We establish an appropriate thermodynamic framework for determining the optimal genome length in electrostatically driven viral encapsidation. Importantly, our analysis includes the electrostatic potential due to the Donnan equilibrium, which arises from the semipermeable nature of the viral capsid, i.e., permeable to small mobile ions but impermeable to charged macromolecules. Because most mac...

1. Colloids have been divided into two groups according to the ease with which their solutions or suspensions are precipitated by electrolytes. One group (hydrophilic colloids), e.g., solutions of gelatin or crystalline egg albumin in water, requires high concentrations of electrolytes for this purpose, while the other group (hydrophobic colloids) requires low concentrations. In the latter grou...

An answer has been given by Hitchcock 1 to a recent criticism by myself 2 of an argument vigorously exploited by Loeb in favor of his theory of colloidal behavior. Hitchcock suggests that this criticism rests upon a misunderstanding, but he admits the validity of my main contentions, and I am happy to note that Loeb has taken heed of them in two recent papers. I have no quarrel with many of the...

1. A comparative study has been made of the diffusibility of calcium in solutions of crystalline egg albumin, serum globulin, and human blood serum. 2. In all three of these solutions, at pH 7.4, molal Ca concentrations within the membrane are greater than the calcium concentrations in the outside solutions, quite in accordance with the Donnan theory. 3. At pH 7.4, the ratio of See PDF for Stru...

There is no real point of conflict between our views and those expressed by Professor Hill. The mere agreement of the figures for P.D., considered abstractly and apart from experimental conditions, is not a proof of the existence of a Donnan equilibrium. For example, in an experiment in which the protein were omitted altogether there would also be agreement of the r.D. values, for each would be...

The ratio of concentration of chloride in the aqueous humor compared with that in the plasma of rabbits, dogs, and human beings, was determined by the Schales and Sendroy methods. Consistent results were obtained in all the experiments by the Schales method with or without protein, and by the Sendroy method without protein. In the presence of protein, however, lower chloride concentrations were...

The curvature stress of DNA packed inside a phage is balanced against its electrostatic self-interaction. The DNA density is supposed nonuniform and as a result the Donnan effect is also inhomogeneous. The coarse-grained DNA density is a nonlinear function of the DNA radius of curvature at a given position inside the bacteriophage. It turns out that a region (or regions) exists totally free fro...