Frederick Sanger won the Nobel Prize in Chemistry in 1958 for determining the amino acid sequence of insulin. This was a groundbreaking achievement in the field of biochemistry, as it was the first time that the complete structure of a protein had been deciphered.

Here's why his work was so important:

* Understanding protein structure: Knowing the exact sequence of amino acids in a protein allowed scientists to understand its three-dimensional shape and how it functions. This opened up a whole new area of research into protein structure and function.

* Implications for medicine: Insulin is a vital hormone involved in regulating blood sugar levels. Sanger's work helped researchers understand how insulin works at a molecular level, which paved the way for the development of treatments for diabetes.

* Methodological advancements: The techniques Sanger developed to sequence insulin, like the use of chromatography and electrophoresis, became fundamental tools in molecular biology and continue to be used today.

Sanger's work revolutionized our understanding of proteins and their role in biological processes, making him a true pioneer in the field of biochemistry. His achievements earned him another Nobel Prize in Chemistry in 1980 for his work on DNA sequencing, further solidifying his status as one of the most important scientists of the 20th century.