The conformational landscape of fold-switcher KaiB is tuned to the circadian rhythm timescale.

ABSTRACT: How can a single protein domain encode a conformational landscape with multiple stably-folded states, and how do those states interconvert? Here, we use real-time and relaxation-dispersion NMR to characterize the conformational landscape of the circadian rhythm protein KaiB from Rhodobacter sphaeroides. Unique among known natural metamorphic proteins, this KaiB variant spontaneously interconverts between two monomeric states: the "Ground" and "Fold-switched" (FS) state. KaiB in its FS state interacts with multiple binding partners, including the central KaiC protein, to regulate circadian rhythms. We find that KaiB itself takes hours to interconvert between the Ground and FS state, underscoring the ability of a single sequence to encode the slow process needed for function. We revea

SUBMITTER: Wayment-Steele HK 

PROVIDER: S-EPMC11185700 | biostudies-literature | 2024 Jun

REPOSITORIES: biostudies-literature