Characterization and properties of intracellular proteins after cold acclimation of the ice-nucleating bacterium Pantoea agglomerans (Erwinia herbicola) IFO12686

The ice-nucleating bacterium Pantoea agglomerans (Erwina herbicola) IF01268 6 (INA(+)) responds to a decrease in temperature by the induction of protei ns. The pattern of protein bands from strain IF012686 following a shift in temperature From 30 to 12 degreesC could be divided into four major groups: (1) increasing protein bands. (2) decreasing protein bands. (3) increasing -decreasing protein bands, and (4) almost constant protein bands. We identi fied a cryoprotective function in the increasing protein band round in stra in IF012686. The increasing protein bands that followed a reduction in temp erature were considered to have an important role in cold acclimation or ad aptation. We showed that these proteins possessed cryoprotective activity w hen tested against the freeze-labile enzyme lactate dehydrogenase. The stra in IF012686 had greater cryotolerance than Pa. agglomerans IAM1595 (INA ). and the degree of cryotolerance was increased by cold acclimation. (C) 2000 Academic Press.