Atomic structures of ribosomes at work captured by in situ cryo-electron tomography

The ribosome is a highly conserved molecular machine respon-sible for protein biosynthesis in all living cells.The ribosomes of all species consist of two unequal subunits,and each of them has a specialized function,peptidyl-transfer for the large subunit(50S or 60S)and mRNA decoding for the small subunit(30S or 40S).