Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2010-6-29
pubmed:abstractText
Mesophyll cells and bundle sheath strands isolated from leaves of the C(4) plant Digitaria sanguinalis (L.) Scop. are capable of utilizing aspartate as a Hill oxidant. The resulting O(2) evolution upon illumination depends on the presence of 2-oxoglutarate, is inhibited by 3-(3,4-dichlorophenyl)-1,1-dimethylurea, and is stimulated by methylamine. The rate of aspartate-dependent O(2) evolution with mesophyll cells was similar to those with phosphoenolpyruvate + CO(2) or with oxalacetate. Amino-oxyacetate, an inhibitor of aspartate aminotransferase, inhibited the aspartate-dependent O(2) evolution. Aspartate aminotransferase and NADP(+) -malate dehydrogenase are located in the mesophyll chloroplasts. These data suggest that aspartate is converted to oxalacetate via aspartate aminotransferase in the chloroplasts of mesophyll cells and that oxalacetate is subsequently reduced to malate, which is coupled to the photochemical evolution of O(2). This suggestion is further verified by the inhibition of phosphoenolpyruvate-dependent (14)CO(2) fixation by aspartate + 2-oxoglutarate, which presumably acts as oxalacetate and competes with phosphoenolpyruvate + CO(2) for NADPH. dl-Glyceraldehyde inhibited aspartate-dependent O(2) evolution in the bundle sheath strands but not in the mesophyll cells. The data indicate that aspartate may be converted to malate in both mesophyll and bundle sheath cells. In NADP(+) -malic enzyme species, aspartate may exist as a C(4)-dicarboxylic acid reservoir which can contribute to the C(4) cycle through its conversion to malate.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/16662295-16592125, http://linkedlifedata.com/resource/pubmed/commentcorrection/16662295-16657571, http://linkedlifedata.com/resource/pubmed/commentcorrection/16662295-16658252, http://linkedlifedata.com/resource/pubmed/commentcorrection/16662295-16659177, http://linkedlifedata.com/resource/pubmed/commentcorrection/16662295-16659295, http://linkedlifedata.com/resource/pubmed/commentcorrection/16662295-16659330, http://linkedlifedata.com/resource/pubmed/commentcorrection/16662295-16659590, http://linkedlifedata.com/resource/pubmed/commentcorrection/16662295-16660092, http://linkedlifedata.com/resource/pubmed/commentcorrection/16662295-16660955, http://linkedlifedata.com/resource/pubmed/commentcorrection/16662295-435326, http://linkedlifedata.com/resource/pubmed/commentcorrection/16662295-4571408, http://linkedlifedata.com/resource/pubmed/commentcorrection/16662295-4643699, http://linkedlifedata.com/resource/pubmed/commentcorrection/16662295-4730470, http://linkedlifedata.com/resource/pubmed/commentcorrection/16662295-5421941, http://linkedlifedata.com/resource/pubmed/commentcorrection/16662295-5867546, http://linkedlifedata.com/resource/pubmed/commentcorrection/16662295-883824
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Apr
pubmed:issn
0032-0889
pubmed:author
pubmed:issnType
Print
pubmed:volume
69
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
776-80
pubmed:dateRevised
2010-9-14
pubmed:year
1982
pubmed:articleTitle
Photosynthetic Metabolism of Aspartate in Mesophyll and Bundle Sheath Cells Isolated from Digitaria sanguinalis (L.) Scop., a NADP-Malic Enzyme C(4) Plant.
pubmed:affiliation
Department of Biochemistry, University of Georgia, Athens, Georgia 30602.
pubmed:publicationType
Journal Article