Document Detail

Ethylene metabolism in Scots pine (Pinus sylvestris) shoots during the year.
MedLine Citation:
PMID:  11772556     Owner:  NLM     Status:  MEDLINE    
Ethylene evolution, concentrations of 1-aminocyclopropane-1-carboxylic acid (ACC) and ACC conjugates, activities of ACC synthase and ACC oxidase, and cambial growth as measured by tracheid production were monitored from November to July in 1-year-old shoots, and between July and September in current-year shoots, of Scots pine (Pinus sylvestris L.). Needles, buds and four stem parts (cortex, phloem, cambial region and mature xylem) were surveyed. Ethylene evolution was quantified by gas chromatography. Free ACC and bound ACC (after acidic hydrolysis of ACC conjugates) were quantified by combined gas chromatography-mass spectrometry, with [2H]ACC as an internal standard. Activities of ACC synthase and ACC oxidase were measured in crude protein extracts. We detected high activities of ACC synthase in needles and buds, but not in stem fractions except the phloem. In July, during the period of intensive shoot growth, we found ACC only in buds and needles. In contrast, ACC oxidase activity was high in stem tissues, particularly in the cambial region during the period of rapid tracheid production, but no ACC oxidase activity was detected in needles and buds. Nevertheless, needles evolved large amounts of ethylene. Ethylene was produced by all stem fractions, and the peak rate of ethylene evolution in the cambial region coincided with the period of maximal tracheid production. Conjugated ACC was present in every fraction except mature xylem. The concentration of conjugated ACC decreased when rates of tracheid production and ethylene evolution were high, suggesting that conjugated ACC may serve as a source for ACC in the cambial region. The regulation of ethylene biosynthesis in Scots pine shoots is discussed.
Alla Klintborg; Leif Eklund; C H Anthony Little
Related Documents :
14580796 - Catabolism of volatile sulfur compounds precursors by brevibacterium linens and geotric...
6141136 - Enzymatic determination of several d-amino acids using luminol-mediated chemiluminescence.
2366876 - Modulation by drugs of the release of total tritium and 3h-5-ht from rat hypothalamic s...
18709446 - Investigation of carbon nanofibers as support for bioactive substances.
9567366 - Histochemical staining of bone aluminum: comparison of aluminon and acid solochrome azu...
256546 - Principal substrates of fetal metabolism: fuel and growth requirements of the ovine fetus.
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Tree physiology     Volume:  22     ISSN:  0829-318X     ISO Abbreviation:  Tree Physiol.     Publication Date:  2002 Jan 
Date Detail:
Created Date:  2002-01-04     Completed Date:  2002-09-17     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  100955338     Medline TA:  Tree Physiol     Country:  Canada    
Other Details:
Languages:  eng     Pagination:  59-66     Citation Subset:  IM    
School of Biosciences and Process Technology, Växjö University, S-351 95 Växjö, Sweden.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Amino Acid Oxidoreductases / metabolism
Amino Acids, Cyclic / analysis
Ethylenes / biosynthesis,  metabolism*
Lyases / metabolism
Pinus / chemistry,  metabolism,  physiology*
Pinus sylvestris
Plant Leaves / chemistry
Plant Shoots / chemistry,  enzymology,  metabolism*
Plant Stems / chemistry
Reg. No./Substance:
0/Amino Acids, Cyclic; 0/Ethylenes; 22059-21-8/1-aminocyclopropane-1-carboxylic acid; 74-85-1/ethylene; EC 1.4.-/Amino Acid Oxidoreductases; EC 1.4.3.-/1-aminocyclopropane-1-carboxylic acid oxidase; EC 4.-/Lyases; EC synthase

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

Previous Document:  Annual shoot growth components related to growth of Pinus brutia.
Next Document:  Measurement carbon dioxide concentration does not affect root respiration of nine tree species in th...