Wide industrial, environmental and biomedical applications of carbon nanotubes (CNTs) are allowing them to enter the environment. Their toxicity to microorganisms has been experimentally reported, but the underlying molecular mechanism is still unclear. Here, we investigated the conformational transitions in widely distributed microbial enzymes in the presence and absence of single-walled carbon nanotubes (SWCNTs) by molecular dynamics (MD) simulations. Our study identifies a new mechanism by which SWCNTs produce possible toxicity to microbes by inducing significant changes in enzymatic conformations. The protein–protein interactions undergo significant transitions in two monomers, either towards or away from each other in the presence of SWCNTs. The significant conformational changes in microbial enzymes may inactivate the microbial enzymes and disturb the microbial metabolism.

中文翻译：

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碳纳米管与微生物酶的相互作用：构象转变和潜在毒性

碳纳米管（CNT）在工业，环境和生物医学领域的广泛应用使它们能够进入环境。它们对微生物的毒性已有实验报道，但其潜在的分子机制仍不清楚。在这里，我们通过分子动力学（MD）模拟研究了在存在和不存在单壁碳纳米管（SWCNTs）的情况下，广泛分布的微生物酶中的构象转变。我们的研究确定了一种新的机制，SWCNTs通过诱导酶构象的显着变化而对微生物产生可能的毒性。在存在SWCNT的情况下，两种蛋白质之间的蛋白质-蛋白质相互作用会发生明显的过渡，彼此接近或彼此远离。