Photosynthetic utilization of bicarbonate in Zostera marina is reduced by inhibitors of mitochondrial ATPase and electron transport
2008 (English)In: Plant Physiology, ISSN 0032-0889, E-ISSN 1532-2548, Vol. 147, no 2, 879-885 p.Article in journal (Refereed) Published
When Zostera marina was irradiated after a period of darkness, initiation of photosynthetic O-2 evolution occurred in two phases. During a lag phase, lasting 4 to 5 min, photosynthesis was supported by a diffusive entry of CO2. Photosynthesis then rapidly increased to its full rate. Tris buffer, at a concentration of 50 mM, completely inhibited this increase without affecting CO2-supported photosynthesis during the lag phase. These results verify that the increase in photosynthesis after the lag phase depended on an activation of bicarbonate (HCO3-) utilization through acid zones generated by proton pumps located to the outer cell membrane. In similar experiments, 6.25 mu M of the mitochondrial ATPase blocker oligomycin inhibited photosynthetic HCO3- utilization by more than 60%. Antimycin A, a selective blocker of mitochondrial electron transport, caused a similar inhibition of HCO3- utilization. Measurements at elevated CO2 concentrations verified that neither oligomycin nor antimycin interfered with linear photosynthetic electron transport or with CO2 fixation. Thus, a major part of the ATP used for the generation of acid zones involved in HCO3- utilization in Z. marina was derived from mitochondrial respiration.
Place, publisher, year, edition, pages
2008. Vol. 147, no 2, 879-885 p.
inorganic carbon acquisition, co2 concentrating mechanisms, barley hordeum-vulgare, mesophyll protoplasts, oxidative-metabolism, laminaria-saccharina, uncoupling protein, plasma-membrane, chara-corallina, zmpump encodes
IdentifiersURN: urn:nbn:se:su:diva-58539DOI: 10.1104/pp.107.115584ISI: 000256423600037OAI: oai:DiVA.org:su-58539DiVA: diva2:420951
authorCount :22011-06-072011-06-032011-06-07Bibliographically approved