Proofreading and Protein Fidelity

Cells get two chances, not just one, to fix their mistakes is a Biology News item about a cellular proofreading function which helps ensure a high degree of fidelity in protein synthesis. Mistakes in the synthesis process are rare and it is believed that about one error for every 10,000 linked amino acids occurs.

A key enzyme involved in proofreading is known as Phenylalanyl-tRNA synthetase (PheRS); an enzyme having an important role to play in maintaining cellular quality control. Its specific function entails correct amino acid selection allowing for proper sequencing of amino acid polymers within a protein. The relevant amino acid is phenylalanine.

Michael Ibba is the senior author of the discussed study whose research results were published in the journal Molecular Cell. Ibba is an associate professor of microbiology at Ohio State University. The research revealed that prior to protein formation a check on the amino acid polymers is made. The enzyme PheRS is able to correct a mistake resulting from its own activity. PheRS has two catalytic domains.

Disrupting the function of enzymes involved in proofreading can be a valued function of antibiotics. E. coli was used in the experiments.