Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2010-6-29
pubmed:abstractText
Membrane-permeable and impermeable inhibitors of carbonic anhydrase have been used to assess the roles of extracellular and intracellular carbonic anhydrase on the inorganic carbon concentrating system in Chlamydomonas reinhardtii. Acetazolamide, ethoxzolamide, and a membrane-impermeable, dextran-bound sulfonamide were potent inhibitors of extracellular carbonic anhydrase measured with intact cells. At pH 5.1, where CO(2) is the predominant species of inorganic carbon, both acetazolamide and the dextran-bound sulfonamide had no effect on the concentration of CO(2) required for the half-maximal rate of photosynthetic O(2) evolution (K(0.5)[CO(2)]) or inorganic carbon accumulation. However, a more permeable inhibitor, ethoxzolamide, inhibited CO(2) fixation but increased the accumulation of inorganic carbon as compared with untreated cells. At pH 8, the K(0.5)(CO(2)) was increased from 0.6 micromolar to about 2 to 3 micromolar with both acetazolamide and the dextran-bound sulfonamide, but to a higher value of 60 micromolar with ethoxzolamide. These results are consistent with the hypothesis that CO(2) is the species of inorganic carbon which crosses the plasmalemma and that extracellular carbonic anhydrase is required to replenish CO(2) from HCO(3) (-) at high pH. These data also implicate a role for intracellular carbonic anhydrase in the inorganic carbon accumulating system, and indicate that both acetazolamide and the dextran-bound sulfonamide inhibit only the extracellular enzyme. It is suggested that HCO(3) (-) transport for internal accumulation might occur at the level of the chloroplast envelope.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/16664365-16590601, http://linkedlifedata.com/resource/pubmed/commentcorrection/16664365-16659972, http://linkedlifedata.com/resource/pubmed/commentcorrection/16664365-16661446, http://linkedlifedata.com/resource/pubmed/commentcorrection/16664365-16661652, http://linkedlifedata.com/resource/pubmed/commentcorrection/16664365-16661792, http://linkedlifedata.com/resource/pubmed/commentcorrection/16664365-16663123, http://linkedlifedata.com/resource/pubmed/commentcorrection/16664365-16663206, http://linkedlifedata.com/resource/pubmed/commentcorrection/16664365-16663867, http://linkedlifedata.com/resource/pubmed/commentcorrection/16664365-16664038, http://linkedlifedata.com/resource/pubmed/commentcorrection/16664365-31766, http://linkedlifedata.com/resource/pubmed/commentcorrection/16664365-408462, http://linkedlifedata.com/resource/pubmed/commentcorrection/16664365-4309258, http://linkedlifedata.com/resource/pubmed/commentcorrection/16664365-4967586, http://linkedlifedata.com/resource/pubmed/commentcorrection/16664365-6430195, http://linkedlifedata.com/resource/pubmed/commentcorrection/16664365-7264948
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Sep
pubmed:issn
0032-0889
pubmed:author
pubmed:issnType
Print
pubmed:volume
79
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
177-83
pubmed:dateRevised
2010-9-14
pubmed:year
1985
pubmed:articleTitle
Effect of Carbonic Anhydrase Inhibitors on Inorganic Carbon Accumulation by Chlamydomonas reinhardtii.
pubmed:affiliation
Department of Biochemistry, Michigan State University, East Lansing, Michigan 48824.
pubmed:publicationType
Journal Article