| Abstract | dc.description.abstract | The definition of life has excited little interest among molecular biologists during the past
half-century, and the enormous development in biology during that time has been largely
based on an analytical approach in which all biological entities are studied in terms of their
components, the process being extended to greater and greater detail without limit. The
benefits of this reductionism are so obvious that they need no discussion, but there have
been costs as well, and future advances, for example for creating artificial life or for taking
biotechnology beyond the level of tinkering, will need more serious attention to be given to
the question of what makes a living organism living. According to Robert Rosen’s theory of
(M,R)-systems (metabolism-replacement systems), the central idea missing from molecular
biology is that of metabolic circularity, most evident from the obvious but commonly
ignored fact that proteins are not given from outside but are products of metabolism,
and thus metabolites. Among other consequences this implies that the usual distinction
between proteome and metabolome is conceptually artificial—however useful it may be in
practice—as the proteome is part of the metabolome. | en_US |
