Linked Life Data

16658271

Source:http://linkedlifedata.com/resource/pubmed/id/16658271

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2010-6-29
pubmed:abstractText
In the evolution of the absorption spectrum of etiolated bean leaves (Phaseolus vulgaris L.) following illumination, a rapid photoconversion of 50% or more of the active protochlorophyllide at room temperature is followed by a shift of the chlorophyll(ide) absorption maximum: C(678)--> -->C(684)-->C(672 nm). Kinetic studies at 2 C and the absence of an isosbestic point provide evidence for an intermediate between C(678) and C(684). A dramatically different evolution is observed following the photoconversion of only 5 to 30% of the active protochlorophyllide at room temperature. C(672) appears within 30 seconds, and no subsequent dark shift occurs during the following 90 minutes. At 0 C, conversion of 5% of the active protochlorophyllide produces a new species, C(676), which converts progressively to C(672) within 10 minutes. We interpret the results in terms of two photochemical steps operating in series for the complete conversion of active protochlorophyllide. Furthermore, there appears to be competition between an irreversible, terminal dark shift and the second light reaction. We propose a scheme based on dimers of protochlorophyllide reduced stepwise to dimers of chlorophyllide in two successive light reactions. The intermediate mixed protochlorophyllide-chlorophyllide dimer absorbs at 676 nm and displays a much faster dissociation to monomers than does the chlorophyllide-chlorophyllide dimer.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Jan
pubmed:issn
0032-0889
pubmed:author
pubmed:issnType
Print
pubmed:volume
51
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
115-9
pubmed:dateRevised
2010-9-14
pubmed:year
1973
pubmed:articleTitle
Chlorophyll Formation in Greening Bean Leaves during the Early Stages.
pubmed:affiliation
Department of Chemistry and Laboratory of Chemical Biodynamics, Lawrence Berkeley Laboratory, University of California, Berkeley, California 94720.
pubmed:publicationType
Journal Article