Save lonely Molecules: A new antioxidant system
Scientists at the University of Michigan, together with their Belgian colleagues, have discovered a new system for protecting single cysteine molecules from the action of free radicals. The results of their work are published in the journal Science on November 20.
Most readers have probably heard about the scientific evidence of how important a permanent life partner is for health. The same phenomena are true at the molecular level: for example, single molecules of the amino acid cysteine are more vulnerable to various kinds of damage, unlike molecules that have a "pair".
Numerous protein molecules of our body are built from amino acids and perform the most important functions, but their integrity can be violated by active forms of oxygen and other oxidizing agents. Over time, damage to protein molecules accumulates and can lead to cancer, heart disease, Alzheimer's disease or other equally serious disorders. To resist harmful processes, cells produce special proteins that repair damage or suppress oxidative stress. However, until now, no such system has been known for single cysteine molecules, especially susceptible to damage.
In the course of the study, Kate Carroll and colleagues from the University of Michigan used previously developed chemical probes to study and confirm the mechanism involved in the protection process.
The results obtained by the researchers showed that a protein called DsbG, located in the periplasmic space of bacteria, performs such an important function, protecting single amino acid residues of cysteine from hyperoxidation and inactivation. The periplasmic space is a division between the inner and outer cell membranes of bacteria, such as Escherichia coli, used in the work. Although there is no periplasmic space in human cells, they have a similar membrane network known as the endoplasmic reticulum.
Given that proteins from the DsbG family are widely distributed, and the genes encoding them have been identified in most genomes, including the human one, some of their representatives may play a similar role in regulating cysteine oxidation. Understanding these biological processes can contribute to the improvement of antioxidant therapy methods.
Eternal Youth Portal www.vechnayamolodost.ru based on the materials of the University of Michigan: Saving the single cysteine: new antioxidant system found23.11.2009