Lecture Notes: Bacterial Ribosomes

Introduction

• Presenter: Dr. O
• Topic: Bacterial ribosomes and interesting related concepts.

Prokaryotic Ribosomes

• Composed of:
  • Large subunit: 50-S
  • Small subunit: 30-S
• Total ribosome: 70-S (Note: Svedberg Units are not additive)
• Eukaryotic ribosomes: 80-S

Organelle Ribosomes

• Mitochondria and chloroplasts:
  • Contain 70-S ribosomes, similar to bacteria.
• Endosymbiotic Theory:
  • Suggests eukaryotic cells evolved from smaller symbiotic cells.
  • Mitochondria and chloroplasts may have been independent organisms.

Antibiotics and Human Impact

• Antibiotics target 70-S ribosomes to kill bacteria.
• Possible effects on human mitochondria:
  • Some argue mitochondrial membranes block antibiotics.
  • Others, like Dr. O, suggest mitochondria may be affected, especially in athletes.
  • Elite athletes may experience more significant effects due to high mitochondrial use.

Bacterial Protein Synthesis

• Advantage of bacteria: Speed of protein synthesis.
• Lack of nucleus:
  • Allows simultaneous transcription and translation.
  • RNA polymerase transcribes DNA into RNA while ribosomes begin translation.
• Results in rapid protein and DNA production:
  • Short bacterial generation times, e.g., 20 minutes.

Conclusion

• Speed is a key advantage for bacterial growth and reproduction.
• Future discussions will cover antibiotics and ribosomal interference.

"Have a wonderful day. Be blessed." - Dr. O