Coral bleaching events have become more frequent and widespread, largely due to elevated sea surface temperatures. Global climate change could lead to increased variability of sea surface temperatures, through influences on climate systems, e.g. El Niño Southern Oscillation (ENSO). Field observations in 1999, following a strong ENSO, revealed that corals bleached in winter after unusually cold ...

A high performance liquid chromatography (HPLC) system for pigment analysis of marine phytoplankton was established. The characteristic quantification limits of the major photosynthetic chlorophylls a and b were 0.29 and 0.27 ng, respectively. The reliability of this method was verified by resolving the marker pigments in culture extracts from diatoms, blue-green algae and green algae. Fucoxant...

Recent in vitro studies have led to speculation that a novel light-harvesting protochlorophyllide a/b-binding protein complex (LHPP) might exist in dark-grown angiosperms. Structurally, it has been suggested that LHPP consists of a 5:1 ratio of dark-stable ternary complexes of the light-dependent NADPH: protochlorophyllide oxidoreductases A and B containing nonphotoactive protochlorophyllide b ...

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...

Intracellular calcification of coccolithophores generates CO₂ and consumes additional energy for acquisition of calcium and bicarbonate ions; therefore, it may correlate with photoprotective processes by influencing the energetics. To address this hypothesis, a calcifying Emiliania huxleyi strain (CS-369) was grown semi-continuously at reduced (0.1 mM, LCa) and ambient Ca²⁺ concentrations (10 m...

The photosystem I reaction center complex, the P-700-chlorophyll a-protein, has been isolated from the photosynthetic membranes of two marine dinoflagellates, Gonyaulax polyedra and Glenodinium sp., by detergent solubilization with Triton X-100. The complexes isolated from the two species were indistinguishable, exhibiting identical absorption properties (400-700 nm) at both room (300 K) and lo...

Responses of the photosynthetic activity of Phaeodactylum tricornutum (Bacillariophyta) to organic carbon glycerol were investigated. The growth rate, photosynthetic pigments, 77 K fluorescence spectra, and chloroplast ultrastructure of P. tricornutum were examined under photoautotrophic, mixotrophic, and photoheterotrophic conditions. The results showed that the specific growth rate was the fa...

The light-harvesting complex I (LH-I) of Rhodobacter sphaeroides has been modeled computationally as a hexadecamer of alphabeta-heterodimers, based on a close homology of the heterodimer to that of light-harvesting complex II (LH-II) of Rhodospirillum molischianum. The resulting LH-I structure yields an electron density projection map that is in agreement with an 8.5-A resolution electron micro...

Reaction centres are membrane-embedded pigment-protein complexes that transduce the energy of sunlight into a biologically useful form. The most heavily studied reaction centres are the PS-I (Photosystem I) and PS-II complexes from oxygenic phototrophs, and the reaction centre from purple photosynthetic bacteria. A great deal is known about the compositions and structures of these reaction cent...