In Search of the Molecules of Life

✍ Scribed by Ronald L. Crawford; Andrzej Paszczynski; Qingyong Lang; I.Francis Cheng; Bruce Barnes; Tony J. Anderson; Richard Wells; Chien Wai; Giancarlo Corti; Lisa Allenbach; Daniel P. Erwin; Joohye Park; Touraj Assefi; Mohammad Mojarradi

• Book ID: 102570782
• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 182 KB
• Volume: 154
• Category: Article
• ISSN: 0019-1035
• DOI: 10.1006/icar.2001.6714

✦ Synopsis

The remote detection of a chemical signature of extraterrestrial life ideally requires a broad and nonEarth-centric definition of life. Thus, our proposed approach to detection is based on fundamental thermodynamic assumptions, and some assumptions of how life might obtain energy from its environment. Life, defined as the ability to self-perpetuate, requires a continual input of energy and information. The energy must be tapped in controlled oxidationreduction reactions between electron donors and acceptors along an electron transport chain. Therefore, the core chemical components of such electron transport chains should be detectable as a signature of life. On Earth, such core structures are principally molecules resembling the porphyrins, quinones, flavins, and nicotinamides (e.g., photosynthetic or respiratory pigments, redox enzymes, and cytochromes). Similar redox-active molecules, perhaps with different structures, might be associated with extraterrestrial life. To validate an approach based on redox signature, signature chemicals were extracted from soil and analyzed by different methods and