We report results of evaluation of several measures of chemical disequilibrium in living and abiotic systems. The previously defined measures include RT and RL, which are Euclidean distances of a coarse grained polymer length distribution from two different chemical equilibrium states associated with equilibration to an external temperature bath and with isolated equilibration to a distribution determined by the bond energy of the system, respectively. The determination uses a simplified description of the energetics of the constituent molecules. We evaluated the measures for data from the ribosome of E. coli, a variety of yeast, and the proteomes (with certain assumptions) of a large family of prokaryotes, and for mass spectrometric data from the atmosphere of the Saturn satellite Titan and for nonliving commercial copolymers. We find with surprising consistency that RL is much smaller than RT for all these systems. The living (protein) systems have a well defined value of RT that is sharply defined and distinct from that obtained from the nonliving Titan and copolymer systems. The living systems are also distinguishably characterized by larger values of RL than most of the nonliving systems, but RL values vary more from one living system to another than the RT values do. These data suggest that the measures RL and RT can distinguish living from nonliving systems.
Bibliographical noteFunding Information:
This work was supported by the United States National Aeronautics and Space Administration (NASA) through Grant No. NNX14AQ05G and used the computational resources of the Minnesota Supercomputing Institute, the Open Science Grid, the University of Minnesota School of Physics and Astronomy Condor cluster, and the NASA Advanced Supercomputing division Pleiades supercomputer. We thank Aaron Wynveen for helpful discussions and Ravindra Desai, Joao Paulo, Bastian Staal, Gabriel Vivo Truyola, and Niels Fischer for answering questions about their work and supplying us with their data. The Titan data are available on NASA's Planetary Database System, as well as in summary form, in Ref. .
© 2019 American Physical Society.
Copyright 2019 Elsevier B.V., All rights reserved.