Diseases, Conditions, Syndromes

New drug target found for COVID-19

A new potential drug target has been identified in SARS CoV-2—the virus that causes COVID-19—by scientists at the Center of Structural Genomics of Infectious Diseases, or CSGID, who say multiple drugs will be needed to ...

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 ...

Diseases, Conditions, Syndromes

Antibody neutralizes SARS and COVID-19 coronaviruses

An antibody first identified in a blood sample from a patient who recovered from Severe Acute Respiratory Syndrome in 2003 inhibits related coronaviruses, including the cause of COVID-19.

Diabetes

Researchers identify trigger and mechanism in type 1 diabetes

Researchers at National Jewish Health have identified an elusive trigger of type 1 diabetes. A protein fragment formed in the pancreas activates the immune system's T cells, leading them to attack and destroy beta cells, ...

HIV & AIDS

New study finds HIV Achilles Heel

(Medical Xpress) -- A new study published in the Proceedings of the National Academy of Sciences shows how scientists have used a mathematical tool to possibly identify an Achilles heel in HIV which may lead to new vaccines ...

Oncology & Cancer

How the immune system becomes blind to cancer cells

T cells play a huge role in our immune system's fight against modified cells in the body that can develop into cancer. Phagocytes and B cells identify changes in these cells and activate the T cells, which then start a full-blown ...

Genetics

Reactivating aging stem cells in the brain

As people get older, their neural stem cells lose the ability to proliferate and produce new neurons, leading to a decline in memory function. Researchers at the University of Zurich have now discovered a mechanism linked ...

Alzheimer's disease & dementia

Scientists identify molecular trigger for Alzheimer's disease

Researchers have pinpointed a catalytic trigger for the onset of Alzheimer's disease – when the fundamental structure of a protein molecule changes to cause a chain reaction that leads to the death of neurons in the brain.

Medical research

Viral 'molecular scissor' is next COVID-19 drug target

American and Polish scientists, reporting Oct. 16 in the journal Science Advances, laid out a novel rationale for COVID-19 drug design—blocking a molecular "scissor" that the virus uses for virus production and to disable ...

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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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