Results 141 to 150 of about 1,898 (177)

Heterocystous versus non-heterocystous cyanobacteria in microbial mats

1994
Relative to biological demands, marine waters are often depleted in combined forms of nitrogen (Dugdale 1967). As such, the development of microbial mats in coastal marine environments is dependent on the fixation of atmospheric dinitrogen as the dominant source of biologically available N.
Lucas J. Stal, Hans W. Paerl, Brad Bebout, Marlies Villbrandt   +3 more
openaire   +1 more source

On the reversibility of heterocyst differentiation

British Phycological Journal, 1974
Heterocyst development in the blue-green alga Anabaena cylindrica Lemm. was arrested by ammonia at an early stage of differentiation only. No dedifferentiation or germination of heterocysts in the presence of ammonia could be detected.
S.A. Kulasooriya, Peter Fay
openaire   +1 more source

Chemical composition and production of exopolysaccharides from representative members of heterocystous and non-heterocystous cyanobacteria

Phytochemistry, 1999
Exopolysaccharide (EPS) production and chemical composition of heterocystous and non-heterocystous cyanobacteria of subgroups 3, 4, and 5 together with four new species isolated from Pantelleria (Italy) hard sands and from a lake in the proximity of Edmonson Point in Antarctica were studied.
B Nicolaus, A Panico, L Lama, I Romano, M C Manca, A De Giulio, A Gambacorta   +6 more
openaire   +3 more sources

Heterocyst Envelope Glycolipids

2009
Heterocyst-forming cyanobacteria simultaneously photosynthesize, producing oxygen (O2), and fix dini-trogen (N2), initially into ammonia, using nitrogenase enzymes that are rapidly inactivated by O2. These cyanobacteria enable nitrogenases to function in an oxic environment by segregating them within specialized cells, called heterocysts, in which O2 ...
Koichiro Awai, Sigal Lechno-Yossef, C. Peter Wolk   +2 more
openaire   +1 more source

Properties of heterocysts isolated with colloidal silica

Archives of Microbiology, 1976
A method is described for the isolation of heterocysts that are virtually free of contaminating cell debris after sonication of aerobically grown Anabaena 7120. Isolated heterocysts reduced acetylene in a light-dependent process in the absence of exogenously provided ATP; heterocysts supplied with ATP and Na2S2O4 reduced acetylene slowly in the dark ...
R B, Peterson, R H, Burris
openaire   +2 more sources

Heterocyst Differentiation in Anabaena ambigua

Biochemie Und Physiologie Der Pflanzen, 1976
Summary The undifferentiated algal filaments of Anabaena ambigua Rao were exposed to N-methyl-N'-nitro-N-nitrosoguanidine (NTG), and UV-irradiation during the induction period of heterocyst formation. NTG has been observed to inhibit the heterocyst differentiation by affecting the enzyme level.
A K Rai
exaly   +2 more sources

Heterocyst Metabolism and Development

1994
Heterocysts are differentiated cells that are specialized for fixation of N2 in an aerobic environment. In heterocysts in the light, Photosystem I generates ATP, but no photosynthetic production of O2 takes place. Instead, reductant moves into heterocysts from vegetative cells. In return, fixed nitrogen moves from heterocysts to vegetative cells.
C. Peter Wolk, Anneliese Ernst, Jeff Elhai   +2 more
openaire   +1 more source

Excision of the nifD element in the heterocystous cyanobacteria

Archives of Microbiology, 2008
Heterocyst differentiation in cyanobacteria is accompanied by developmentally regulated DNA rearrangements that occur within the nifD, fdxN, and hupL genes. These genetic elements are excised from the genome by site-specific recombination during the latter stages of differentiation.
B J, Henson, L E, Pennington, L E, Watson, S R, Barnum   +3 more
openaire   +2 more sources

Heterocyst structure in Chlorogloea fritschii

Archiv f�r Mikrobiologie, 1967
Heterocysts of Chlorogloea fritschii were studied with the aid of light and electron microscopy. Two main types of heterocyst were recognized. One of these, termed here the H.1 cell, is the only type in filaments, but occurs also among endospore groups. The other, the H.3 cell, is restricted to endospore groups.
B. A. Whitton, A. Peat
openaire   +1 more source

THE HETEROCYSTS OF BLUE‐GREEN ALGAE (MYXOPHYCEAE)

Biological Reviews, 1975
Summary1. Heterocysts are found in many species of filamentous blue‐green algae. They are cells of slightly larger size and with a more thickened wall than the vegetative cells.2. Structural details of the heterocyst are: the presence of three additional wall layers, the absence of granules, sparse thylakoid network throughout, except at the poles ...
openaire   +2 more sources