Pollack M
Rev Infect Dis. 1983 Nov-Dec;5 Suppl 5:S979-84. doi: 10.1093/clinids/5.supplement_5.s979.
Exotoxin A is an extracellular enzyme that is produced by most clinical strains of Pseudomonas aeruginosa. It is a single-chain polypeptide (molecular weight, 71,000) with A and B fragments that mediate enzymatic and cell-binding functions, respectively. Exotoxin A catalyzes the transfer of the adenosine diphosphate-ribosyl moiety from nicotinamide-adenine dinucleotide to elongation factor 2, which results in the inactivation of the latter and the inhibition of protein biosynthesis. Exotoxin A is a potent cytotoxin and is lethal for a variety of animals, including subhuman primates. Produced in vivo during P. aeruginosa infections, exotoxin A apparently causes disease by inhibition of protein synthesis, direct cytopathic effects, and interference with cellular immune functions of the host. Antibodies to exotoxin A provide protection from some of the biochemical, pathologic, and lethal consequences of both experimental and clinical pseudomonas infections. Toxoid produced from exotoxin A is currently undergoing evaluation as a vaccine for possible use in the immunoprophylaxis against pseudomonas disease in humans.
外毒素A是一种细胞外酶，由大多数铜绿假单胞菌临床菌株产生。它是一种单链多肽（分子量为71,000），具有A和B片段，分别介导酶促和细胞结合功能。外毒素A催化烟酰胺腺嘌呤二核苷酸的腺苷二磷酸核糖基部分转移至延伸因子2，导致后者失活并抑制蛋白质生物合成。外毒素A是一种强效细胞毒素，对包括非人灵长类动物在内的多种动物具有致死性。在铜绿假单胞菌感染期间于体内产生，外毒素A显然通过抑制蛋白质合成、直接细胞病变效应以及干扰宿主的细胞免疫功能而致病。针对外毒素A的抗体可保护机体免受实验性和临床性假单胞菌感染的某些生化、病理及致死后果。由外毒素A产生的类毒素目前正在进行评估，作为一种疫苗，可能用于人类预防假单胞菌病。
