Role of Che Y Protein in the Bacterial Chemosensory
Information Processing Pathway.
Che Y mutants lack all sensory response to chemo-attractants or repellants
indicating a central role of Che Y in the sensory information pathway. Second site
suppressors of Che Y isolated in Fla A locus indicating suggest some type of interaction
between Che Y and the flagellar machinery. Che Y overexpression studies in strains
deleted for Che A, Che B, Che W, Che R, Che Y and Che Z indicate that Che Y gene
product is sufficient to cause tumbling.
Strains lacking in chemo-receptors show
tumbling movements on Che Y overexpression. Reversal of tumbling by Che Y overexpression required requires the presence of the other Che gene products. Didn’t you just
say the opposite above?
This suggests that these genes may be intermediates in
communication between chemo-receptors and Che Y – flagellar machinery interaction.
(The key thing is that these experiments show that CheY acts after the other (known) Che
proteins in the pathway.)