Braess' Paradox in Enzyme Kinetics: Asymmetry from Population Balance without Direct Cooperativity.

ABSTRACT: The ATPase ABCE1, a member of the ubiquitous ATP-Binding Cassette protein superfamily, is essential in eukaryotic and archaeal ribosome recycling. It comprises a pair of homologous nucleotide-binding domains (NBDs), each containing a consensus nucleotide-binding site (NBS), where ATP hydrolysis takes place. Each of these sites can be in either an open or closed conformation. Despite the near symmetry of the two NBDs, and quite unexpectedly, their hydrolysis kinetics are highly asymmetric. While substitution of the catalytic glutamate (E238Q) in NBSI reduced the overall turnover rate of the ATPase by a factor of 2, as one might expect, the corresponding substitution in NBSII (E485Q) shows a so far unexplained 10-fold increase. To address this issue, we used Markov models to study how such a

SUBMITTER: Schaffner M 

PROVIDER: S-EPMC12937102 | biostudies-literature | 2026 Feb

REPOSITORIES: biostudies-literature