Max Planck Institute for Polymer Research, 55128 Mainz, Germany.
Max Planck Institute for Chemistry, 55128 Mainz, Germany.
J Phys Chem B. 2020 Jun 18;124(24):4889-4895. doi: 10.1021/acs.jpcb.0c03001. Epub 2020 Jun 2.
Cold-adapted organisms use antifreeze proteins (AFPs) or ice-nucleating proteins (INPs) for the survival in freezing habitats. AFPs have been reported to be able to inhibit the activity of INPs, a property that would be of great physiological relevance. The generality of this effect is not understood, and for the few known examples of INP inhibition by AFPs, the molecular mechanisms remain unclear. Here, we report a comprehensive evaluation of the effects of five different AFPs on the activity of bacterial ice nucleators using a high-throughput ice nucleation assay. We find that bacterial INPs are inhibited by certain AFPs, while others show no effect. Thus, the ability to inhibit the activity of INPs is not an intrinsic property of AFPs, and the interactions of INPs and different AFPs proceed through protein-specific rather than universal molecular mechanisms.
适应寒冷的生物体使用抗冻蛋白（AFPs）或冰核蛋白（INPs）在冷冻栖息地中生存。据报道，AFPs 能够抑制 INPs 的活性，这种特性具有重要的生理相关性。但人们并不了解这种效应的普遍性，而且对于少数已知的 AFP 抑制 INP 的例子，其分子机制仍不清楚。在这里，我们使用高通量冰核测定法全面评估了五种不同 AFP 对细菌冰核活性的影响。我们发现某些 AFP 抑制细菌 INPs 的活性，而其他 AFP 则没有影响。因此，抑制 INPs 活性的能力不是 AFP 的固有特性，INPs 和不同 AFP 的相互作用是通过特定于蛋白质的而不是通用的分子机制进行的。
