Changes in the absorption spectra o f P. cruentum and phycobiliprotein are observed as a function o f hydrostatic pressure. With phycobiliprotein both in solution and in algae, increasing hydrostatic pressure results in bathochromic shifts o f the absorption maxima. In addition, there is a splitting o f the absorption band of phycoerythrin. When P. cruentum is subjected to 250 bars there are in...

Nitrogenase activity was measured in leaves along the main stem axes of Azolla pinnata R. Br. The activity was negligible in leaves of the apical region, rapidly increased to a maximum as leaves matured, and declined in aging leaves. In situ absorption and fluorescence emission spectra were obtained for individual vegetative cells and heterocysts in filaments of the A. pinnata and Azolla caroli...

Antibodies raised against mixtures of phycobilisome polypeptides from the eukaryotic alga Cyanidium caldarium were used in an immunological screen to detect expression of phycobiliprotein genes in an Escherichia coli library containing segments of plastid (chloroplast, cyanelle) DNA from another eukaryotic alga, Cyanophora paradoxa. The four candidate clones obtained were mapped by restriction ...

The synthesis of a novel class of reagents for fluorescence analyses of molecules and cells is reported. These compounds consist of a highly fluorescent phycobiliprotein conjugated to a molecule having biological specificity. Phycoerythrin-immunoglobulin, phycoerythrin-protein A, and phycoerythrin-avidin conjugates were prepared. These conjugates bind specifically to beads containing a covalent...

Physiological aspects of salt-adaptation in the cyanobacterium Synechococcus 6311 growing in a continuous culture (turbidostat) were studied. The process of salt-adaptation was completed within 3 days, as expressed by the specific growth rate of cells grown in the presence of 0.2 and 0.4 molar NaCl. An increase in photosynthetic activity during the adaptation period leads to the accumulation of...

The peptides were examined by lH NMR, circular dichroism spectroscopy, and secondary ion mass spectrometry. The ‘H NMR data confirmed that in each case the bilin was attached through a single linkage, a thioether bond between the cysteinyl residue and the tetrapyrrole moiety. Comparison of the ’H NMR spectra of these peptides with those of appropriate model compounds showed that the thioether l...

Present research was to evaluate and compare the antiradical and antioxidant activities of extracts from Spirulina platensis. In the present study, three extracts (Water, absolute methanol and 50% methanol in water) were analyzed for the total phenolic compounds, phycobiliprotein content: Antiradical and antioxidant activities were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-az...

Photosynthesis, Assimilates, Chemotaxonomy, Phycobiliprotein-Containing Algae Representatives o f phycobiliprotein-containing algae such as Anabaena cylindrica, Anacystis nidulans, Gloeotrichia echinulata (Cyanophyceae), Chroomonas spec., Hemiselmis rufescens, Rhodomonas spec. (Cryptophyceae), Porphyridium cruentum, Rhodella violacea (Rhodophyceae) along with the unicellular Cyanidium caldarium...

Microcystis aeruginosa, a unicellular cyanobacterium, contains small phycobilisomes consisting of C-phycocyanin, allophycocyanin, and linker polypeptides. SDS-polyacrylamide gels of the phycobilisomes were examined for fluorescent bands before and after spraying with a solution of ZnSO(4), followed by Coomassie brilliant blue staining for protein. This procedure provides a rapid and sensitive m...