An akinete is an enveloped, thick-walled, non-motile, dormant cell formed by filamentous, heterocyst-forming cyanobacteria under the order Nostocales and Stigonematales. [1] [2] [3] [4] Akinetes are resistant to cold and desiccation. [1] They also accumulate and store various essential material, both of which allows the akinete to serve as a survival structure for up to many years. [1] [4] However, akinetes are not resistant to heat. [1] Akinetes usually develop in strings with each cell differentiating after another and this occurs next to heterocysts if they are present. [1] Development usually occurs during stationary phase and is triggered by unfavorable conditions such as insufficient light or nutrients, temperature, and saline levels in the environment. [1] [4] Once conditions become more favorable for growth, the akinete can then germinate back into a vegetative cell. [5] Increased light intensity, nutrients availability, oxygen availability, and changes in salinity are important triggers for germination. [5] In comparison to vegetative cells, akinetes are generally larger. [4] [6] This is associated with the accumulation of nucleic acids which is important for both dormancy and germination of the akinete. [6] Despite being a resting cell, it is still capable of some metabolic activities such as photosynthesis, protein synthesis, and carbon fixation, albeit at significantly lower levels. [3]
Akinetes can remain dormant for extended periods of time. Studies have shown that some species could be cultured that were 18 and 64 years old. [7]
Akinete formation also influences the perennial blooms of cyanobacteria. [8]
An akinete is an enveloped, thick-walled, non-motile, dormant cell formed by filamentous, heterocyst-forming cyanobacteria under the order Nostocales and Stigonematales. [1] [2] [3] [4] Akinetes are resistant to cold and desiccation. [1] They also accumulate and store various essential material, both of which allows the akinete to serve as a survival structure for up to many years. [1] [4] However, akinetes are not resistant to heat. [1] Akinetes usually develop in strings with each cell differentiating after another and this occurs next to heterocysts if they are present. [1] Development usually occurs during stationary phase and is triggered by unfavorable conditions such as insufficient light or nutrients, temperature, and saline levels in the environment. [1] [4] Once conditions become more favorable for growth, the akinete can then germinate back into a vegetative cell. [5] Increased light intensity, nutrients availability, oxygen availability, and changes in salinity are important triggers for germination. [5] In comparison to vegetative cells, akinetes are generally larger. [4] [6] This is associated with the accumulation of nucleic acids which is important for both dormancy and germination of the akinete. [6] Despite being a resting cell, it is still capable of some metabolic activities such as photosynthesis, protein synthesis, and carbon fixation, albeit at significantly lower levels. [3]
Akinetes can remain dormant for extended periods of time. Studies have shown that some species could be cultured that were 18 and 64 years old. [7]
Akinete formation also influences the perennial blooms of cyanobacteria. [8]