Involvement of plasma membrane calcium influx in bacterial induction of the K super(+)/H super(+) and hypersensitive responses in tobacco

An early event in the hypersensitive response of tobacco to Pseudomonas syringae pv syringae is the initiation of a K super(+)/H super(+) response characterized by specific plasma membrane K super(+) efflux, extracellular alkalinization, and intracellular acidification. We investigated the role of calcium in induction of these host responses. We conclude that increased plasmalemma Ca super(2+) influx is required for the K super(+)/H super(+) and hypersensitive responses in tobacco.