Pressure tolerance of brine shrimp (Artemia)

ABSTRACT

Life adapts to various environments, including high temperatures and high pressures. The brine shrimp Artemia was used to investigate the tolerance to hydrostatic pressure up to 750 bar. The swimming activity of Artemia nauplii (larval form) decreased as pressure increased, and the activity became null at 400 bar and above. Interestingly, at 300 bar and less, the swimming activity gradually recovered even under pressure within a short period of time. Up to 500 bar, the activity was reversibly recovered by reducing the pressure to 1 bar. These results could be explained by reversible responses of protein functions and membrane structures, as well as temporal adaptation of cell functions to pressure. The upper limit pressure at which the swimming activity was reversible or irreversible matched that for macromolecular synthesis (500 bar). Altogether, these results indicate that eukaryotes and prokaryotes can temporarily adapt to a high pressure of 500 bar and less.

KEYWORDS:

• Artemia
• high pressure tolerance
• adaptation

Acknowledgments

We thank Prof. Chieko Koike of Ritsumeikan University and Prof. Fumiyoshi Abe of Aoyama Gakuin University for providing valuable feedback on an early version of the manuscript. We also thank Dr. Jin Nakatani (Ritsumeikan University) for assisting sample preparation and Profs. Yoshihiro Taniguchi and Minoru Kato (Ritsumeikan University) for providing high-pressure appratuses.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

All data generated or analyzed during this study are included in this published article.

Additional information

Notes on contributors

Ryo Kitahara

R.K. designed the research. H.U. and K.E. performed the experiments. R.K., H.U., U.T., and K.E. analyzed the data. R.K. drafted and all authors reviewed the manuscript.