Hostname: page-component-78c5997874-j824f Total loading time: 0 Render date: 2024-11-05T16:22:29.575Z Has data issue: false hasContentIssue false

The fate of proteins in outer space

Published online by Cambridge University Press:  09 December 2015

Gavin M. Seddon
Affiliation:
Adelard Institute, Manchester M29 7FZ, UK
Robert Paul Bywater*
Affiliation:
Adelard Institute, Manchester M29 7FZ, UK Magdalen College, Oxford OX1 4AU, UK

Abstract

It is well established that any properly conducted biophysical studies of proteins must take appropriate account of solvent. For water-soluble proteins it has been an article of faith that water is largely responsible for stabilizing the fold, a notion that has recently come under increasing scrutiny. Further, there are some instances when proteins are studied experimentally in the absence of solvent, as in matrix-assisted laser desorption/ionization or electrospray mass spectrometry, for example, or in organic solvents for protein engineering purposes. Apart from these considerations, there is considerable speculation as to whether there is life on planets other than Earth, where conditions including the presence of water (both in liquid or vapour form and indeed ice), temperature and pressure may be vastly different from those prevailing on Earth. Mars, for example, has only 0.6% of Earth's mean atmospheric pressure which presents profound problems to protein structures, as this paper and a large corpus of experimental work demonstrate. Similar objections will most likely apply in the case of most exoplanets and other bodies such as comets whose chemistry and climate are still largely unknown.

This poses the question, how do proteins survive in these different environments? In order to cast some light on these issues we have conducted a series of molecular dynamics simulations on protein dehydration under a variety of conditions. We find that, while proteins undergoing dehydration can retain their integrity for a short duration they ultimately become disordered, and we further show that the disordering can be retarded if superficial water is kept in place on the surface. These findings are compared with other published results on protein solvation in an astrobiological and astrochemical setting. Inter alia, our results suggest that there are limits as to what to expect in terms of the existence of possible extraterrestrial forms as well to what can be achieved in experimental investigations on living systems despatched from Earth. This finding may appear to undermine currently held hopes that life will be found on nearby planets, but it is important to be aware that the presence of ice and water are by themselves not sufficient; there has to be an atmosphere which includes water vapour at a sufficiently high partial pressure for proteins to be active. A possible scenario in which there has been a history of adequate water vapour pressure which allowed organisms to prepare for a future desiccated state by forming suitable protective capsules cannot of course be ruled out.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2015 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Arteca, G. & Tapia, O. (2002). J. Phys. Chem. B 106, 10811089.Google Scholar
Arteca, G. & Tapia, O. (2003). Mol. Phys. 101, 27432753.Google Scholar
Ball, P. (2013). The importance of water. In Astrochemistry and Astrobiology, ed. Smith, I.W.M., Cockell, C.S., Leach, S., pp. 169–210. Springer, Heidelberg, New York, Dordrecht, London.Google Scholar
Barrera, N.P., Di Bartolo, N., Booth, P.J. & Robinson, C.V. (2008). Science 321, 243246.CrossRefGoogle Scholar
Benesch, J.L.P. & Robinson, C.V. (2009). Nature 462, 576577.CrossRefGoogle Scholar
Ben-Naim, A. (2012). J. Biomol. Struct. Dyn. 30, 113124.Google Scholar
Breuker, K. & McLafferty, F.W. (2008). Proc. Natl. Acad. Sci. USA 105, 1814518152.Google Scholar
Bywater, R.P. (2013). J. Biomol. Struct. Dyn. 31, 967969.Google Scholar
Case, D.A. et al. (2010). AMBER 11. University of California, San Francisco.Google Scholar
Chen, X.F., Weber, I. & Harrison, R.W. (2008). J. Phys. Chem. B 112, 1207312080.CrossRefGoogle Scholar
Goesmann, F. et al. (2015). Science 349(6247), DOI:10.1126/science.aab0689.CrossRefGoogle ScholarPubMed
Gurnett, D.A. (2009). Trans. Am. Clin. Climatol. Assoc. 120, 299325.Google Scholar
Herschel, W. (1784). Phil. Trans. R. Soc. 1784, 233.Google Scholar
Jarrold, M.F. (2007). Phys. Chem. Chem. Phys. 9, 16591671.CrossRefGoogle Scholar
Jorgensen, W.L. & Madura, J.D. (1985). Mol. Phys. 56, 13811392.Google Scholar
Kauzmann, W. (1959). Adv. Prot. Chem. 14, 163.Google Scholar
Klibanov, A.M. (2010). Nature 409, 241246.Google Scholar
Krieger, E., Koraimann, G. & Vriend, G. (2002). Proteins 47, 393402.Google Scholar
Levitt, M., Hirschberg, R., Sharon, K.E., Daggett, V. (1997). J. Phys. Chem. B 101, 50515056.CrossRefGoogle Scholar
Liu, Z. & Schey, K.L. (2008). J. Am. Soc. Mass. Spectrom. 19, 231238.CrossRefGoogle Scholar
Liu, L., Bagal, D., Kitova, E.N., Schnier, P.D. & Klassen, J.S. (2009). J. Am. Chem. Soc. 131, 1598015981.Google Scholar
Meyer, T., de la Cruz, X. & Orozco, M. (2009). Structure 17, 8895.Google Scholar
Nutt, D.R. & Smith, J.C. (2007). J. Chem. Theory Comput. 3, 15501560.Google Scholar
Patriksson, A., Marklund, E., Van der Spoel, D. (2007). Biochemistry 46, 933945.Google Scholar
Risso, V.A., Gavira, J.A., Gaucher, E.A. & Sanchez-Ruiz, J.M. (2014). Proteins 82, 887896.Google Scholar
Robinson, C.V., Sali, A. & Baumeister, W. (2007). Nature 450, 973982.Google Scholar
Rummel, J.D. et al. (2014). Astrobiology 14, 887968.Google Scholar
Seibert, M.M., Patriksson, A., Hess, B. & Van der Spoel, D. (2005). J. Mol. Biol. 354, 173183.Google Scholar
Smith, R.D., Loo, J.A., Edmonds, C.G., Barinaga, C.J. & Udseth, H.R. (1990). Anal. Chem. 62, 882899.Google Scholar
Soares, C.M., Teixeira, V.H. & Baptista, A.M. (2003). Biophys. J. 84, 16281641.CrossRefGoogle Scholar
Van Aalten, D.M.F., Amadei, A., Bywater, R.P., Findlay, J.B.C., Berendsen, H.J.C., Sander, C. & Stouten, P.F.W. (1996). Biophys. J. 70, 684692.Google Scholar
Vriend, G. (1990). J. Mol. Graph. 8, 5256.Google Scholar
Wallace, A.R. (1907). Is Mars Habitable? A critical examination of Professor Lowell's book ‘Mars and Its Canals’ with an alternative explanation. Available for download from http://people.wku.edu/charles.smith/wallace/S730.htm Google Scholar
Wedberg, R., Abildskov, J. & Peters, G.H. (2012). J. Phys. Chem. B 116, 25752585.Google Scholar
Wyttenbach, T. & Bowers, M.T. (2007). Ann. Rev. Phys. Chem. 58, 511533.Google Scholar