Isolation and Identification of Algicidal Compound from Streptomyces and Algicidal Mechanism to Microcystis aeruginosa

The fast-death factor in Microcystis aeruginosa NRC-1 is an acidic, probably cyclic peptide containing the following amino acids in the molar ratios indicated: L-aspartic (1); L-glutamic (2); D-serine (1); L-valine (1); L-ornithine (1); L-alanine (2); L-leucine (2). It is possible, although not likely, that one of the residues of glutamic, alanine, or leucine also is in the D-configuration. The toxin, in the form of its sodium salt, was extracted from lyophilized algal cells by water, separated from pigments by extraction into n-butanol, and freed from high-molecular-weight impurities by dialysis. No separation of a single toxic compound could be obtained by countercurrent distribution, chromatography, or electrophoresis in carbonate, acetate, or phosphate buffers. Electrophoresis of the crude toxin on cellulose in 0.1 M borate yielded five peptides one of which was toxic and accounted for 100% of the toxicity present in the crude preparation. The intraperitoneal LD50of the pure toxin for mice was 0.466 ± 0.013 mg/kg body weight.

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Isolation and Identification of Two Algae-Lysing Bacteria against Microcystis aeruginosa

Water ◽

10.3390/w12092485 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2485

Author(s):

Jing Yang ◽

Kai Qiao ◽

Junping Lv ◽

Qi Liu ◽

Fangru Nan ◽

...

Keyword(s):

Microcystis Aeruginosa ◽

Harmful Algal Blooms ◽

Algal Blooms ◽

Removal Rate ◽

Polymerase Chain Reaction Amplification ◽

Cyanobacterial Bloom ◽

Practical Significance ◽

Algicidal Bacteria ◽

Bacterial Strains ◽

Isolation And Identification

Algae blooms present an environmental problem worldwide. In response to the outbreak of harmful algal blooms in cyanobacteria, the role of biological control has drawn wide attention, particularly for algicidal bacteria. The mechanism underlying algicidal activity was determined in our study. Algae-lysing bacteria used were separated from water and sediment collected from the Fenhe scenic spot of Taiyuan. Genetic and molecular identification was conducted by polymerase chain reaction amplification based on 16S rDNA gene. These bacterial strains were identified as Raoultella planticola and Aeromonas sp. The algae-lysing characteristics were evaluated on Microcystis aeruginosa. For the two algicidal bacteria, the high inoculation ratio (>8%) of bacteria strains contributed to the lytic effect. M. aeruginosa could be completely removed by these strains at different cell ages. However, the time used decreased with an increase in cell age. The removal rate was increased while M. aeruginosa was in the lag and logarithmic phases. The earlier bacteria strains could be inoculated, the sooner all algae could be removed. Both algicidal substances were protein, which could destroy the photosynthetic systems and break the cell of M. aeruginosa. The algicidal bacteria strain has important theoretical and practical significance for economic and feasible algae removal and provides good germplasm resources and technical support for the control of cyanobacterial bloom.

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ISOLATION AND IDENTIFICATION OF THE FAST-DEATH FACTOR IN MICROCYSTIS AERUGINOSA NRC-1

Canadian Journal of Biochemistry and Physiology ◽

10.1139/o59-047 ◽

1959 ◽

Vol 37 (3) ◽

pp. 453-471 ◽

Cited By ~ 91

Author(s):

C. T. Bishop ◽

E. F. L. J. Anet ◽

P. R. Gorham

Keyword(s):

Amino Acids ◽

Molecular Weight ◽

Body Weight ◽

Microcystis Aeruginosa ◽

Sodium Salt ◽

Cyclic Peptide ◽

Isolation And Identification ◽

Toxic Compound ◽

Molar Ratios ◽

Crude Preparation

The fast-death factor in Microcystis aeruginosa NRC-1 is an acidic, probably cyclic peptide containing the following amino acids in the molar ratios indicated: L-aspartic (1); L-glutamic (2); D-serine (1); L-valine (1); L-ornithine (1); L-alanine (2); L-leucine (2). It is possible, although not likely, that one of the residues of glutamic, alanine, or leucine also is in the D-configuration. The toxin, in the form of its sodium salt, was extracted from lyophilized algal cells by water, separated from pigments by extraction into n-butanol, and freed from high-molecular-weight impurities by dialysis. No separation of a single toxic compound could be obtained by countercurrent distribution, chromatography, or electrophoresis in carbonate, acetate, or phosphate buffers. Electrophoresis of the crude toxin on cellulose in 0.1 M borate yielded five peptides one of which was toxic and accounted for 100% of the toxicity present in the crude preparation. The intraperitoneal LD50of the pure toxin for mice was 0.466 ± 0.013 mg/kg body weight.

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