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A large, thick-walled, nitrogen-fixing cell that occurs at intervals along the filaments of certain cyanobacteria.


(Biology) biology a special cell type found in cyanobacteria and responsible for fixing nitrogen


(ˈhɛt ər əˌsɪst)

one of the enlarged nitrogen-fixing cells along the filaments in some blue-green algae.
References in periodicals archive ?
Several studies depicted that B is involved in increasing the absorption of N through fixation in heterocyst cells.
As free oxygen deactivates the nitrogenase, the cell wall of the heterocyst is made of a thick and densely laminated glycolipid layer with a thin polysaccharide layer on the outer surface to prevent diffusion of oxygen into the cell.
Heterocystscylindric, intercalary, 5-7 [micro]m in diameter and 7-20 [micro]m long, akinetes elongate, cylindric, solitary formed near the middle of the trichome but not adjacent to the heterocyst, 6-8 [micro]m in diameter and 20-60 [micro]m long (Fig.
Cyanobacterial heterocyst glycolipids in cultures and environmental samples: Diversity and biomarker potential.
Cyanobacteria are morphologically diverse and they consist of unicellular, colonial, pseudofilamentous, pseudoparenchymatous uniseriate, filamentous forms unbranched, undifferentiated, differentiated with specialized cells called heterocyst and akinetes and heterotrichous branched forms [2].
Most of the cyanobionts appear to be heterocystous which is as close to a multicellular organisation as is possible in these bacteria in which hexose, produced by photosynthesis, moves from the vegetative cells to the heterocyst (Meeks & Elhai, 2002).
News_ID=735007981 heterocyst order soma online http://www.
In cultures of the two-membered assemblage, 10 to 50 epibiotic cells were attached to each heterocyst (Fig.
However, the heterocystous cyanobacteria have an 11 kb insertion element present within the coding region of nifD, which is excised by site specific recombination during heterocyst differentiation.
if heterocysts are present only when DIN is low, then heterocyst
Richellia forms short filaments, generally with a heterocyst (a differentiated nitrogen-fixing cell) at one end, and they are usually found as internal symbionts within larger diatom cells.