Pseudomonas aeruginosa Exotoxin A: Structure/Function, Production, and Intoxication of Eukaryotic Cells

Abstract

Exotoxin A (ETA) is the most toxic of the numerous extracellular proteins (LasA and LasB elastases, alkaline protease, protease IV, hemolytic and non-hemolytic phospholipase C, exoenzyme S, and cytotoxin) produced by the opportunistic pathogen Pseudomonas aeruginosa. ETA belongs to a class of secreted bacterial toxins that transfer the adenosine diphosphate (ADP)—ribose moiety of nicotinamide adenine dinucleotide cation (NAD+) to specific target proteins within eukaryotic cells (Krueger and Barbieri 1995). ETA, like many of these toxins, conforms to a simple A—B structure—function model in which the A domain possesses enzymatic activity and the B domain binds to a specific receptor on the surface of target cells.