Forms membrane-associated dynamic filaments that are essential for cell shape determination (PubMed:15612918, PubMed:21903929). Acts by regulating cell wall synthesis and cell elongation, and thus cell shape (PubMed:21903929). A feedback loop between cell geometry and MreB localization maintains elongated cell shape by targeting cell wall growth to regions of negative cell wall curvature (PubMed:24550515). Filaments rotate around the cell circumference in concert with the cell wall synthesis enzymes. The process is driven by the cell wall synthesis machinery and does not depend on MreB polymerization (PubMed:21903929). Rotation may contribute to the robust maintenance of rod shape (PubMed:21903929). Requires ATP hydrolysis for polymerization (PubMed:23235161). Polymerization is inhibited by toxins CbtA and CptA, as well as by A22 ([S-(3,4-dichlorobenzyl)isothiourea)] all of which cause cell rounding and eventual death. Inhibition by toxin CbtA is neutralized by cytoskeleton bundling-enhancing protein CbeA, inhibition by toxin CptA is neutralized by antitoxin CptB, while inhibition by A22 can be neutralized by overexpression of CbeA (PubMed:21166897, PubMed:22239607, PubMed:22515815). Forms polymers in the presence of ATP or GTP (PubMed:23235161). Forms an essential membrane-bound complex with MreC and MreD. Interacts directly with MreC but not with MreD (PubMed:15612918). Interacts with FtsZ, toxins CbtA and CptA, and cytoskeleton bundling-enhancing protein CbeA (PubMed:21166897, PubMed:22239607, PubMed:22515815). Membrane-associated (PubMed:15612918). Preferentially localizes to regions of negative curvature (PubMed:24550515). May associate with the membrane via MreC (PubMed:15612918). Localization depends on MreC, MreD and RodA (PubMed:15612918). Depletion results in enlarged, spherical cells. Belongs to the FtsA/MreB family. Extended N-terminus.