aminoacyltRNAsyntetaaseja

AminoacyltRNA synthetases, often abbreviated as aaRS, are a crucial class of enzymes found in all living organisms. Their primary function is to catalyze the aminoacylation of transfer RNA (tRNA) molecules. This process, also known as tRNA charging, is essential for protein synthesis. Each aminoacyltRNA synthetase is specific for a particular amino acid and its corresponding tRNA(s). The enzyme attaches the correct amino acid to the 3' end of its cognate tRNA molecule, forming an aminoacyl-tRNA. This charged tRNA then carries the amino acid to the ribosome, where it is incorporated into the growing polypeptide chain according to the mRNA sequence.

The reaction catalyzed by aminoacyltRNA synthetases occurs in two steps. First, the enzyme activates the amino acid by forming an aminoacyl-adenylate intermediate, utilizing ATP. In the second step, the activated amino acid is transferred to the acceptor stem of the appropriate tRNA molecule, releasing AMP. This high degree of specificity ensures the fidelity of the genetic code, as errors in aminoacylation would lead to the incorporation of incorrect amino acids into proteins, potentially resulting in non-functional or harmful proteins. Mutations in genes encoding aminoacyltRNA synthetases can lead to various human diseases, highlighting their critical role in cellular function and health.