Pasteurella multocida toxin activates various heterotrimeric G proteins by deamidation.

ABSTRACT: Pasteurella multocida produces a 146-kDa protein toxin (Pasteurella multocida toxin, PMT), which stimulates diverse cellular signal transduction pathways by activating heterotrimeric G proteins. PMT deamidates a conserved glutamine residue of the ?-subunit of heterotrimeric G proteins that is essential for GTP-hydrolysis, thereby arresting the G protein in the active state. The toxin substrates are G?(q) G?(13) and the G?(i)-family proteins. Activation of these ?-subunits causes stimulation of phospholipase C?, Rho-guanine nucleotide exchange factors or inhibition of adenylyl cyclase. This article provides the current knowledge on PMT concerning the structure-function analysis based on the crystal structure and recently elucidated molecular mode of action. Furthermore, the impact of PMT on cellular signaling is discussed.

SUBMITTER: Orth JH 

PROVIDER: S-EPMC3202810 | biostudies-literature | 2010 Feb

REPOSITORIES: biostudies-literature