The mutant cIts genes from seven different lambdacIts phages carrying tsU50, tsU9, tsU46, ts1, tsU51, tsI-22 and ts2 mutations were cloned in plasmid. The positions of these mutations and the resulting changes of amino acids in the repressor were determined by DNA sequencing. The first four mutations mapping in the N-terminal domain show the following changes: I21S, G53S, A62T and V73A, respect...

Counterion-induced inversion of the DNA charge was characterized through extensive molecular dynamics simulations. We observed reversal of the DNA motion in an external electric field upon increasing the concentration of trivalent or quadrivalent counterions. In the case of a divalent electrolyte, inversion of the DNA's electric charge was observed at high concentrations of the electrolyte but ...

'N a recent paper' the question has been raised as ~ to whether the weak interactions are invariant under a space inversion. It was also pointed out there that similar to the situation for space inversion there exists at present no experimental proof that weak interactions are invariant under charge conjugation. Consequently the absolute invariance under charge conjugation is also an open quest...

Extensive Monte Carlo simulations and scaling arguments are used to study the colloidal charge reversal. The critical colloidal surface charge density sigma(c) at which the reversal first appears is found to depend strongly on the ionic size. We find that sigma(c) has an inflection point as a function of the electrolyte concentration. The width of the plateau region in the vicinity of the infle...

Human cytidine deaminase APOBEC3G and the virion infectivity factor (vif) of the human immunodeficiency virus (HIV) are a pair of antagonistic molecules. In the absence of vif, APOBEC3G induces a high rate of dC to dU mutations in the nascent reverse transcripts of HIV that leads to the degradation of the HIV genome. HIV vif, on the other hand, can suppress the translation and trigger the degra...

1. Trivalent cations cause a collodion membrane covered with a protein film to be charged positively while they do not produce such an effect on collodion membranes not possessing a protein film. The same had been found for the reversal of the sign of charge of the membrane by acid. 2. This reversal in the sign of charge of the membrane by trivalent cations occurs on the alkaline side of the is...

Bilayer vesicles form readily from mixtures of charged and neutral surfactants. When such a mixed vesicle binds an oppositely charged object, its membrane partially demixes: the adhesion zone recruits more charged surfactants from the rest of the membrane. Given an unlimited supply of adhering objects one might expect the vesicle to remain attractive until it was completely covered. Contrary to...

Smoluchowski equation and the Monte Carlo simulations are used to study the conditions leading to the reversal of the electrophoretic mobility. Zeta (zeta) potential is identified with the diffuse potential at the shear plane which, we argue, must be placed at least one ionic diameter away from the colloidal surface. For sufficiently strongly charged colloids, zeta potential changes sign as a f...