Ribosome detail render

The ribosome is a molecular complex responsible for protein synthesis, essential for cellular life.

About this subject

The ribosome is a cellular machinery composed of ribosomal RNA (rRNA) and proteins, organized into two subunits: large and small. It reads messenger RNA (mRNA) and translates the genetic code into amino acid chains, forming proteins. This process, called translation, occurs in the cytoplasm of prokaryotic and eukaryotic cells, or on the rough endoplasmic reticulum in eukaryotes.

Ribosomes were discovered in the 1950s by George Palade using electron microscopy, earning him the Nobel Prize in 1974. Since then, detailed studies have revealed their structural and functional complexity. Ribosomes are targets of many antibiotics, such as tetracyclines and macrolides, which inhibit bacterial protein synthesis without affecting human ribosomes due to structural differences.

Interestingly, ribosomes are not exclusive to cells; they are also found in mitochondria and chloroplasts, organelles of endosymbiotic origin. Translation speed can reach 20 amino acids per second in bacteria, while it is slower in eukaryotes. Advances in cryo-electron microscopy have allowed visualization of ribosomes at atomic resolution, revealing details of their dynamic function.

Frequently Asked Questions

What is the main function of the ribosome?

The ribosome is responsible for translating messenger RNA into proteins by linking amino acids in the sequence determined by the genetic code.

Are ribosomes found in all cell types?

Yes, all living organisms have ribosomes, from bacteria to human cells. They are also present in organelles such as mitochondria and chloroplasts.

Why do antibiotics like tetracycline target bacterial ribosomes?

These antibiotics bind to specific sites on bacterial ribosomes, inhibiting protein synthesis. Since human ribosomes have a different structure, the drug does not affect them, allowing treatment of infections.