Amino acids are small organic molecules that make up peptides and proteins. All living organisms share the same set of amino acids. Amino acids come together in different orders (sequences) to form proteins. As such, each type of protein has a different three-dimensional structure and biological activity.
The transition from polyclonal antibody drugs to a more targeted monoclonal approach was made possible through a series of scientific and technological advancements; the most notable of which is the hybridoma technique developed by Köhler and Milstein, which allowed the generation of pure antibodies at scale.
Protein sequencing is a method that typically utilizes mass spectrometry (MS) to determine the amino acid code of a protein1. Prior to the development of mass spectrometry, Edman degradation, a method involving the stepwise degradation of peptides to derive the order of amino acids, was the mainstream approach. Nowadays, mass spectrometry is favored due to its ease of use and high throughput capabilities, though Edman degradation is still employed for specific applications in which the technique is well suited.
Monoclonal antibodies (mAbs) are homogenous antibodies that bind to a single epitope on an antigen. Kohler and Milstein generated the first mAbs when they developed hybridoma technology in the 1970s. Because of the specificity, homogeneity and unlimited availability, mAbs are valuable reagents used in a variety of important applications including treatment and diagnosis of diseases
Amino acids (aa)—the building blocks of proteins—are simple molecules characterized by a variable R group flanked either side by an amino group and a carboxyl group. With around 20 different commonly found amino acids, each one can bond with another to produce chains that can be classified as peptides (typically below 50 aa) and proteins (sequences above 50 aa)—molecules ubiquitous to every known organism.
Amino acid sequencing is commonly performed using Edman degradation or mass spectrometry (MS). While mass spectrometry is favoured for its high throughput capabilities and ease of use, both techniques possess their own features and limitations. This article summarizes some of the key pain points inherent in the two methodologies when determining the amino acid sequence.
Antibodies are used in a variety of ways in academia and industry, from tools to therapeutics. Because antibodies are produced using live processes, which are naturally error-prone, validation is required from time to time. Furthermore, to develop biological therapeutics, the protein sequence must be confirmed as part of the regulatory process.
Written by Yuning Wang, PhD August 1, 2021 What is DNA Sequencing? DNA sequencing is the process of determining the precise order of four nucleotides bases—adenine (A), guanine (G), cytosine (C), and thymine (T)—that make up the DNA molecule. From Sanger sequencing to next-generation sequencing (NGS), DNA sequencing’s accessibility and ease [...]
Written by María Gerpe, PhD July 23, 2021 Why the Amino Acid Sequence Matters As proteins are assembled, they fold into different structural orders: from primary to quaternary. The exact sequence of the primary structure (the amino acid sequence) will dictate how a protein will fold and therefore function. The importance [...]
Proteins are composed of peptide chains, which in turn are made up of a string or linear sequence of amino acids (Figure 1A). Every amino acid has a basic structure containing an amino (-NH2) group and a carboxylic (-COOH) group (Figure 1B). To form a peptide, amino acids link to each other via a peptide bond, which involves the reaction between the carboxylic group of one amino acid and the amine group of another amino acid (Figure 1B). As such, the primary structure of a protein is typically recorded starting at the amino-terminal (N) end and continuing to the carboxyl-terminal (C) end. The primary protein structure may be directly sequenced from a sample of the protein itself or inferred from the DNA sequence.