Involved in chemotaxis. Part of a chemotaxis signal transduction system that modulates chemotaxis in response to various stimuli. Catalyzes the demethylation of specific methylglutamate residues introduced into the chemoreceptors (methyl-accepting chemotaxis proteins or MCP) by CheR. Also mediates the irreversible deamidation of specific glutamine residues to glutamic acid. [protein]-L-glutamate 5-O-methyl ester + H2O = H(+) + L-glutamyl-[protein] + methanol H2O + L-glutaminyl-[protein] = L-glutamyl-[protein] + NH4(+) Contains a C-terminal catalytic domain, and an N-terminal region which modulates catalytic activity. Phosphorylated by CheA. Phosphorylation of the N-terminal regulatory domain activates the methylesterase activity. P.putida strain KT2440 does not have a chemotaxis group 2 operon. Belongs to the CheB family.