本文为了研究低剂量T-2和HT-2毒素经弯曲假单胞菌(Pseudomonas geniculata)生物转化至无游离态毒素检出时，降解产物是否具有遗传毒性。通过连续7 d给小鼠灌胃不同剂量T-2/HT-2毒素降解产物，检测小鼠骨髓嗜多染红细胞微核率和精子致畸率。结果表明雄性小鼠产生的微核率均高于雌性小鼠，各剂量组的微核率与阴性组相比差异显著(P<0.05)，10/20 ng/mL和25/50 ng/mL的雄性小鼠微核率与阳性组相比差异不显著(P＞0.05)。2.5/5 ng/mL T-2/HT-2组的小鼠精子畸形与阴性组相比差异不显著(P＞0.05)，畸形精子主要表现为胖头和折尾，随着T-2、HT-2剂量的增加，小鼠精子畸形率呈线性增加。说明经过弯曲假单胞菌(Pseudomonas geniculata)转化的T-2和HT-2毒素仍具有遗传毒性，而且雄性比雌性易感性更强，同时为T-2和HT-2毒素生物转化物中存在结合态的T-2毒素提供佐证。

The work was to determine whether low doses of degradation products of T-2 toxin and HT-2 toxin, after Pseudomonas geniculata biotransformation, showed genetic toxicity. The rates of micronucleated, polychromatic erythrocyte formation in bone marrow and sperm deformity, characterized by a swollen head and folded tail, were measured, 7 d after continual intragastric administration of T-2 and HT-2 toxin biotransformation products, at different doses, in mice. The results showed that the micronucleus formation rate in male mice was higher than that of the females, with significant differences (p < 0.05) between each dose-level and the negative control groups. Additionally, the micronucleus formation rate in male mice from the 10/20 and 25/50 ng/mL dose-level groups showed insignificant differences than that of the positive control group (p > 0.05). Sperm deformity rates in mice from the 2.5/5 ng/mL T-2/HT-2 dose group was significantly different (p < 0.05) than that of the negative group. As the dose of T-2/HT-2 toxin increased, the sperm deformity rate in mice increased linearly. Therefore, T-2 and HT-2 toxins were confirmed to still show genetic toxicity after biotransformation by Pseudomonas geniculate, and males were more susceptible than females. The study also provide evidence that there were binding forms of T-2 toxin in the biotransformation products of T-2 and HT-2.

国家自然科学基金资助项目(31171634；31371777)；“十二五”国家科技支撑计划项目之课题(2012BAD29B06)