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Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
MeSH Review


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High impact information on Entropy

  • Some partitioning processes, particularly involving polymeric solvents such as octanol or hexadecane, are governed not only by translational entropies and contact interactions, but also by free energies resulting from changes in the conformations of the polymer chains upon solute insertion [1].
  • Enthalpies and entropies have been determined for the reversible binding of O2 and CO to chelated protoheme, a compound having a covalently attached imidazole bound to the iron [2].
  • At 25 degrees the binding of NADPH and NADP+ is characterized by small negative enthalpies and large positive entropies whereas the binding of the folates and methotrexate is accompanied by large negative enthalpies and small negative entropies [3].
  • Temperature effects on the catalytic activity of the D38E mutant of 3-oxo-Delta5-steroid isomerase: favorable enthalpies and entropies of activation relative to the nonenzymatic reaction catalyzed by acetate ion [4].
  • Experimental differential entropies of hydration were found to be of the order of -20 cal/mol/K although values vary from system to system [5].

Biological context of Entropy

  • The thermal inactivation of ISVPs approximated first-order kinetics over a range of temperatures, permitting the use of Arrhenius plots to estimate activation enthalpies and entropies that account for the different behaviors of T1L and T3D [6].
  • Partition properties, that is partition coefficients and enthalpies (delta Hp degree) and entropies (delta Sp degree) of partition, have been measured for 50 benzoic acids in the 1-octanol/water system, and their role in QSAR (quantitative structure-activity relationship) analysis examined [7].
  • Acceleration of either acetyl phosphate or ATP hydrolysis rates was promoted by a decrease in both activation energies (Ea) and in entropies of activation delta S [8].
  • This article evaluates the differences in using heart rate versus heart period to estimate fractal dimensions and approximate entropies of these time series [9].

Anatomical context of Entropy


Associations of Entropy with chemical compounds

  • Enthalpies and entropies for ferric ion binding were determined from calorimetric measurements [12].
  • Activation enthalpies and entropies for the microscopic rate constants of acetate-catalyzed isomerization of 5-androstene-3,17-dione [13].
  • Dissociation thresholds of 1.17 and 1.09 eV and activation entropies of -22.2 and -23.3 cal/(mol K) were obtained for des-Arg(1) and des-Arg(9)-bradykinin from RRKM modeling of time-resolved data [14].
  • Azide and thiocyanate bind trans to a thiolate, and with similar entropies and enthalpies (thiocyanate: DeltaH = -7.5 +/- 1.1 kcal/mol, DeltaS = -17.2 +/- 3.2 eu; azide: DeltaH = -6.5 +/- 1.0 kcal/mol, DeltaS = -12.6 +/- 2.4 eu) [15].
  • In addition, we assessed the "proline effect" on the conformational equilibria by comparing the differences in configurational entropies between the reverse turn and extended conformations of the two peptides [16].

Gene context of Entropy

  • Thermodynamic coupling of cap-eIF4E association to intramolecular self-stacking of dinucleotide cap analogues strongly influences the enthalpies and entropies of the binding, but has a negligible effect on the resultant DeltaG degrees and DeltaC(p) degrees values [17].
  • The spectral entropies show distinctly lower structural ordering for psiEst-6 than for Est-6 in all species studied [18].
  • Using 3,3',4,4'-tetrachlorobiphenyl (TCB) as the reference compound, it is shown that PCBs having higher electron affinities, lower lipophilicities and entropies than TCB are potent ligands for rat hepatic AhR [19].
  • The models show that lipophilicities, electron affinities, entropies and electronic energy gaps of PCBs are key physicochemical properties controlling their AhR, AHH and EROD activities [19].
  • The relative enthalpies at 0 K and relative free energies at 298 K were based on the above-mentioned relative energies and zero-point vibration energies, temperature-dependent enthalpy terms and entropies evaluated at the MP2/6-31G level [20].

Analytical, diagnostic and therapeutic context of Entropy


  1. Solvation: how to obtain microscopic energies from partitioning and solvation experiments. Chan, H.S., Dill, K.A. Annual review of biophysics and biomolecular structure. (1997) [Pubmed]
  2. Binding of O2 and CO to hemes and hemoproteins. Traylor, T.G., Berzinis, A.P. Proc. Natl. Acad. Sci. U.S.A. (1980) [Pubmed]
  3. Interaction of methotrexate, folates, and pyridine nucleotides with dihydrofolate reductase: calorimetric and spectroscopic binding studies. Subramanian, S., Kaufman, B.T. Proc. Natl. Acad. Sci. U.S.A. (1978) [Pubmed]
  4. Temperature effects on the catalytic activity of the D38E mutant of 3-oxo-Delta5-steroid isomerase: favorable enthalpies and entropies of activation relative to the nonenzymatic reaction catalyzed by acetate ion. Houck, W.J., Pollack, R.M. J. Am. Chem. Soc. (2004) [Pubmed]
  5. Sequential hydration of small protonated peptides. Liu, D., Wyttenbach, T., Barran, P.E., Bowers, M.T. J. Am. Chem. Soc. (2003) [Pubmed]
  6. Thermostability of reovirus disassembly intermediates (ISVPs) correlates with genetic, biochemical, and thermodynamic properties of major surface protein mu1. Middleton, J.K., Severson, T.F., Chandran, K., Gillian, A.L., Yin, J., Nibert, M.L. J. Virol. (2002) [Pubmed]
  7. Energy aspects of oil/water partition leading to the novel hydrophobic parameters for the analysis of quantitative structure-activity relationships. Da, Y.Z., Ito, K., Fujiwara, H. J. Med. Chem. (1992) [Pubmed]
  8. Role of water activity on the rates of acetyl phosphate and ATP hydrolysis. de Meis, L., Suzano, V.A. FEBS Lett. (1988) [Pubmed]
  9. Fractal dimension and approximate entropy of heart period and heart rate: awake versus sleep differences and methodological issues. Yeragani, V.K., Sobolewski, E., Jampala, V.C., Kay, J., Yeragani, S., Igel, G. Clin. Sci. (1998) [Pubmed]
  10. Kinetic studies of actinomycin D binding to mono-, oligo-, and polynucleotides. Brown, S.C., Shafer, R.H. Biochemistry (1987) [Pubmed]
  11. A comparison between adenylate cyclase solubilized from normal and Rous sarcoma virus-transformed chicken embryo fibroblasts. Gidwitz, S., Toscano, W.A., Toscano, D.G., Weber, M.J., Storm, D.R. Biochim. Biophys. Acta (1980) [Pubmed]
  12. Iron-sulfur cluster biosynthesis. Characterization of frataxin as an iron donor for assembly of [2Fe-2S] clusters in ISU-type proteins. Yoon, T., Cowan, J.A. J. Am. Chem. Soc. (2003) [Pubmed]
  13. Activation enthalpies and entropies for the microscopic rate constants of acetate-catalyzed isomerization of 5-androstene-3,17-dione. Houck, W.J., Pollack, R.M. J. Am. Chem. Soc. (2003) [Pubmed]
  14. Shattering of Peptide ions on self-assembled monolayer surfaces. Laskin, J., Bailey, T.H., Futrell, J.H. J. Am. Chem. Soc. (2003) [Pubmed]
  15. Why is there an "inert" metal center in the active site of nitrile hydratase? Reactivity and ligand dissociation from a five-coordinate Co(III) nitrile hydratase model. Shearer, J., Kung, I.Y., Lovell, S., Kaminsky, W., Kovacs, J.A. J. Am. Chem. Soc. (2001) [Pubmed]
  16. Reverse turns in blocked dipeptides are intrinsically unstable in water. Tobias, D.J., Sneddon, S.F., Brooks, C.L. J. Mol. Biol. (1990) [Pubmed]
  17. Thermodynamics of mRNA 5' cap binding by eukaryotic translation initiation factor eIF4E. Niedzwiecka, A., Darzynkiewicz, E., Stolarski, R. Biochemistry (2004) [Pubmed]
  18. Entropy and GC Content in the beta-esterase gene cluster of the Drosophila melanogaster subgroup. Balakirev, E.S., Chechetkin, V.R., Lobzin, V.V., Ayala, F.J. Mol. Biol. Evol. (2005) [Pubmed]
  19. Affinities for the aryl hydrocarbon receptor, potencies as aryl hydrocarbon hydroxylase inducers and relative toxicities of polychlorinated biphenyls. A congener specific approach. Kafafi, S.A., Afeefy, H.Y., Ali, A.H., Said, H.K., Abd-Elazem, I.S., Kafafi, A.G. Carcinogenesis (1993) [Pubmed]
  20. Correlated ab initio study of nucleic acid bases and their tautomers in the gas phase, in a microhydrated environment and in aqueous solution. guanine: surprising stabilization of rare tautomers in aqueous solution. Hanus, M., Ryjácek, F., Kabelác, M., Kubar, T., Bogdan, T.V., Trygubenko, S.A., Hobza, P. J. Am. Chem. Soc. (2003) [Pubmed]
  21. Phase behavior of artificial stratum corneum lipids containing a synthetic pseudo-ceramide: a study of the function of cholesterol. Mizushima, H., Fukasawa, J., Suzuki, T. J. Lipid Res. (1996) [Pubmed]
  22. Kulback-Leibler and renormalized entropies: applications to electroencephalograms of epilepsy patients. Quiroga, R.Q., Arnhold, J., Lehnertz, K., Grassberger, P. Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics. (2000) [Pubmed]
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