NahY, a catabolic plasmid-encoded receptor required for chemotaxis of Pseudomonas putida to the aromatic hydrocarbon naphthalene

Pseudomonas putida G7 exhibits chemotaxis to naphthalene, but the molecular basis for this was wt known. A new gene, nahY, was found to be cotranscrib ed,vith meta cleavage pathway genes on the NAH7 catabolic plasmid for napht halene degradation, The nahY gene encodes a 538-amino-acid protein with a m embrane topology and a C-terminal region that resemble those of chemotaxis transducer proteins. AP. putida G7 nahY mutant grew on naphthalene but was not chemotactic to this aromatic hydrocarbon. The protein NahY thus appears to function as a chemoreceptor for naphthalene or a related compound. The presence of nahY on a catabolic plasmid implies that chemotaxis may facilit ate biodegradation.