Regioisomer separation and identification of triacylglycerols containing vaccenic and oleic acids, and α- and γ-linolenic acids, in thermophilic cyanobacteria Mastigocladus laminosus and Tolypothrix sp.

The reversible photochemistry of theα-subunit of phycoerythrocyanin (α-PEC) has been measured by low temperature absorption and circular dichroism in the range of 125K to 295 K. Below 185 K, the photochemistry is nearly silent; above 205 K, the photochemistry increases gradually without an indication of intermediates, and between 185 to 205K spectral changes in absorption and circular dichroism indicate an intermediate and/or changes in the interaction(s) between the chromophore and its environment.

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Morphology and ultrastructure of the cyanobacterium Mastigocladus laminosus growing under nitrogen-fixing conditions

Archives of Microbiology ◽

10.1007/bf00414447 ◽

1984 ◽

Vol 137 (2) ◽

pp. 97-103 ◽

Cited By ~ 8

Author(s):

S. A. Nierzwicki-Bauer ◽

D. L. Balkwill ◽

S. E. Stevens

Keyword(s):

Nitrogen Fixing ◽

Mastigocladus Laminosus

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C-Phycocyanin from Mastigocladus laminosus. Isolation and Properties of Subunits and, Small Aggregates

Antennas and Reaction Centers of Photosynthetic Bacteria - Springer Series in Chemical Physics ◽

10.1007/978-3-642-82688-7_3 ◽

1985 ◽

pp. 17-25 ◽

Cited By ~ 6

Author(s):

W. John ◽

R. Fischer ◽

S. Siebzehnrübl ◽

H. Scheer

Keyword(s):

Mastigocladus Laminosus

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Probing Functional Diversity of Thermophilic Cyanobacteria in Microbial Mats

Functional Genomics and Evolution of Photosynthetic Systems - Advances in Photosynthesis and Respiration ◽

10.1007/978-94-007-1533-2_2 ◽

2011 ◽

pp. 17-46 ◽

Cited By ~ 2

Author(s):

Devaki Bhaya

Keyword(s):

Functional Diversity ◽

Microbial Mats ◽

Thermophilic Cyanobacteria

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Electron Transport from QA to Thymoquinone in a Synechococcus Oxygen-Evolving Photosystem II Preparation: Role of QB and Binding Affinity of Thymoquinone to the QB Site

Zeitschrift für Naturforschung C ◽

10.1515/znc-1993-3-411 ◽

1993 ◽

Vol 48 (3-4) ◽

pp. 174-178 ◽

Cited By ~ 1

Author(s):

Kazuhiko Satoh ◽

Yasuhiro Kashino ◽

Hiroyuki Koike

Keyword(s):

Binding Affinity ◽

Turnover Rate ◽

Side Chain ◽

Head Group ◽

Binding Affinities ◽

Ps Ii ◽

Thermophilic Cyanobacteria ◽

High Concentrations ◽

Oxygen Evolving

Abstract We have recently shown that binding affinities of benzoquinones can be estimated by two methods in photosystem (PS) II particles (K. Satoh et al., Biochim. Biophys. Acta 1102, 45-52 (1992)). Using these methods we calculated the binding affinity of thymoquinone (2-methyl-5-isopropyl-p-benzoquinone) to the QB site and studied how the quinone accepts electrons in oxygen-evolving PS II particles isolated from the thermophilic cyanobacteria, Synechococcus elongatus and S. vulcanus. The results are as follows: (1) The binding constant of thymoqui none to the QB site determined by several methods was around 0.33 mᴍ . (2) At low thymoquinone concentrations the quinone was supposed to accept electrons via QB-plastoquinone, whereas at high concentrations the quinone seemed to bind to the QB site and accept an electron directly from Q-A. Lower rates of photoreduction of the quinone at high concentrations were attributed to a slower turnover rate of the quinone at the QB site than that of endogenous plastoquinone. (3) A model for the function of plastoquinone at the QB site, which can explain all the results, was presented. According to this model, the plastoquinone molecule at the QB site is not replaced by another plastoquinone molecule. Instead, it transfers electrons to pool plastoquinone molecules by turning over its head group but remaining its long side chain bound to the PS II complexes.

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Chromophore Assignment in C-Phycocyanin from Mastigocladus laminosus

Zeitschrift für Naturforschung C ◽

10.1515/znc-1987-0315 ◽

1987 ◽

Vol 42 (3) ◽

pp. 258-262 ◽

Cited By ~ 31

Author(s):

S. Siebzehnrübl ◽

R. Fischer ◽

H. Scheer

Keyword(s):

Circular Dichroism ◽

Binding Sites ◽

Specific Binding ◽

Reactive Site ◽

Spectral Changes ◽

Mastigocladus Laminosus ◽

Specific Binding Sites ◽

Close Proximity ◽

Circular Dichroïsm ◽

Unambiguous Assignment

C-phycocyanin from the cyanobacterium, Mastigocladus laminosus, and its subunits have been treated with ρ-chloromercuribenzenesulfonate (PCMS). A single reactive site was found on the 13- subunit, and assigned to the single free cystein-β109. The concomitant spectral changes (absorption, fluorescence, circular dichroism), together with the known close proximity of cys-β109 to chromophore β82, allowed an unambiguous assignment of the three spectrally, biochemically and functionally different chromophores to specific binding sites on the two peptide chains (α84: 616-618, β82: 622-624, β153: 598-600 nm).

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