Gonzalez E A, Blanco J
Zentralbl Bakteriol Mikrobiol Hyg A. 1985 Aug;260(1):1-7. doi: 10.1016/s0176-6724(85)80092-4.
We have investigated the enterotoxic activity of culture filtrates and their methanol extracted fractions from 10 ST (STa or STb) producing Escherichia coli strains from human, porcine and bovine origin, in the infant mouse test (IMT) as well as in the rabbit intestinal loop test (RILT). Unconcentrated culture filtrates and methanol-soluble fractions from the eight STa-producing strains were positive in the IMT while methanol-insoluble fractions obtained from these STa-positive strains, like methanol-soluble and -insoluble fractions from the two strains producing only STb, lacked activity in the IMT. Unconcentrated culture filtrates from all ST-producing strains were unable to cause fluid accumulation in the rabbit ligated intestinal loops after 6 h incubation. When this material, concentrated 5-fold, was tested again, the culture filtrates and methanol-soluble fractions from all STa-producing strains yielded strongly positive fluid accumulation in the RILT, whereas culture filtrates and their methanol extracted fractions from the strains producing only STb, like methanol-insoluble fractions from four STa-producing strains, caused slight fluid secretion in the rabbit intestinal loops.
我们在幼鼠试验（IMT）以及兔肠袢试验（RILT）中，研究了来自人源、猪源和牛源的10株产ST（STa或STb）大肠杆菌菌株的培养滤液及其甲醇提取物的肠毒素活性。8株产STa菌株的未浓缩培养滤液和甲醇可溶部分在IMT中呈阳性，而从这些产STa阳性菌株获得的甲醇不溶部分，以及仅产STb的2株菌株的甲醇可溶和不溶部分，在IMT中均无活性。所有产ST菌株的未浓缩培养滤液在6小时孵育后均不能使兔结扎肠袢出现液体蓄积。当对浓缩5倍的该物质再次进行测试时，所有产STa菌株的培养滤液和甲醇可溶部分在RILT中产生强烈阳性的液体蓄积，而仅产STb菌株的培养滤液及其甲醇提取物，以及4株产STa菌株的甲醇不溶部分，在兔肠袢中引起轻微的液体分泌。
