The present work uses a scanning electrochemical microscopy technique to study systems containing the membrane-bound reaction center protein (RC) from the purple photosynthetic bacteria Rhodobacter spheroides to chromatophores (spherical reorganization of cell membrane following its mechanical rupture) and liposomes (reconstituted membrane systems at lower degree of complexity). Scanning electr...

Alterations in membrane structure as a result of lipid phase transitions have been studied in Anacystis nidulans, a blue-green alga. Cells grown at 38 degrees C were subjected to temperature transitions of 38 degrees C leads to 21 degrees C and 38 degrees C leads to 10 degrees C, previously shown to produce substantial changes in photosynthetic activities, and examined by freeze-fracture electr...

Almost all life on earth is dependent on sun as the ultimate energy source, but only a limited number of living organisms are able to use energy directly from the sun in a process called photosynthesis. Photosynthesis is a process where organisms like plants, algae, cyanobacteria and photosynthetic bacteria absorb and use light to convert simple molecules like carbon dioxide and water into more...

Import of nuclear-encoded precursor proteins from the cytosol is an essential step in chloroplast biogenesis that is mediated by protein translocon complexes at the inner and outer envelope membrane (TOC). Toc159 is thought to be the main receptor for photosynthetic proteins, but lacking a large-scale systems approach, this hypothesis has only been tested for a handful of photosynthetic and non...

The import of nucleus-encoded proteins into chloroplasts is mediated by translocon complexes in the envelope membranes. A component of the translocon in the outer envelope membrane, Toc34, is encoded in Arabidopsis by two homologous genes, atTOC33 and atTOC34. Whereas atTOC34 displays relatively uniform expression throughout development, atTOC33 is strongly upregulated in rapidly growing, photo...

nineteen bread wheat genotypes were selected to examine the effect of glycine betaine (gb, 100 mm) on various photosynthetic gas exchange parameters under drought stress and to study the relationship of these parameters with non-enzymatic antioxidants. drought stress caused a significant decline in net co2 assimilation rate (pn), stomatal conductance (gs), intercellular co2 concentration (ci) a...

Potassium (K + ) exerts key physiological functions such as osmoregulation, stomatal movement, membrane transport, protein synthesis and photosynthesis among others. Previously, it was demonstrated in Arabidopsis thaliana that the loss of function chloroplast K E fflux A ntiporters KEA1 KEA2, located inner envelope membrane, provokes inefficient photosynthesis. Therefore, main goal this study t...

Z. Naturforsch. 44c, 959—965 (1989); received April 19, 1989 ß-Carotene-5,6-epoxide, Photooxidation, DCMU, Carotenoids The occurrence of ß-carotene-5,6-epoxide in higher plant photosynthetic tissue is described. The compound is found in isolated chloroplasts, thylakoids and other subchloroplast particles but can only be detected in intact leaves or cotyledons of higher plants when these are exp...