Brophy P F, Knoop F C
Infect Immun. 1982 Jan;35(1):289-95. doi: 10.1128/iai.35.1.289-295.1982.
Antibiotic-associated enterocolitis was induced in guinea pigs by the intraperitoneal injection of clindamycin. The colonic and cecal mucosa and feces of acutely ill animals were cultured under aerobic and anaerobic conditions on 5% sheep blood agar plates and on a selective and differential medium for Clostridium difficile. All morphologically distinct colony types were isolated in pure culture and identified. A sterile cell-free filtrate of each isolate was tested for ability to induce morphological changes in cultured monolayers of mouse adrenal cells. The filtrate of a predominant isolate, Bacillus pumilus, induced an alteration of cellular morphology; the sterile filtrate of other isolates were unreactive. Toxin contained in cell-free filtrates of B. pumilus caused a syndrome identical to clindamycin-associated enterocolitis when injected intracecally into guinea pigs. The toxin had a molecular weight of 6,500 daltons as determined by molecular sieve chromatography and was inactivated with pronase, lipase, and trypsin. The minimal inhibitory concentrations of clindamycin and vancomycin for B. pumilus were 50 micrograms/ml and less than or equal to 0.4 micrograms/ml, respectively.
通过腹腔注射克林霉素在豚鼠中诱发抗生素相关性小肠结肠炎。对急性发病动物的结肠和盲肠黏膜以及粪便在需氧和厌氧条件下于5%绵羊血琼脂平板及艰难梭菌选择性鉴别培养基上进行培养。所有形态学上不同的菌落类型均在纯培养中分离并鉴定。对每个分离株的无菌无细胞滤液进行检测，以确定其诱导小鼠肾上腺细胞培养单层形态变化的能力。一株优势分离株短小芽孢杆菌的滤液诱导了细胞形态改变；其他分离株的无菌滤液无反应。短小芽孢杆菌无细胞滤液中所含毒素经盲肠内注射到豚鼠体内时，引发了与克林霉素相关性小肠结肠炎相同的综合征。通过分子筛色谱法测定，该毒素的分子量为6500道尔顿，且被链霉蛋白酶、脂肪酶和胰蛋白酶灭活。克林霉素和万古霉素对短小芽孢杆菌的最低抑菌浓度分别为50微克/毫升和小于或等于0.4微克/毫升。
