetic Cause of in Vivo Acquired Thermotolerance of Photosynthetic Light Reactions and Metabol...
Next Document:  Oligosaccharide Side Chains of Glycoproteins that Remain in the High-Mannose Form Are Not Accessible...