Sensitivity of OR in phage lambda.

Audun Bakk; Ralf Metzler; Kim Sneppen

doi:10.1016/s0006-3495(04)74083-7

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Sensitivity of OR in phage lambda.

Audun Bakk·Ralf Metzler·Kim Sneppen

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Abstract

We investigate the sensitivity of the right operator in bacteriophage lambda. In particular, the system is probed in the three different regulatory protein concentration-regimes: 1), lysogen (CI dominates); 2), during induction (CI and Cro at comparable concentrations); and 3), after induction (Cro dominates). Systematic perturbations of the protein-operator binding energies show in a lysogen that the activity (production rate) at promoter PRM is robust to variations, in contrast to PR, where the sensitivity is high. Both promoters, however, show large sensitivity in regimes 2 and 3. In all regimes we identify several suppressors, meaning that for a given large perturbation (+/-2 kcal/mol) of one binding energy, there exist compensating perturbation(s) that restore the wild-type activity.

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Bacteriophage lambda Binding Sites Computer Simulation DNA-Binding Proteins DNA-Directed RNA Polymerases Enzyme Activation Kinetics Models, Chemical Operator Regions, Genetic Promoter Regions, Genetic Protein Binding Protein Structure, Tertiary Repressor Proteins Sensitivity and Specificity Viral Proteins Viral Regulatory and Accessory Proteins Comparative Study Evaluation Study Journal Article

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Audun Bakk, Ralf Metzler, Kim Sneppen. 2004. Sensitivity of OR in phage lambda.. https://doi.org/10.1016/s0006-3495(04)74083-7

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