Using CEST NMR to discover previously unobserved states on the free energy surface of proteins: Application to the L99A cavity mutant of T4 lysozyme.

ABSTRACT: Carr-Purcell-Meiboom-Gill (CPMG) relaxation dispersion experiments establish that at room temperature, the L99A cavity mutant of T4 lysozyme (L99A T4L) interconverts between two compact folded conformations on the millisecond timescale. These include the native state in which the sidechain of Phe114 is exposed to solvent (E state) and a near-native minor state in which the aromatic moiety of Phe114 is buried in the core of the protein (B state, ∼2%). Molecular dynamics simulations that have captured the E to B interconversion in L99A T4L and related mutants suggest that these proteins adopt compact folded conformations other than E and B, yet extensive CPMG studies have not detected such states. In an effort to detect these more elusive conformers experimentally, we have recorded Chemical

SUBMITTER: Tiwari VP 

PROVIDER: S-EPMC12805379 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature