Genetic Studies On Translational Accuracy Essay
The speed and accuracy of protein synthesis determines cell growth and fitness of cells. High accuracy is critical as misfolded protein can be detrimental and energetically costly to the cell. Too much accuracy at the cost of speed can also be detrimental to the growth of the organism. As decoding is the key to dictating the sequence of newly synthesized proteins (Alksne et al., 1993), the tRNA selection pathway during translation needs to maintain the balance between rate and accuracy (Zaher e Green, 2009); (Wohlgemuth et al., 2010; Wohlgemuth et al., 2011).
As efficient protein synthesis is essential to cell growth, translational accuracy is one of the important targets of antibiotics. Many antibiotics are directed against bacterial ribosomes and affect decoding and proofreading processes. Mutations within both the rRNA and r-proteins can render the antibiotics ineffective, making antibiotic resistance a predominant problem (Davies et al., 1998). Genetic, biochemical and structural analyses of antibiotic binding to the ribosome as well as ribosome that developed resistance has helped in identifying how different ribosomal components modulate fidelity.
Alterations of the components of the decoding center or the 30S subunit can affect the tRNA selection pathway and result in either error-prone (ram) mutants that lower accuracy or error-restrictive (hyperaccurate) mutants that increase accuracy. Recognition and binding of…