In bacterial chromosome segregation, ParA is responsible for:
In tripartite ParABS chromosome segregation ParA role dynamic scaffolding providing motive force. ParA proteins family Walker A ATPase dimerize upon ATP binding forming DNA binding competent form coating bacterial chromosome as cargo independent cloud. Upon ATP hydrolysis to ADP affinity for DNA drops, detachment occurs. ParB parS partition complex stimulates ATPase converting ParA ATP to ADP, so region behind moving complex depleted ParA, while front retains high concentration. Newly synthesized ParA ATP rebinds nucleoid generating gradient that directs chemophoretic movement of ParB parS ori
Ref: Lutkenhaus, Annu Rev Biochem, 2020, ParA filament formation pulling chromosomes apart during segregation.
