title: Construction and characterization of a cheA mutant of Treponema denticola.
abstract: The Treponema denticola cheA gene, encoding the central kinase of the general chemotaxis pathway, was analyzed for its role in chemotaxis and tissue penetration. The cheA gene was interrupted by insertion of an ermF-ermAM gene cassette. Reverse transcription-PCR confirmed that the other downstream chemotaxis genes within the same operon (cheW, cheX, and cheY) were still expressed in the cheA mutant strain. Lack of cheA resulted in decreased swarming on soft-agar swarm plates and failure to respond chemotactically to a mixture of nutrients. Behavioral analyses using video microscopy revealed that the cheA mutant exhibited coordinated cell movement. The cellular reversal frequency, however, was severely reduced, indicating that CheA in T. denticola mainly controls cellular reversal and that active chemotaxis signaling input is not required for coordination of flagellar rotation at both cell poles.
authors: School of Dentistry and Molecular Biology Institute, University of California, Los Angeles, California 90095-1668, USA.
authors: Renate
authors: R
authors: Lux
authors: Jee-Hyun
authors: JH
authors: Sim
authors: Jon P
authors: JP
authors: Tsai
authors: Wenyuan
authors: W
authors: Shi
mesh_terms: D001426:Bacterial Proteins; D002633:Chemotaxis / Q000235:genetics; D005798:Genes, Bacterial; D008565:Membrane Proteins / Q000235:genetics*; D000072236:Methyl-Accepting Chemotaxis Proteins; D009068:Movement; D016254:Mutagenesis, Insertional; D014208:Treponema / Q000201:enzymology*
chemical_list: D001426:Bacterial Proteins; D008565:Membrane Proteins; D000072236:Methyl-Accepting Chemotaxis Proteins