Single molecule turnover of fluorescent ATP by myosin and actomyosin unveil elusive enzymatic mechanisms.

ABSTRACT: Benefits of single molecule studies of biomolecules include the need for minimal amounts of material and the potential to reveal phenomena hidden in ensembles. However, results from recent single molecule studies of fluorescent ATP turnover by myosin are difficult to reconcile with ensemble studies. We found that key reasons are complexities due to dye photophysics and fluorescent contaminants. After eliminating these, through surface cleaning and use of triple state quenchers and redox agents, the distributions of ATP binding dwell times on myosin are best described by 2 to 3 exponential processes, with and without actin, and with and without the inhibitor para-aminoblebbistatin. Two processes are attributable to ATP turnover by myosin and actomyosin respectively, whereas the remaining pr

SUBMITTER: Usaj M 

PROVIDER: S-EPMC7806905 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature