Energy & Green Tech

Green adhesives made from whey

Every day, large quantities of whey are produced as a byproduct by the dairy industry. In Germany alone, this amounts to 12.6 million tons a year. For each kilogram of cheese, for example, 9 kilograms of whey are produced. ...

Engineering

Fancy a side of 3D printed carrots and crickets with your meal?

As the global population continues to age and grow, the demand for protein-rich food is also expected to increase concurrently. This has also caused concerns on increasing greenhouse gases, land and water consumption associated ...

Engineering

Automation speeds the search for stable proteins

Harnessing the power of robotics and machine intelligence, researchers from Princeton Engineering and Rutgers University have found a way to design stable proteins in a fraction of the time of current state of the art. The ...

Computer Sciences

Computer science expert discusses computing power and innovation

Moore's Law is the famous prognostication by Intel co-founder Gordon Moore that the number of transistors on a microchip would double every year or two. This prediction has mostly been met or exceeded since the 1970s—computing ...

Computer Sciences

Using AI to analyze large amounts of biological data

Researchers at the University of Missouri are applying a form of artificial intelligence (AI)—previously used to analyze how National Basketball Association (NBA) players move their bodies—to now help scientists develop ...

Computer Sciences

AI helps with drug discovery

Drug-target interaction is a prominent research area in drug discovery, which refers to the recognition of interactions between chemical compounds and the protein targets. Chemists estimate that 1060 compounds with drug-like ...

Machine learning & AI

Deep learning reveals how proteins interact

Scientist are now combining recent advances in evolutionary analysis and deep learning to build three-dimensional models of how most proteins in eukaryotes interact. (Eukaryotes are organisms whose cells have a membrane-bound ...

Computer Sciences

Identifying individual proteins using nanopores and supercomputers

The amount and types of proteins our cells produce tell us important details about our health and how our bodies work. But the methods we have of identifying and quantifying individual proteins are inadequate to the task. ...

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Protein

Proteins (also known as polypeptides) are organic compounds made of amino acids arranged in a linear chain. The amino acids in a polymer chain are joined together by the peptide bonds between the carboxyl and amino groups of adjacent amino acid residues. The sequence of amino acids in a protein is defined by the sequence of a gene, which is encoded in the genetic code. In general, the genetic code specifies 20 standard amino acids, however in certain organisms the genetic code can include selenocysteine — and in certain archaea — pyrrolysine. Shortly after or even during synthesis, the residues in a protein are often chemically modified by post-translational modification, which alter the physical and chemical properties, folding, stability, activity, and ultimately, the function of the proteins. Proteins can also work together to achieve a particular function, and they often associate to form stable complexes.

Like other biological macromolecules such as polysaccharides and nucleic acids, proteins are essential parts of organisms and participate in virtually every process within cells. Many proteins are enzymes that catalyze biochemical reactions and are vital to metabolism. Proteins also have structural or mechanical functions, such as actin and myosin in muscle and the proteins in the cytoskeleton, which form a system of scaffolding that maintains cell shape. Other proteins are important in cell signaling, immune responses, cell adhesion, and the cell cycle. Proteins are also necessary in animals' diets, since animals cannot synthesize all the amino acids they need and must obtain essential amino acids from food. Through the process of digestion, animals break down ingested protein into free amino acids that are then used in metabolism.

Proteins were first described and named by the Swedish chemist Jöns Jakob Berzelius in 1838. However, the central role of proteins in living organisms was not fully appreciated until 1926, when James B. Sumner showed that the enzyme urease was a protein. The first protein to be sequenced was insulin, by Frederick Sanger, who won the Nobel Prize for this achievement in 1958. The first protein structures to be solved were hemoglobin and myoglobin, by Max Perutz and Sir John Cowdery Kendrew, respectively, in 1958. The three-dimensional structures of both proteins were first determined by x-ray diffraction analysis; Perutz and Kendrew shared the 1962 Nobel Prize in Chemistry for these discoveries. Proteins may be purified from other cellular components using a variety of techniques such as ultracentrifugation, precipitation, electrophoresis, and chromatography; the advent of genetic engineering has made possible a number of methods to facilitate purification. Methods commonly used to study protein structure and function include immunohistochemistry, site-directed mutagenesis, and mass spectrometry.

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