Interstellar biomolecules and infrared astronomy

Abstract

The ubiquitous presence of organic molecules in the interstellar clouds, comets and asteroids, and the evidence of extraterrestrial amino acids in carbonaceous meteorites strongly support a cosmic perspective on the origin of life. Hoyle and wickramasinghe in a series of publications have argued that dust grains in interstellar clouds contain bacteria and that the disruption of bio-grains in the presence of a UV flux is responsible for the large scale presence of Polycyclic Aromatic Hydrocarbons and other organic polymers. In the present communication it is proposed that proteins and polypeptides will also result in the disruptions of bacteria in the interstellar clouds. These polypeptides have characteristic vibrational modes of the amide group in the polymer chain. The observational regions in the infrared for the amide modes of α helical polypeptides is suggested. Since amino acids appearing on disruptions of biotic matter may be predominantly in polymeric form and rotational transitions would not occur, their vibrational transitions are of significant importance. Thus infrared spectroscopy of circumstellar shells and dense clouds in the star forming regions for the amide bands in the 2.5 to 18 μm IR range would play a decisive role in the theories of interstellar biomolecules.