In this section
@article{Olsson-Francis:2013:10.1017/s1473550413000104,
author = {Olsson-Francis, K and Watson, JS and Cockell, CS},
doi = {10.1017/s1473550413000104},
journal = {International Journal of Astrobiology},
pages = {292--303},
title = {Cyanobacteria isolated from the high-intertidal zone: a model for studying the physiological prerequisites for survival in low Earth orbit},
url = {http://dx.doi.org/10.1017/s1473550413000104},
volume = {12},
year = {2013}
}
TY - JOUR
AB - <jats:title>Abstract</jats:title><jats:p>Cyanobacteria are capable of surviving the adverse conditions of low Earth orbit (LEO). We have previously demonstrated that<jats:italic>Gloeocapsa</jats:italic>strain OU_20,<jats:italic>Chroococcidiopsis</jats:italic>and akinetes of<jats:italic>Anabaena cylindrica</jats:italic>were able to survive 548 days of exposure to LEO. Motivated by an interest to understand how cyanobacteria can survive in LEO, we studied the strategies that<jats:italic>Gloeocapsa</jats:italic>strain OU_20 employs to survive in its natural environment, the upper region of the intertidal zone. Here, cyanobacteria are exposed to fluctuations in temperature, UV radiation, desiccation and salinity. We demonstrated that an increase in salinity from 6.5‰ (BG-11 medium) to 35.7‰ (similar to that of seawater), resulted in increased resistance to UV radiation (254 nm), vacuum (0.7×10<jats:sup>−3</jats:sup>±0.01 kPa) and cold temperatures (–20 °C). Concomitantly, biochemical analyses demonstrated that the amount of fatty acids and mycosporine-like amino acids (a UV absorbing pigment) were higher in the stressed cells. Morphological analysis demonstrated that the electron density and thickness of the mucilaginous sheath were also greater than in the control cells. Yet, the control and stressed cells both formed aggregates. As a result of studying the physiological adaptation of<jats:italic>Gloeocapsa</jats:italic>strain OU_20 in response to salinity, we postulate that survival in the high-intertidal zone and LEO involves a dense extracellular mucilaginous sheath and the formation of aggregates. We conclude that studying the physiological adaptation of cyanobacteria in the intertidal zone provides insight into understanding survival in LEO.</jats:p>
AU - Olsson-Francis,K
AU - Watson,JS
AU - Cockell,CS
DO - 10.1017/s1473550413000104
EP - 303
PY - 2013///
SN - 1473-5504
SP - 292
TI - Cyanobacteria isolated from the high-intertidal zone: a model for studying the physiological prerequisites for survival in low Earth orbit
T2 - International Journal of Astrobiology
UR - http://dx.doi.org/10.1017/s1473550413000104
VL - 12
ER -