Physical properties of blue-green algae: Ultracentrifugation and electron microscope studies

PROTOPLASMA ◽  
1977 ◽  
Vol 92 (3-4) ◽  
pp. 229-242 ◽  
Author(s):  
H. W. Beams ◽  
R. G. Kessel
Keyword(s):  
Electron Microscope ◽  
Physical Properties ◽  
Green Algae ◽  
Blue Green Algae

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.

A study of several blue-green algae in the electron microscope

1962 ◽  
Vol 44 (3) ◽  
pp. 311-322 ◽  
Author(s):  
J. A. Chapman ◽  
M. R. J. Salton
Keyword(s):  
Electron Microscope ◽  
Green Algae ◽  
Blue Green Algae

Improved staining of extracellular polymer surrounding Eucapsis sp. and Anabena cylindrica: a comparative study

1974 ◽  
Vol 20 (5) ◽  
pp. 735-738
Author(s):  
Gerald D. Cagle
Keyword(s):  
Electron Microscope ◽  
Comparative Study ◽  
Green Algae ◽  
Freeze Drying ◽  
Ruthenium Red ◽  
Blue Green Algae ◽  
Modified Method ◽  
Ruthenium Red Staining ◽  
Extracellular Polymer

Extracellular polymer surrounding two blue-green algae, Eucapsis sp. (No. 1519) and Anabena cylindrica Lemm. (No. 629), was examined with the electron microscope. Conventional glutaraldehyde–OsO4 fixation, freeze-drying before fixation, and two ruthenium red staining procedures (Luft's method and the modified method of Cagle et al.) were used. The data obtained indicate that observation of extracellular polymer is successively enhanced over conventional fixation when (i) freeze-drying, (ii) Luft's ruthenium red method, and (iii) the modified method of Cagle et al. are used. Each of the methods was also observed to improve cytological detail, particularly in A. cylindrica.

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-DRYING OF BLUE-GREEN ALGAE FOR ELECTRON MICROSCOPE STUDIES1

1967 ◽  
Vol 3 (4) ◽  
pp. 161-165 ◽  
Author(s):  
Tom D. Rogers ◽  
Vernon E. Scholes ◽  
Harold E. Schlichting
Keyword(s):  
Electron Microscope ◽  
Green Algae ◽  
Freeze Drying ◽  
Blue Green Algae

The heterocysts of blue-green algae I. Ultrastructural integrity after isolation

1971 ◽  
Vol 178 (1051) ◽  
pp. 185-192 ◽  
Keyword(s):  
Cell Wall ◽  
Electron Microscope ◽  
Internal Structure ◽  
Green Algae ◽  
Osmotic Shock ◽  
Anabaena Cylindrica ◽  
Vegetative Cells ◽  
Blue Green Algae ◽  
Mechanical Disruption ◽  
Physiological Properties

The heterocysts of Anabaena cylindrica were freed from filaments by differential disruption of vegetative cells using four techniques: mechanical disruption by French press, sonication, osmotic shock and lysozyme. The ultrastructure of isolated heterocysts was compared with that of heterocysts in intact filaments. The first three methods produced heterocysts whose internal structure showed different degrees of damage, involving in particular disruption of the heterocyst cell wall and plasmalemma. Isolation by the lysozyme method yielded heterocysts which appeared in the electron microscope to be intact and comparable with those of the untreated controls. These results suggest that earlier reports on the physiological properties of heterocysts isolated by means of the French press or sonication may require re-examination.

Sign in / Sign up

Export Citation Format

Share Document