Synthase binds ATP and the appropriate aa to form aminoacyl-adenylate (release pyrophosphate Ppi)
The newly formed complex binds to the corresponding tRNA molecule, and the aa is transferred from the aa-AMP to 3’ OH of tRNA
-some mediate a proofreading reaction also… if the tRNA is found to be improperly charged, the aminoacyl-tRNA bond is hydrolyzed
Each codon requires a tRNA molecule with a complemetary anticodon. There are 61 available mRNA codons but only 45 species of tRNA (usually). Wobble Base Pairs hypothesizes that the 5’ base on the anticodon (which binds to the 3’ base on the mRNA) is not as spatially confined as the other two bases and thus could have non-standard base pairing.
stability is comprable to a normal base pair
Eukaryotic ribosomes are either free in the cytoplasm or attached to the outer membrane of the endoplasmic reticulum
In prokaryotes (bacteria) the ribosomes are only free forms in the cytoplams.
Eukaryotic ribosomes are much larger then prokaryotic ribosomes.
(while euk has transcription in nucleus and translation in cytosol, prok have both in cytosol, no nucleus)