Neuroscience

A new hope in treating neurodegenerative disease

A research team led by Professor Sung Bae Lee of Brain and Cognitive Sciences and Professor Daehee Hwang of New Biology (vice-head of the Plant Age and Life Research Group, IBS) has identified the early neuropathological ...

Psychology & Psychiatry

Synaptic protein regulates anxiety behaviour

Anxiety disorders are severe mental disorders in which patients suffer from intense fears and anxiety or from sudden, inexplicable panic attacks. In extreme cases, the affected individuals barely leave their homes, which ...

Genetics

Stray proteins cause genetic disorders

The seizures typically begin in the first months of life. It often takes years, however, before those suffering from the rare glucose transporter type 1 (Glut1) deficiency syndrome obtain a correct diagnosis. If the disorder ...

Parkinson's & Movement disorders

Study raises doubts on a previous theory of Parkinson's disease

Parkinson's disease was first described by a British doctor more than 200 years ago. The exact causes of this neurodegenerative disease are still unknown. In a study recently published in eLife, a team of researchers led ...

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Protein structure

Proteins are an important class of biological macromolecules present in all biological organisms, made up of such elements as carbon, hydrogen, nitrogen, oxygen, and sulphur. All proteins are polymers of amino acids. The polymers, also known as polypeptides, consist of a sequence of 20 different L-α-amino acids, also referred to as residues. For chains under 40 residues the term peptide is frequently used instead of protein. To be able to perform their biological function, proteins fold into one, or more, specific spatial conformations, driven by a number of noncovalent interactions such as hydrogen bonding, ionic interactions, Van Der Waals forces and hydrophobic packing. In order to understand the functions of proteins at a molecular level, it is often necessary to determine the three dimensional structure of proteins. This is the topic of the scientific field of structural biology, that employs techniques such as X-ray crystallography or NMR spectroscopy, to determine the structure of proteins.

A number of residues are necessary to perform a particular biochemical function, and around 40-50 residues appears to be the lower limit for a functional domain size. Protein sizes range from this lower limit to several thousand residues in multi-functional or structural proteins. However, the current estimate for the average protein length is around 300 residues. Very large aggregates can be formed from protein subunits, for example many thousand actin molecules assemble into a microfilament.

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