ACTIVATION OF THE HOLE-FORMING TOXIN AEROLYSIN BY EXTRACELLULAR PROCESSING
ACTIVATION OF THE HOLE-FORMING TOXIN AEROLYSIN BY EXTRACELLULAR PROCESSING
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DOI：
10.1128/jb.163.1.336-340.1985
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发表时间：
1985-01-01
影响因子：
3.2
通讯作者：
BUCKLEY, JT
中科院分区：
文献类型：
--
作者：
HOWARD, SP;BUCKLEY, JT
在嗜水气单胞菌培养上清中观察到气溶素与一种分子量较高的蛋白质之间的亲核-产物关系。通过硫酸铵沉淀、离子交换和羟基磷灰石层析分离出较大的蛋白质，并与纯化的气溶素进行比较。它的溶血性至少比气溶素低250倍。两种蛋白质在氨基末端具有相同的氨基酸序列。从2个获得的溴化氰片段是相同的，除了每个蛋白质含有1个独特的片段，并且来自较大蛋白质的片段比从气溶素获得的片段大2500道尔顿。用胰蛋白酶或用胞外气单胞菌蛋白酶处理导致较大蛋白质快速转化为MW和活性对应于气溶素的形式。结果表明气溶素作为原毒素输出到培养物上清液中，该原毒素随后通过从C末端蛋白水解去除肽而被激活。
A precursor-product relationship between aerolysin and a protein with a higher MW was observed in culture supernatants of Aeromonas hydrophila. The larger protein was isolated by ammonium sulfate precipitation and ion-exchange and hydroxyapatite chromatography and compared with purified aerolysin. It was at least 250 times less hemolytic than aerolysin. Both proteins had the same amino acid sequence at the amino terminus. Cyanogen bromide fragments obtained from the 2 were identical except that each protein contained 1 unique fragment, and the fragment from the larger protein was 2500 daltons larger than the fragment obtained from aerolysin. Treatment with trypsin or with an extracellular Aeromonas protease resulted in rapid conversion of the larger protein to a form corresponding in MW and activity to aerolysin. The results indicate that aerolysin is exported to the culture supernatant as a protoxin which is later activated by proteolytic removal of a peptide from the C terminus.