You might not even know this scientific analysis, but it is so good that a newer one has not changed its state from invaluable. Learn more about the dinosaur technology right here.
In most scientific fields, technologies have a shorter and shorter lifetime and newer approaches quickly surpass older ones. This makes new scientific discoveries more likely, since research can be made rapidly and efficiently. However, especially one technology keeps surviving and is not replaced by a newer one. It is simply too good to phase out.
The dinosaur’s name: Edman degradation
Even though it was announced for the first time in 1950, N-terminal Edman degradation/sequencing (or just Edman degradation) is still widely used today. University researchers and biotech companies use it to find out which amino acids a small protein (peptide) consists of.
Even though it needs expensive chemicals and spare parts that are barely being produced any more, it gives the user a few (important) advantages compared to newer methods. One of the newer methods is mass spectrometry, which is often applied to analyze the amino acid content in complex samples with many different molecules at once. However, let’s talk more about amino acids and the advantages of the ‘dinosaur’.
What is an N-terminal? (no, not the one at the airport)
To explain how the technique works, we must first go over the structure of an amino acid sequence, which is the foundation for a protein’s final structure.
The first part of the amino acid sequence is termed the N-terminal, as it refers to the amino group -NH2 located at the end of the protein. It often determines the protein’s precise location in cells and thus also influences the protein’s overall function. Moreover, the first amino acid in the N-terminal is crucial for the protein to survive degradation by maintenance systems in the body.
It is of interest to investigate the structure of the N-terminal during production of biopharmaceutical medicine, with peptides (small proteins) as the active substance. Therefore, the Edman degradation method is used to investigate the structure, when medicine with peptides is produced.
And there is a clear reason why another method has not replaced this old dinosaur method.
Why it’s not extinct
Since the peptides in medicinal products often determine the effectiveness of the treatment, it is thoroughly analyzed and monitored during the development and production of medicine.
Newer methods like Top-Down sequencing and de-novo sequencing exists and are used to sequence peptides. However, the main advantage of the old Edman degradation is the method’s careful treatment of the peptide. It simply cuts a single amino acid off the N-terminal sequence at a time. Thereby, it does not affect the rest of the peptide in the process and the rest of the peptide does not affect the analysis. After the N-terminal of the peptide has been analyzed, it is compared to the expected sequence. This comparison is a then a direct measure of the production process’ efficacy.