Blue–green algae and freshwater carbonate deposits

1978 ◽  
Vol 200 (1138) ◽  
pp. 43-61 ◽  
Keyword(s):  
Green Algae ◽  
Dry Mass ◽  
Liquid Media ◽  
Deposition Rates ◽  
Thin Sections ◽  
Blue Green Algae ◽  
Microcoleus Vaginatus ◽  
Small Crystals ◽  
Carbonate Deposits ◽  
Freshwater Carbonate

Twenty-seven contemporary freshwater carbonate deposits were investigated (26 in the British Isles and 1 in S. Australia). The blue–green algae Schizothrix calcicola and Microcoleus vaginatus occurred at 23 of the sites. The remaining sites represented areas where deposition had ceased. About 1% of the dry mass of the deposits consisted of Cyanophyta. The assimilation rates of these algae, measured by 14 CO 2 uptake, were low. It was estimated that the equilibrium change caused by CO 2 uptake due to photosynthesis could account for only 1–2% of the precipitated carbonate. Cultures of S. calcicola failed to deposit carbonates in solid and liquid media. Deposition rates varied between 0.006 and 8 mm a -1 (mean 1.2 mm a -1 ). The laminations encountered at some sites could be correlated to seasonal differences in cyanophyte growth which enabled some deposits to be dated. Thin sections revealed small crystals adhering to the muci­laginous sheaths of the algae. The transmission of light in some deposits was investigated. The algal layer corresponded to the depth to which light was attenuated to about 1% of the surface intensity.

scholarly journals ELECTRON MICROSCOPE STUDIES ON BLUE-GREEN ALGAE

1961 ◽  
Vol 9 (1) ◽  
pp. 63-80 ◽  
Author(s):  
Hans Ris ◽  
R. N. Singh
Keyword(s):  
Electron Microscope ◽  
Green Algae ◽  
Animal Cell ◽  
General Pattern ◽  
The Other ◽  
Thin Sections ◽  
Double Membrane ◽  
Photosynthetic Membranes ◽  
Blue Green Algae ◽  
Developmental States

Several species of blue-green algae were studied in thin sections with the electron microscope. Our electron micrographs confirm the view that the cell of blue-green algae is different and simpler in organization than the typical plant or animal cell. On the other hand, the general pattern of ultrastructure is the same as that found in bacteria and Streptomyces. The cell boundary is formed by a double membrane which consists of two typical unit membranes. Situated in between these membranes is the dense inner investment or wall which continues uninterrupted into the cross-walls. The cells always contain photosynthetic lamellae, nucleoplasm with DNA, small granules resembling ribosomes, and often also a number of larger granules of various sorts. The photosynthetic membranes either form the boundary of vesicles or flattened sacs, or, when the lumen of the vesicles disappears and the vesicular surfaces of the membranes zip together, they appear as lamellae made of two closely applied unit membranes. These vesicles or lamellae are disposed irregularly through the cell or arranged in parallel stacks of two or more. A thin layer of cytoplasm always separates the lamellae. The nucleoplasm is composed of masses of fine fibrils about 25 A thick and is either dispersed through the cell or concentrated in polymorphous reticular structures near the center of the cell. The improved resolution of the electron microscope makes it obvious that the terms "chromatoplasm" and "centroplasm" commonly used in the description of blue-green algae are really misleading. There are not different kinds of cytoplasm, but the cell consists of various structural (and functional) units like the ones mentioned above, which are arranged in the cell in a number of ways characteristic for each species or for different physiological or developmental states.

Freeze-Fracture Replication in the Ultrastructure of Blue-Green Algae

1967 ◽  
Vol 25 ◽  
pp. 74-75
Author(s):  
L. V. Leak
Keyword(s):  
Cell Wall ◽  
Electron Microscope ◽  
Green Algae ◽  
Three Dimensional ◽  
Freeze Fracture ◽  
Electron Microscopic ◽  
Photosynthetic Membranes ◽  
Blue Green Algae ◽  
Cell Biol ◽  
Cellular Components

Electron microscopic observations of freeze-fracture replicas of Anabaena cells obtained by the procedures described by Bullivant and Ames (J. Cell Biol., 1966) indicate that the frozen cells are fractured in many different planes. This fracturing or cleaving along various planes allows one to gain a three dimensional relation of the cellular components as a result of such a manipulation. When replicas that are obtained by the freeze-fracture method are observed in the electron microscope, cross fractures of the cell wall and membranes that comprise the photosynthetic lamellae are apparent as demonstrated in Figures 1 & 2.A large portion of the Anabaena cell is composed of undulating layers of cytoplasm that are bounded by unit membranes that comprise the photosynthetic membranes. The adjoining layers of cytoplasm are closely apposed to each other to form the photosynthetic lamellae. Occassionally the adjacent layers of cytoplasm are separated by an interspace that may vary in widths of up to several 100 mu to form intralamellar vesicles.

The Nature of Rapidly Extracted Phycocyanin from the Blue-Green Alga Plectonema Boryanum

1971 ◽  
Vol 29 ◽  
pp. 366-367
Author(s):  
M. Kessel ◽  
R. MacColl
Keyword(s):  
Self Assembly ◽  
Analytical Ultracentrifugation ◽  
Uranyl Acetate ◽  
The Self ◽  
Major Protein ◽  
Subunit Structure ◽  
Blue Green Alga ◽  
Thin Sections ◽  
Blue Green Algae ◽  
Cacodylate Buffer

The major protein of the blue-green algae is the biliprotein, C-phycocyanin (Amax = 620 nm), which is presumed to exist in the cell in the form of distinct aggregates called phycobilisomes. The self-assembly of C-phycocyanin from monomer to hexamer has been extensively studied, but the proposed next step in the assembly of a phycobilisome, the formation of 19s subunits, is completely unknown. We have used electron microscopy and analytical ultracentrifugation in combination with a method for rapid and gentle extraction of phycocyanin to study its subunit structure and assembly.To establish the existence of phycobilisomes, cells of P. boryanum in the log phase of growth, growing at a light intensity of 200 foot candles, were fixed in 2% glutaraldehyde in 0.1M cacodylate buffer, pH 7.0, for 3 hours at 4°C. The cells were post-fixed in 1% OsO4 in the same buffer overnight. Material was stained for 1 hour in uranyl acetate (1%), dehydrated and embedded in araldite and examined in thin sections.

New constituents from Oryza sativa L. straw and their algicidal activities against blue-green algae

2017 ◽  
Vol 40 (1) ◽  
pp. 47-62 ◽  
Author(s):  
I. M. Chung ◽  
S. H. Kim ◽  
Y.T. Oh ◽  
M. Ali ◽  
A. Ahmad
Keyword(s):  
Oryza Sativa ◽  
Green Algae ◽  
Oryza Sativa L ◽  
Blue Green Algae

ISOLATION, IDENTIFICATION AND CHARACTERIZATION OF A STRAIN OF BLUE-GREEN ALGAE-LYSING BACTERIUM FROM LAKE DIANCHI

2009 ◽  
Vol 33 (5) ◽  
pp. 860-865
Author(s):  
Lan-Lan LU ◽  
Gen-Bao LI ◽  
Yin-Wu SHEN ◽  
Ming-Ming HU ◽  
Yong-Ding LIU
Keyword(s):  
Green Algae ◽  
Lake Dianchi ◽  
Blue Green Algae ◽  
Identification And Characterization

The relationship between musty-odor-causing organisms and water quality in Lake Biwa

1995 ◽  
Vol 31 (11) ◽  
pp. 153-158 ◽  
Author(s):  
M. Kajino ◽  
K. Sakamoto
Keyword(s):  
Water Quality ◽  
Data Analysis ◽  
Green Algae ◽  
Analytical Methods ◽  
Lake Biwa ◽  
Blue Green Algae ◽  
Odor Compounds ◽  
Musty Odor ◽  
The Relationship

Musty odor has occurred annually in Lake Biwa since 1969. Osaka municipal waterworks, which is located downstream of Lake Biwa, has made many efforts to treat musty-odor compounds produced in Lake Biwa from spring through autumn. With the development of analytical methods for the determination of musty-odor compounds, we have been able to confirm that planktonic blue-green algae are the major causes of the musty-odor occurrences. The relationship between the growth of blue-green algae and the water quality was not so apparent. However, through our data analysis focusing on the relationship between musty-odor occurrences due to Phormidium tenue or Oscillatoria tenuis and some nutrients in Lake Biwa, we found that the concentration of nitrate in water may be an important parameter for the estimation of growth of the algae and the musty-odor behavior.

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