MINSTED tracking of single biomolecules

We show that MINSTED localization, a method whereby the position of a fluorophore is identified with precisely controlled beams of a STED microscope, tracks fluorophores and hence labeled biomolecules with nanometer/millisecond spatio-temporal precision. By updating the position for each detected photon, MINSTED recognizes fluorophore steps of 16 nm within < 250 microseconds using about 13 photons. The power of MINSTED tracking is demonstrated by quantifying side-steps of the motor protein kinesin-1 walking on microtubules and switching protofilaments.

本实验表明，MINSTED定位技术，一种通过精确控制STED显微镜的光束来识别荧光团位置的方法，能够以纳米/毫秒级的时空精度追踪荧光团及其所标记的生物大分子。通过更新每个检测到的光子的位置，MINSTED能够在小于250微秒的时间内识别出16纳米的荧光团步进，使用大约13个光子。MINSTED追踪技术的强大能力通过量化驱动蛋白kinesin-1在微管上的侧向移动和原纤维切换得到体现。