Proteins are major building blocks of life. The protein content of a cell and an organism provides key information for the understanding of biological processes and disease. Despite the importance of protein analysis, only a handful of techniques are available to determine protein sequences, and these methods face limitations, for example, requiring a sizable amount of sample. Single-molecule techniques would revolutionize proteomics research, providing ultimate sensitivity for the detection of low-abundance proteins and the realization of single-cell proteomics. In recent years, novel single-molecule protein sequencing schemes that use fluorescence, tunnelling currents and nanopores have been proposed. Here, we present a review of these approaches, together with the first experimental efforts towards their realization. We discuss their advantages and drawbacks, and present our perspective on the development of single-molecule protein sequencing techniques.

蛋白质是生命的主要组成部分。细胞和生物体的蛋白质含量为理解生物学过程和疾病提供了关键信息。尽管蛋白质分析很重要，但只有少数技术可用于确定蛋白质序列，并且这些方法面临着局限性，例如，需要大量的样品。单分子技术将彻底改变蛋白质组学的研究，为检测低丰度蛋白质和实现单细胞蛋白质组学提供极高的灵敏度。近年来，已经提出了使用荧光，隧道电流和纳米孔的新型单分子蛋白质测序方案。在这里，我们对这些方法进行了综述，并为实现这些方法进行了首次实验。