Barrett S. Perchuk

TL;DR: A system-level investigation of two-component pathways in the model organism Caulobacter crescentus is reported and a new, highly conserved essential signaling pathway from the histidine kinase CenK to the response regulator CenR is identified, which plays a critical role in controlling cell envelope biogenesis and structure.

TL;DR: A single integrated circuit whose components and connectivity can account for the cell cycle oscillations of CtrA in Caulobacter is defined.

TL;DR: It is proposed that the abundance of promiscuous variants promotes the expansion and diversification of toxin-antitoxin systems and other paralogous protein families during evolution.

TL;DR: The results begin to reveal the molecular mechanism by which a small set of amino acids enables an individual kinase to discriminate amongst a large set of highly-related response regulators and vice versa.

TL;DR: The divergent evolution of a model bacterial signaling pathway comprising the kinase PhoR and its cognate substrate PhoB is examined, showing that the specificity-determining residues of these proteins are typically under purifying selection but have, in α-proteobacteria, undergone a burst of diversification followed by extended stasis.