Fig. 2: Cryo-EM structural models reveal active and inactive conformations in the proteasome core particle.
From: Structural basis for allosteric modulation of M. tuberculosis proteasome core particle
a Superimposing one α/β-pair from each cryo-EM structure revealed little difference across the α-subunits from each variant but highlighted a key shift in the β-subunit of 20SβT1A where the switch helix I shifts by ~4 degrees and 4.7 Å (measured from Cα of βA49) compared to the other three variants. b This movement shifts an upstream loop and β-strand, collapsing the S1 pocket and preventing substrate binding. c Residues forming the back of the S1 pocket, βA46, βG47, βT48 and βA49, move up to 3 Å between the 20SWT and 20SβT1A variants when comparing the Cα of the respective residue to the Cα of βT1 or βK33 of the catalytic triad. Source data are provided as a Source Data file.
