Parkinson's & Movement disorders

Building momentum against Parkinson's

A team led by researchers at Brigham and Women's Hospital and Harvard Medical School has taken a step toward solving a central mystery of Parkinson's disease: What is the normal function of the protein whose misfolding causes ...

Medications

New therapeutic option for head and neck carcinomas

The various manifestations of head and neck carcinomas rank sixth in frequency worldwide and are fatal for about half a million people every year. In a quarter of cases, head and neck squamous cell carcinoma (HNSCC) is caused ...

Diseases, Conditions, Syndromes

New web server helps identify COVID-19 drug candidates

Rice University researchers have introduced an online portal to help researchers screen COVID-19 drug candidates that might attack specific proteins of the SARS-CoV-2 virus.

Oncology & Cancer

A leap forward in research on CAR T cell therapy

In cancer immunotherapy, cells in the patient's own immune system are activated to attack cancer cells. CAR T cell therapy has been one of the most significant recent advances in immunotherapies targeted at cancer.

page 1 from 13

Carrier protein

Carrier proteins are proteins that transport a specific substance or group of substances through intracellular compartments or in extracellular fluids (e.g. in the blood) or else across the cell membrane. Some of the carriers are water-soluble proteins that may or may not interact with biological membranes, such as some transporters of small hydrophobic molecules, whereas others are integral transmembrane proteins.

Carrier proteins transport substances out of or into the cell by facilitated diffusion and active transport. Each carrier protein is designed to recognize only one substance or one group of very similar substances. The molecule or ion to be transported (the substrate) must first bind at a binding site at the carrier molecule, with a certain binding affinity. Following binding, and while the binding site is facing, say, outwards, the carrier will capture or occlude (take in and retain) the substrate within its molecular structure and cause an internal translocation, so that it now faces the other side of the membrane. The substrate is finally released at that site, according to its binding affinity there. All steps are reversible.

For example:

This text uses material from Wikipedia, licensed under CC BY-SA