Naturwissenschaften

, 96:1 | Cite as

The riddle of “life,” a biologist’s critical view

Review

Abstract

To approach the question of what life is, we first have to state that life exists exclusively as the “being-alive” of discrete spatio-temporal entities. The simplest “unit” that can legitimately be considered to be alive is an intact prokaryotic cell as a whole. In this review, I discuss critically various aspects of the nature and singularity of living beings from the biologist’s point of view. In spite of the enormous richness of forms and performances in the biotic realm, there is a considerable uniformity in the chemical “machinery of life,” which powers all organisms. Life represents a dynamic state; it is performance of a system of singular kind: “life-as-action” approach. All “life-as-things” hypotheses are wrong from the beginning. Life is conditioned by certain substances but not defined by them. Living systems are endowed with a power to maintain their inherent functional order (organization) permanently against disruptive influences. The term organization inherently involves the aspect of functionality, the teleonomic, purposeful cooperation of structural and functional elements. Structures in turn require information for their specification, and information presupposes a source. This source is constituted in living systems by the nucleic acids. Organisms are unique in having a capacity to use, maintain, and replicate internal information, which yields the basis for their specific organization in its perpetuation. The existence of a genome is a necessary condition for life and one of the absolute differences between living and non-living matter. Organization includes both what makes life possible and what is determined by it. It is not something “implanted” into the living beings but has its origin and capacity for maintenance within the system itself. It is the essence of life. The property of being alive we can consider as an emergent property of cells that corresponds to a certain level of self-maintained complex order or organization.

Keywords

Living state Vital organization Metabolism Self-maintenance Autonomy Emergence 

References

  1. Alberts B, Bray D, Lewis J, Raff M, Roberts K, Watson JD (1995) Molekularbiologie der Zelle. 3. Aufl. VCH Chemie, WeinheimGoogle Scholar
  2. Anderson PW (1972) More is different. Science 177:393–396PubMedGoogle Scholar
  3. Bamford DH, Grimes JM, Stuart DJ (2005) What does structure tell us about virus evolution? Curr Opinion Structural Biol 15:655–663Google Scholar
  4. Bapteste E, Brochier C (2004) On the conceptual difficulties in rooting the tree of life. Trends Micobiol 12:9–13Google Scholar
  5. Bereiter-Hahn J, Airas J, Blum S (1997) Supramolecular associations with the cytomatrix and their relevance in metabolic control: Protein synthesis and glycolysis. Zoology 100:1–24Google Scholar
  6. Bertalanffy L v (1932) Theoretische Biologie. 1. Band: Allgemeine Theorie, Physikochemie, Aufbau und Entwicklung des Organismus. Gebr. Borntraeger, BerlinGoogle Scholar
  7. Blair JE, Hedges SB (2005) Molecular phylogeny and divergence of deuterostome animals. Mol Biol Evol 22:2275–2284PubMedGoogle Scholar
  8. Breitbart M, Rohwer F (2005) Here a virus, there a virus, everywhere the same virus? Trends Microbiol 13:278–284PubMedGoogle Scholar
  9. Brücke E (1851) Die Elementarorganismen. Sitzungsber Kgl Akad Wissensch in Wien, Mathem.-Naturwiss. Klasse 44:381–466Google Scholar
  10. Butterfield NJ, Knoll AH, Swett K (1990) A bangiophyte red alga from the proterozoic of arctic Canada. Science 250:104–107PubMedGoogle Scholar
  11. Campbell DT (1974) Downward causation in hierarchically organized biological systems. In: Ayala F, Dobzhansky T (eds) Studies in the philosophy of biology. University of California Press, Berkeley, pp 179–186Google Scholar
  12. Capra F (1988) Wendezeit. Bausteine für ein neues Weltbild. Droemersche Verlagsanstalt Knaur Nachf., MünchenGoogle Scholar
  13. Cramer F (1993) Chaos and order. The complex structure of living systems. VCH, WeinheimGoogle Scholar
  14. Crick F (1966) Of molecules and man. Univ. of Washington Press, SeattleGoogle Scholar
  15. Crick F (1968) The origin of the genetic code. J Mol Biol 38:367–379PubMedGoogle Scholar
  16. Deckert G et al (1998) The complete genome of the hyperthermophilic bacterium Aquifex aeolicus. Nature 392:353–358PubMedGoogle Scholar
  17. Dombrowski HJ (1963) Bacteria from palaeozoic salt deposits. Ann NY Acad Sci 108:453–460PubMedGoogle Scholar
  18. Doolittle WF (1999) Phylogenetic classification and the universal tree. Science 284:2124–2128PubMedGoogle Scholar
  19. Eigen M (1987) Stufen zum Leben. Die frühe Evolution im Visier der Molekularbiologie. Piper Verlag, MünchenGoogle Scholar
  20. Embley TM, Martin W (2006) Eukaryotic evolution, changes and challenges. Nature 440:623–630PubMedGoogle Scholar
  21. Feynman RP, Leighton RB, Sands M (1989) Lectures of physics, vol.1. California Institute Technology, Pasadena, CAGoogle Scholar
  22. Fong P (1968) Phenomenology theory of life. J Theor Biol 21:133–152PubMedGoogle Scholar
  23. Forterre P, Philippe H (1999) Where is the root of the universal tree of life? Bioessays 21:871–879PubMedGoogle Scholar
  24. Freeland SJ, Hurst LD (1998) The genetic code is one in million. J Mol Evol 47:238–248PubMedGoogle Scholar
  25. Freeland SJ, Wu T, Keulmann N (2003) The case for an error minimising standard genetic code. Orig life 33:457–477Google Scholar
  26. Gil R, Silva FJ, Peretó J, Moya A (2004) Determination of the core of a minimal bacteria gene set. Microbiol Mol Biol Rev 68:518–537PubMedGoogle Scholar
  27. Glansdorff P, Prigogine I (1971) Thermodynamic theory of structure, stability and fluctuations. Wiley, New YorkGoogle Scholar
  28. Glass JI et al (2006) Essential genes of a minimal bacterium. Proc Natl Acad Sci USA 103:425–430PubMedGoogle Scholar
  29. Gogarten JP (1995) The early evolution of cellular life. Trends Ecol Evol 10:147–151Google Scholar
  30. Gogarten JP, Taiz L (1992) Evolution of proton pumping ATPases: rooting the tree of life. Photosynth Res 33:137–146Google Scholar
  31. Gogarten JP, Doolittle WF, Lawrence JG (2002) Prokaryotic evolution in light of gene transfer. Mol Biol Evol 19:2226–2238PubMedGoogle Scholar
  32. Haldane JS (1922) Respiration. New Haven, London, OxfordGoogle Scholar
  33. Haldane JBS (1929) The origin of life. The Rationalist Annual 148:3–10, (reprinted in: Bernal JD, 1967)Google Scholar
  34. Hall TS (1969) History of general physiology, 2 vols. Univ. Chicago Press, ChicagoGoogle Scholar
  35. Hayes JM (1996) The earliest memories of life on earth. Nature 384:21–22PubMedGoogle Scholar
  36. Heidenhain M (1894) Neue Untersuchungen über die Centralkörper und ihre Beziehungen zum Kern und Zellenprotoplasma. Arch Mikroskop Anat 43:423–758Google Scholar
  37. Hertwig O (1906) Allgemeine Biologie. Fischer Verlag, JenaGoogle Scholar
  38. Hess B, Boitew A (1971) Oscillatory phenomena in biochemistry. Ann Rev Biochem 40:237–258PubMedGoogle Scholar
  39. Hess B, Goldbeter A, Lefever R (1978) Temporal, spatial, and functional order in regulated biochemical and cellular systems. In: Rice SA (ed) Advances in chemical physics 38. Wiley, New York, pp 363–413Google Scholar
  40. Hou L, Luby-Phelps K, Lanni F (1990) Brownian motion of inert tracer macromolecules in polymerized and spontaneously bundled mixtures of actin and filamin. J Cell Biol 110:1645–1654PubMedGoogle Scholar
  41. Hull DL (1974) Philosophy of biological science. Prentice Hall, Englewood Cliffs, NJGoogle Scholar
  42. Hulswit M (2006) How causal is downward causation? J Gen Philosophy of Science 36:261–287Google Scholar
  43. Islas S, Becerra A, Luisi PL, Lazcano A (2004) Comparative genomics and the gene complement of a minimal cell. Orig Life Evol Bioph 34:243–256Google Scholar
  44. Jacob F (1982) The possible and the actual. Pantheon, New YorkGoogle Scholar
  45. Jacob F (1993) The logic of life. A history of heredity. Princeton University Press, Princeton, NJGoogle Scholar
  46. Jantsch E (1984) Die Selbstorganisation des Universums. Vom Urknall zum menschlichen Geist. 2. Aufl., Deutscher Taschenbuch Verlag, MünchenGoogle Scholar
  47. Joyce GF (1987) Cold Spring Harbor Symp Quant Biol 52Google Scholar
  48. Joyce GF, Orgel LE (1986) J Mol Biol 188:433–437PubMedGoogle Scholar
  49. Joyce GF, Orgel LE (1993) Prospects for understanding the origin of the RNA world. In: Gesteland RF, Atkins JF (eds) The RNA world. Cold Spring Habor Laboratory Press, New York, pp 1–25Google Scholar
  50. Kacser H, Burns JA (1979) Molecular democracy: who shares the controls? Biochem Soc Trans 7:1149–1160PubMedGoogle Scholar
  51. Kant I (1790) Kritik der Urtheilskraft. Lagarde und Friederich, Berlin und Libau (quoted from: Cambridge Edition of the Works of Immanuel Kant, edited by Paul Guyer and Allen W. Wood. Cambridge Univ. Press, Cambridge 1992)Google Scholar
  52. Kaplan RW (1972) Der Ursprung des Lebens. Biogenetik, ein Forschungsgebiet heutiger Naturwissenschaft. Georg Thieme, StuttgartGoogle Scholar
  53. Kaufmann SA (1993) The origin of order: Self-organization and selection in evolution. Oxford University Press, New YorkGoogle Scholar
  54. Kaufmann S (1996) Even peptides do it. Nature 382:496–497Google Scholar
  55. Kay LE (2000) Who wrote the book of life? Stanford Univ. Press, Stanford, CAGoogle Scholar
  56. Kelso JAS, Haken H (1997) Im Organismus sind neue Gesetze zu erwarten. Synergetik von Gehirn und Verhalten. In: Murphy MP, O’Neill LAJ (eds) Was ist Leben? Die Zukunft der Biologie. Spektrum Akademischer Verlag, Heidelberg, pp 157–182Google Scholar
  57. Kennedy MJ, Reader SL, Swierczynski LM (1994) Preservation records of microorganisms: Evidence of the tenacity of life. Microbiol 140:2513–2529CrossRefGoogle Scholar
  58. Koonin EV, Martin W (2005) On the origin of genomes and cells within inorganic compartments. Trends Genet 21:647–654PubMedGoogle Scholar
  59. Koonin EV, Senkevich TG, Dolja VV (2006) The ancient virus world and evolution of cells. Biology Direct 2006:1–27Google Scholar
  60. Koshland DE (1987) Switches, thresholds and ultrasensitivity. Trends Biochem Sci 12:225–229Google Scholar
  61. Kratky KW (1990) Der Paradigmenwechsel von der Fremd- zur Selbstorganisation. In: Kratky KW, Wallner F (eds) Grundprinzipien der Selbstorganisation. Wissensch. Buchgesellschaft, Darmstadt, pp 3–17Google Scholar
  62. Kuhn TS (1962) The structure of scientific revolutions. Univ. of Chicago Press, Chicago, ILGoogle Scholar
  63. Kuhn H, Waser J (1982) Selbstorganisation der Materie und Evolution früher Formen des Lebens. In: Hoppe W, Lohmann W, Markl H, Ziegler H (eds) Biophysik, 2. Aufl. Springer, Berlin, pp 860–905Google Scholar
  64. Kutschera U (2006) Constantin S. Merezhkowsky (1855–1921) und die Endosymbiontentheorie der Zellevolution. Biologen heute 1:11–15Google Scholar
  65. Kutschera U, Niklas KJ (2005) Endosymbiosis, cell evolution, and speciation. Theory Biosci 124:1–24PubMedGoogle Scholar
  66. Laczano A (1993) In: Bengston S (ed) Early life on earth. Nobel Symposium No. 84, Columbio University Press, pp 59–80Google Scholar
  67. Lamarck J de (1815) Histoire naturelle des animaux sans vertebras, vol. 1, ParisGoogle Scholar
  68. Langton CG (1995) Editor’s introduction. In: Artificial life. An overview. MIT Press, Cambridge, MAGoogle Scholar
  69. Larralde R, Robertson MP, Miller SL (1995) Rates of decomposition of ribose and other sugars: Implications for chemical evolution. Proc Natl Acad Sci USA 92:8158–8160PubMedGoogle Scholar
  70. Lewes GW (1879) Problems of life and mind. Trubner, LondonGoogle Scholar
  71. Lowentin RC (1992) The dream of the human genome. The New York Review, pp 31–40Google Scholar
  72. Luisi PL (1999) Lipid vesicles as possible intermediates in the origin of life. Curr Opin Colloid Interface Sci 4:33–39Google Scholar
  73. Luisi PL, Ferri F, Stano P (2006) Approaches to semi-synthetic minimal cells: a review. Naturwissenschaften 93:1–13PubMedGoogle Scholar
  74. MacLeod RB (1957) Teleology and theory of human behavior. Science 125:477PubMedGoogle Scholar
  75. Mahner M, Bunge M (1997) Foundation of biophilosophy. Springer, HeidelbergGoogle Scholar
  76. Maier U-G, Hofmann CJB, Sitte P (1996) Die Evolution von Zellen. Naturwissenschaften 83:103–112PubMedGoogle Scholar
  77. Mayr E (1979) Evolution und die Vielfalt des Lebens. Springer, BerlinGoogle Scholar
  78. Mill JS (1843) A system of logic. Longmans, Green and Co., London 1859Google Scholar
  79. Miller SL (1953) A production of amino acids under possible primitive earth conditions. Science 117:528–529PubMedGoogle Scholar
  80. Mills DR, Petersen RL, Spiegelman S (1967) An extracellular Darwinian experiment with a self-duplicating nucleic acid molecule. Proc Nat Acad Sci USA 58:217PubMedGoogle Scholar
  81. Monod J (1972) Chance and necessity. An Essay on the natural philosophy of modern biology. Vintage books, New YorkGoogle Scholar
  82. Moreno A, Umerez J (2000) Downward causation at the core of living organization. In: Andersen PB, Emmeche C, Finnemann NO, Christiansen PV (eds) Downward causation: minds, bodies and matter. Aarhus Univ Press, Aarhus, pp 99–117Google Scholar
  83. Morowitz HJ (1967) Biological self-replicating systems. Prog Theor Biol 1:35–58Google Scholar
  84. Nicholls DG, Ferguson SJ (1992) Bioenergetics. Academic, LondonGoogle Scholar
  85. Oparin AJ (1924) The origin of life (Russian). Moscow (translated in: Bernal JD (1967) The origin of life. London. Deutsch: Die Entstehung des Lebens auf der Erde. 3. Aufl. Dtsch Verlag der Wissenschaften, Berlin 1957Google Scholar
  86. Oparin AI (1961) Life: its nature, origin and development. Academic, New YorkGoogle Scholar
  87. Ostwald W (1926) Zur biologischen Grundlegung der Inneren Medizin. Medizinisch-Biologische Schriftenreihe, Heft 1, Radebeul, pp 5–27Google Scholar
  88. Penzlin H (1987) Das Teleologie-Problem in der Biologie. Biol Rundschau 25:7–26Google Scholar
  89. Penzlin H (1988) Ordnung- Organisation - Organismus. Zum Verhältnis zwischen Physik und Biologie. Sitzungsber. der Sächsischen Akad. d. Wissenschaften zu Leipzig. Math.-Naturwiss. Klasse Bd. 120, Heft 6. Akademie Verlag, BerlinGoogle Scholar
  90. Penzlin H (1993a) Was ist Theoretische Biologie? Biol Zbl 112:100–107Google Scholar
  91. Penzlin H (1993b) Selbstorganisation—Paradigma oder Metapher biologischer Strukturbildung? In: Becker V, Schipperges H (eds) Entropie und Pathogenese. Interdisziplinäres Kolloquium der Heidelberger Akademie der Wissenschaften. Springer, Heidelberg, pp 48–64Google Scholar
  92. Penzlin H (2002) Warum das Autopoiese-Konzept Maturanas die Organisation lebendiger Systeme unzutreffend beschreibt. Philos Nat 39:61–87Google Scholar
  93. Pflüger E (1875) Beiträge zur Lehre von der Respiration (1): Über die physiologische Verbrennung in den lebendigen Organismen. Pflüger’s Archiv 10:251–269, 641–644Google Scholar
  94. Pittendrigh CS (1958) Adaptation, natural selection, and behavior. In: Roe A, Simpson GG (eds) Behavior and evolution. Yale Univ. Press, New Haven, pp 390–416Google Scholar
  95. Pittendrigh CS (1993) Temporal organization: Reflection of a Darwinian clock-watcher. Ann Rev Physiol 55:17–54Google Scholar
  96. Polanyi M (1968) Life’s irreducible structure. Science 160:1308–1312PubMedGoogle Scholar
  97. Prigogine I (1947) Etude thermodynamique des Phenomenes Irreversibles. Desoer, LiegeGoogle Scholar
  98. Riedl R (1981) Biologie der Erkenntnis. Die stammesgeschichtlichen Grundlagen der Vernunft. 3. Aufl. Paul Parey, Berlin, HamburgGoogle Scholar
  99. Rosen R (ed) (1985) Theoretical biology and complexity. Three assays on the natural philosophy of complex systems. Academic Press Inc. Orlando, LondonGoogle Scholar
  100. Rosen R (1991) Life itself: a comprehensive inquiry into the nature, origin and fabrication of life. Columbia University Press, New YorkGoogle Scholar
  101. Roux W (1895) Der züchtende Kampf der Theile oder die “Theilauslese” im Organismus. V. Cap. Ueber das Wesen des Organischen. Gesammelte Abhandlungen über Entwicklungsmechanik der Organismen. 1. Band. Wilhelm Engelmann, Leipzig, pp 387–416Google Scholar
  102. Rual JF et al (2005) Towards a proteome scale map of the human protein-protein interaction network. Nature 437:1173–1178PubMedGoogle Scholar
  103. Russell ES (1945) The directiveness of organic activities. Cambridge University Press, CambridgeGoogle Scholar
  104. Sabater B (2006) Are organisms committed to lower their rates of entropy production? Biosystems 83:10–17PubMedGoogle Scholar
  105. Schrödinger E (1944) What is life? Cambridge University Press, CambridgeGoogle Scholar
  106. Schwartz RM, Daydoff MO (1978) Origins of prokaryotes, eukaryotes, mitochondria, and chloroplasts. Science 199:395–403PubMedGoogle Scholar
  107. Shimkets LJ (1998) Structure and sizes of genomes of the Archaea and Bacteria. In: Bruijn FJ de, Lupskin JR, Weinstock GM (eds) Bacterial genomes: physical structure and analysis. Kluwer, Boston, MA, pp 5–11Google Scholar
  108. Simpson GG (1963) Biology and the nature of science. Science 139:81–88PubMedGoogle Scholar
  109. Srere DA (1993) Wandering (wonderings) in metabolism. Biol Chem 374:833–842Google Scholar
  110. Stelzl U et al (2005) A human protein–protein interaction network: a source for annotating the proteome. Cell 122:957–968PubMedGoogle Scholar
  111. Storch V, Welsch U (2005) Kurzes Lehrbuch der Zoologie. 8. Aufl. Elsevier GmbH, MünchenGoogle Scholar
  112. Thorpe WH (1978) Purpose in the world of chance. Oxford University Press, OxfordGoogle Scholar
  113. Uexküll JV (1928) Theoretische Biologie. 2. Aufl. Springer, BerlinGoogle Scholar
  114. Van Gulick R (1993) Who is in change here? And who’s doing all the work? In: Heil J, Mele A (eds) Mental causation. Oxford Univ Press, Oxford, pp 233–256Google Scholar
  115. Verworn M (1903) Die Biogenhypothese. Fischer Verlag, JenaGoogle Scholar
  116. Vreeland RH, Rosenzweig WD, Powers DW (2000) Isolation of a 250 million-years-old halotolerant bacterium from a primary salt crystal. Nature 407:897–900PubMedGoogle Scholar
  117. Wächterhäuser G (1988) Before enzyme and templates: theory of surface metabolism. Microbiol Rev 52:452–484Google Scholar
  118. Weismann A (1892) Das Keimplasma—eine Theorie der Vererbung. Gustav Fischer, JenaGoogle Scholar
  119. Wicken JS (1987) Evolution, thermodynamics, and information. Oxford Univ. Press, New YorkGoogle Scholar
  120. Woese CR (2000) Interpreting the universal phylogenetic tree. Proc Natl Acad Sci USA 97:8392–8396PubMedGoogle Scholar
  121. Zhaxybayeva O, Lapierre P, Gogarten JP (2005) Ancient gene duplications and the root(s) of the tree of life. Protoplasma 227:53–64PubMedGoogle Scholar

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© Springer-Verlag 2008

Authors and Affiliations

  1. 1.Institut für Allgemeine Zoologie und Tierphysiologie Friedrich-Schiller-Universität JenaJenaGermany
  2. 2.JenaGermany

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