Effects of amino acids on the blue-green alga (cyanobacteria) Tolypothrix scytonemoides (Gardner) Geitler

A cell-free preparation of the blue-green alga, Anabaena variabilis, that incorporates 14C-labelled amino acids into protein has been prepared and characterized. The activation of amino acids to amino acid transfer RNAs was characterized, and assembly of these into peptides has been described with respect to cofactor requirements and antibiotic sensitivity. The properties of these systems and the effect of antibiotics on them are similar to those of bacteria. Both natural and synthetic messenger RNA were effective in peptide formation. The kinetics of incorporation of [14C]uracil into RNA has been examined and the stability of labelled RNA from A. variabilis measured by radioactivity loss and by its role in directing peptide synthesis. The half-life of messenger RNA from this organism is approximately 12 min, and as such is comparable to that of bacteria when based upon the mean generation time of the respective organisms.

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A new isolation and structure for the endotoxin from Microcystis aeruginosa NRC-1

Canadian Journal of Biochemistry ◽

10.1139/o70-081 ◽

1970 ◽

Vol 48 (4) ◽

pp. 508-510 ◽

Cited By ~ 32

Author(s):

J. Rama Murthy ◽

J. B. Capindale

Keyword(s):

Amino Acids ◽

Body Weight ◽

Solvent Extraction ◽

Microcystis Aeruginosa ◽

Green Alga ◽

Complex Structure ◽

Strain Analysis ◽

Blue Green Alga ◽

Algal Strain ◽

Toxic Material

The endotoxin from the blue–green alga Microcystis aeruginosa NRC-1 has been isolated as its ammonium salt by a new procedure involving solvent extraction and elution from DEAE-Sephadex A-25. The intraperitoneal LD100 of this toxin preparation for mice was 0.1 mg/kg body weight. The product is a white solid which appears to be chromatographically and electrophoretically homogeneous. This toxin produces similar symptoms in mice to those described originally for the toxic material from the same algal strain. Analysis of the toxin hydrolysate indicates a more complex structure since seven more amino acids have been found, including tyrosine, proline, and arginine, in addition to the seven reported before.

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Production of amino acids by the N2-fixing blue-green alga Anabaena variabilis var. kashiensis

Zentralblatt für Mikrobiologie ◽

10.1016/s0232-4393(85)80048-2 ◽

1985 ◽

Vol 140 (4) ◽

pp. 333-339

Author(s):

A.A. El-Essawy ◽

E.Y. El-Ayouty ◽

Y.M. El-Ayouty

Keyword(s):

Amino Acids ◽

Green Alga ◽

Anabaena Variabilis ◽

Blue Green Alga

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Effect of Iron Limitation on the Ultrastructure of Agmenellum Quadruplicatum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100098551 ◽

1981 ◽

Vol 39 ◽

pp. 410-411

Author(s):

L. P. Hardie ◽

D. L. Balkwill ◽

S. E. Stevens

Keyword(s):

Growth Medium ◽

Green Alga ◽

Natural Habitat ◽

Iron Limitation ◽

Natural Environments ◽

Blue Green Alga ◽

Marine Cyanobacterium ◽

Natural Systems ◽

Thin Sectioning ◽

Agmenellum Quadruplicatum

Agmenellum quadruplicatum is a unicellular, non-nitrogen-fixing, marine cyanobacterium (blue-green alga). The ultrastructure of this organism, when grown in the laboratory with all necessary nutrients, has been characterized thoroughly. In contrast, little is known of its ultrastructure in the specific nutrient-limiting conditions typical of its natural habitat. Iron is one of the nutrients likely to limit this organism in such natural environments. It is also of great importance metabolically, being required for both photosynthesis and assimilation of nitrate. The purpose of this study was to assess the effects (if any) of iron limitation on the ultrastructure of A. quadruplicatum. It was part of a broader endeavor to elucidate the ultrastructure of cyanobacteria in natural systemsActively growing cells were placed in a growth medium containing 1% of its usual iron. The cultures were then sampled periodically for 10 days and prepared for thin sectioning TEM to assess the effects of iron limitation.

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