Stress physiology in Azospirillum and other PGPRs

Abstract

Rhizobacteria are constantly faced with environmental stimuli stresses and should be responding to a wide range of factors through signal transduction pathways that convert extracellular information into intracellular forms. The cytoplasmic membrane of bacteria is permeable to water but forms an effective barrier for most solute present in the cytoplasmic. To survive osmotic stresses, rhizobacteria need to adapt by accumulating specific solutes under hyperosmotic conditions and releasing them under hyposmotic conditions. These solutes are referred to compatible solutes and glutamate, K+, trehalose, betaine, among others solutes, are used to response. But new studies to proteins, phospholipids, and polysaccharides and their pattern in response to stress are necessary.