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Our understanding of each of the biological sciences becomes heightened by the study of biochemistry and molecular biology. In the last few decades, advances in laboratory techniques for the study of these microscopic sciences have led us to a greater understanding of the central dogma of molecular biology – that DNA transcribes RNA which then gets translated into protein. Understanding protein synthesis is paramount in studying various medical fields, from the molecular basis of genetic diseases through antibiotic development to expressing recombinant proteins as drugs or clinical laboratory reagents. As one of the foundational concepts in biology, protein synthesis is sufficiently complex that many believe it evolved once, giving the protein synthetic machinery in all organisms on the planet a common ancestry.  Despite having certain underlying similarities in their mechanism, protein synthesis in the three major lines of descent (bacteria, archaea, and eukaryotes) has diverged to the point that substantive mechanistic differences have arisen.  These differences have been exploited in nature as organisms produce compounds targeting the protein synthetic machinery of competitors as they vie for limited resources. Science has modified many of these compounds that target the machinery for protein synthesis in pathogenic microbes for use in the clinic as antibiotics. As our understanding of the mechanisms of protein synthesis continues to grow, there will likely be countless additional applications for this knowledge in medicine, research, and industry.

Many human diseases result from changes in protein sequence caused by mutations that alter the correct readout of genetic information from gene to a functional protein. Defects in the protein synthetic machinery also cause a small but growing number of human diseases.  Examples of such pathologies follow. Sickle Cell Anemia Human hemoglobin contains two alpha and two beta chains to create a heterotetramer. In Sickle Cell Anemia, the sixth codon of the beta chain contains a missense mutation, in which glutamic acid, a charged amino acid, is replaced with valine, a neutral amino acid. This single amino acid difference affects the tertiary and quaternary structures of hemoglobin such that it distorts the biconcave shape of erythrocytes into sickle shapes in certain conditions.[9] Duchenne Muscular Dystrophy Like many X-linked diseases, DMD primarily affects males at an early age. It is characterized clinically by muscle weakness, calf pseudohypertrophy, and the Gower sign in a child. One of the pathophysiologic origins of this disease is the formation of a premature stop codon in an early exon of the dystrophin gene, which leads to a truncated dystrophin protein which compromises the integrity of the sarcomere and contractile function of the muscle.[10] Diamond-Blackfan Anemia While many human diseases result from mutations in the coding sequences of genes that affect protein production, Diamond-Blackfan anemia (DBA) is one of a growing number of conditions resulting from defects in the protein synthetic machinery. DBA is caused by autosomal dominant mutations in genes encoding proteins of either the 40S or 60S ribosomal subunit.  While the exact mechanisms underlying the pathophysiology of DBA are currently unknown, it seems likely that changes in cellular proteomes (the protein composition of a cell) resulting from suboptimal numbers of ribosomes contribute in part to the clinical features of the disease. These clinical features include a deficit in red blood cell production, small size, and a heterogeneous number of congenital anomalies.[11]