The DinI and RecX proteins of Escherichia coli both modulate the function of RecA protein, but have very different effects. DinI protein stabilizes RecA filaments, preventing disassembly but permitting assembly. RecX protein blocks RecA filament extension, which can lead to net filament disassembly. We demonstrate that both proteins can interact with the RecA filament, and propose that each can...

RecA protein plays a principal role in bacterial SOS response to DNA damage. The induction of the SOS response is well understood and involves the cleavage of the LexA repressor catalyzed by the RecA nucleoprotein filament. In contrast, our understanding of the regulation and termination of the SOS response is much more limited. RecX and DinI are two major regulators of RecA's ability to promot...

When DinI is present at concentrations that are stoichiometric with those of RecA or somewhat greater, DinI has a substantial stabilizing effect on RecA filaments bound to DNA. Exchange of RecA between free and bound forms was almost entirely suppressed, and highly stable filaments were documented with several different experimental methods. DinI-mediated stabilization did not affect RecA-media...

The Escherichia coli RecA protein triggers both DNA repair and mutagenesis in a process known as the SOS response. The 81-residue E. coli protein DinI inhibits activity of RecA in vivo. The solution structure of DinI has been determined by multidimensional triple resonance NMR spectroscopy, using restraints derived from two sets of residual dipolar couplings, obtained in bicelle and phage media...

Dini derivative on Riemannian manifold setting is studied in this paper. In addition, a characterization for Lipschitz and convex functions defined on Riemannian manifolds and sufficient optimality conditions for constraint optimization problems in terms of the Dini derivative are given.

The primary goal of this paper is to furnish an alternative description for the contingent normal cone, similar to the one that exists for the Fréchet one, but by using a directional convergence in place of the usual one. In fact, we actually prove that the same description is available not only for the contingent normal cone, but also for the Dini-Hadamard normal cone and the Dini-Hadamard-lik...

In this paper we consider nonautonomous optimal control problems of infinite horizon type, whose control actions are given by L-functions. We verify that the value function is locally Lipschitz. The equivalence between dynamic programming inequalities and HJB inequalities for proximal sub (super) gradients is proven. Using this result we show that the value function is a Dini solution of the HJ...

The SOS response, a set of cellular phenomena exhibited by eubacteria, is initiated by various causes that include DNA damage-induced replication arrest, and is positively regulated by the co- protease activity of RecA. Escherichia coli DinI, a LexA-regulated SOS gene product, shuts off the initiation of the SOS response when overexpressed in vivo. Biochemical and genetic studies indicated that...

In Escherichia coli, the SOS response is induced upon DNA damage and results in the enhanced expression of a set of genes involved in DNA repair and other functions. The initial step, self-cleavage of the LexA repressor, is promoted by the RecA protein which is activated upon binding to single-stranded DNA. In this work, induction of the SOS response by the addition of mitomycin C was found to ...