Question

The very first step which ensures the accuracy in the translation process is

Answer 1

The very steps which ensures accuracy in translation process are:

1. The aminoacyl-tRNA synthatase enzyme provides accuracy in attaching an accurate amino acid with a tRNA containing the anticodon for it. This happens in two steps

a) 1st the correct amino acid enters the active site which has the proper dimention for it. This excludes all other incorrect amino acids. But sometimes amino acid wih similar dimentions (isoleucine in place of valine) may enter, so the next step

b) After attachment of the amino acid with one active site of the enzyme , the tRNA comes and binds with the enzyme which forces the amino acid to shift into anither active site. This shifting requires specific minute accuracy in dimention. At this point all the incorrect amino acids gets out of the enzyme system.

2. The attachment of charged tRNA to ribosomal A site is activated by Elongation factor EF-Tu. When a tRNA anticodon correctly recognises the mRNA codon the GTP bound to EF-Tu undergoes hydrolysis and forms GDP and the EF-Tu detaches from the A-site making way for tRNA attachment. The GTP hydrolysis doesnt take place if the codon-anticodon pairing is not correct thus do not let an incorrect tRNA to bind to the A site.