McCardell B A, Madden J M, Kothary M H, Sathyamoorthy V
Division of Virulence Assessment, Food and Drug Administration, Washington, DC 20204, USA.
Microb Pathog. 1995 Jul;19(1):1-9. doi: 10.1006/mpat.1995.0039.
A Chinese hamster ovary (CHO) cell-elongating toxin produced by Aeromonas hydrophila was purified from cell-free supernatant fluids by ammonium sulfate precipitation and fast protein liquid chromatography. The purified toxin had an isolelectric point (pl) of 3.7 and a molecular weight of 70,000 in a single band on isoelectric focusing (IEF) gels and SDS-PAGE gels, respectively. The N-terminal sequence, amino acids 1-20, and the amino acid content were determined from Western blots of the 70 kDa band. No homology with any known microbial toxin was found. CHO cell activity was not neutralized by antiserum to cholera toxin (anti-CT), and the toxin did not react with anti-CT on Western blots. The toxin did not increase cyclic AMP, cyclic GMP, or prostaglandin E2 levels in CHO cells. No cytotoxic activity was observed. Intragastric administration of purified toxin (5 x 10(4) and 5 x 10(8) CHO cell units) induced intestinal fluid accumulation in infant mice. These results suggest that this toxin may be a novel cytotonic toxin distinct from previously described toxins produced by A. hydrophila or A. sobria.
通过硫酸铵沉淀和快速蛋白质液相色谱法，从嗜水气单胞菌产生的中国仓鼠卵巢（CHO）细胞伸长毒素的无细胞上清液中进行纯化。纯化后的毒素在等电聚焦（IEF）凝胶和SDS-PAGE凝胶上的等电点（pl）分别为3.7，分子量为70,000，在单一条带上。通过对70 kDa条带进行蛋白质免疫印迹法确定了N端序列（氨基酸1-20）和氨基酸含量。未发现与任何已知微生物毒素具有同源性。霍乱毒素抗血清（抗CT）不能中和CHO细胞活性，并且该毒素在蛋白质免疫印迹上不与抗CT发生反应。该毒素不会增加CHO细胞中环状AMP、环状GMP或前列腺素E2的水平。未观察到细胞毒性活性。给幼鼠灌胃纯化毒素（5×10⁴和5×10⁸个CHO细胞单位）会导致肠道液体蓄积。这些结果表明，这种毒素可能是一种新型的细胞张力毒素，不同于先前描述的嗜水气单胞菌或温和气单胞菌产生的毒素。
