Enteroviruses are ubiquitous contaminants of surface waters, yet their fate in presence of microbial congeners is poorly understood. In this work, we investigated the inactivation of Echovirus-11 (E11) and Coxsackievirus-A9 (CVA9) by bacteria isolated from Lake Geneva. Incubation of E11 or CVA9 in biologically active lake water caused inactivation of 2- and 4-log₁₀, respectively, within 48 h. To evaluate the antiviral action of individual bacterial species, we isolated 136 bacterial strains belonging to 31 genera from Lake Geneva. The majority of isolates (92) induced decay of at least 1.5-log₁₀ of CVA9, whereas only 13 isolates induced a comparable inactivation on E11. The most extensive viral decay was induced by bacterial isolates producing matrix metalloproteases (MMPs). Correspondingly, the addition of a specific MMP inhibitor to lake water reduced the extent of inactivation for both viruses. A lesser, though significant protective effect was also observed with inhibitors of chymotrypsin-like or trypsin-like proteases, suggesting involvement of serine proteases in enterovirus inactivation in natural systems. Overall, we demonstrate the direct effect of bacterial proteases on the inactivation of enteroviruses and identify MMPs as effective controls on enteroviruses’ environmental persistence.

肠道病毒是地表水中普遍存在的污染物，但人们对它们在微生物同类物存在下的命运知之甚少。在这项工作中，我们研究了从日内瓦湖分离出的细菌对 Echovirus-11 (E11) 和 Coxsackievirus-A9 (CVA9) 的灭活作用。在具有生物活性的湖水中孵育 E11 或 CVA9 ，在 48 小时内分别导致 2-log 10 和 4-log _10失活。为了评估单个细菌物种的抗病毒作用，我们从日内瓦湖中分离出属于 31 个属的 136 株细菌。大多数分离物 (92) 引起至少 1.5-log _10的衰减CVA9，而只有 13 个分离株在 E11 上诱导了相当的失活。最广泛的病毒衰变是由产生基质金属蛋白酶 (MMP) 的细菌分离物引起的。相应地，向湖水中添加特定的 MMP 抑制剂可降低两种病毒的灭活程度。胰凝乳蛋白酶样或胰蛋白酶样蛋白酶的抑制剂也观察到较小但显着的保护作用，这表明丝氨酸蛋白酶参与了自然系统中肠道病毒的灭活。总的来说，我们证明了细菌蛋白酶对肠道病毒灭活的直接影响，并将 MMP 确定为对肠道病毒环境持久性的有效控制。