Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada.
Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada.
PLoS Biol. 2022 Sep 6;20(9):e3001772. doi: 10.1371/journal.pbio.3001772. eCollection 2022 Sep.
Potassium ion (K+) plays a critical role as an essential electrolyte in all biological systems. Genetically-encoded fluorescent K+ biosensors are promising tools to further improve our understanding of K+-dependent processes under normal and pathological conditions. Here, we report the crystal structure of a previously reported genetically-encoded fluorescent K+ biosensor, GINKO1, in the K+-bound state. Using structure-guided optimization and directed evolution, we have engineered an improved K+ biosensor, designated GINKO2, with higher sensitivity and specificity. We have demonstrated the utility of GINKO2 for in vivo detection and imaging of K+ dynamics in multiple model organisms, including bacteria, plants, and mice.
钾离子（K+）在所有生物系统中作为必需的电解质起着至关重要的作用。遗传编码的荧光 K+生物传感器是进一步了解正常和病理条件下依赖于 K+的过程的有前途的工具。在这里，我们报告了先前报道的遗传编码荧光 K+生物传感器 GINKO1 在 K+结合状态下的晶体结构。通过结构引导优化和定向进化，我们设计了一种改良的 K+生物传感器，命名为 GINKO2，具有更高的灵敏度和特异性。我们已经证明了 GINKO2 在包括细菌、植物和小鼠在内的多种模式生物中用于体内检测和成像 K+动力学的实用性。
