The lethal poison Ricin (best known as a weapon of bioterrorism), Diphtheria toxin (the causative agent of a highly contagious bacterial disease), and the widely used antibiotic tetracycline have one thing in common: They specifically target the cell's translational apparatus and disrupt protein synthesis. In this course, we will explore the mechanisms of action of toxins and antibiotics, their roles in everyday medicine, and the emergence and spread of drug resistance. We will also discuss the identification of new drug targets and how we can manipulate the protein synthesis machinery to provide powerful tools for protein engineering and potential new treatments for patients with devastating diseases, such as cystic fibrosis and muscular dystrophy. This course is one of many Advanced Undergraduate Seminars offered by the Biology Department at MIT. These seminars are tailored for students with an interest in using primary research literature to discuss and learn about current biological research in a highly interactive setting. Many instructors of the Advanced Undergraduate Seminars are postdoctoral scientists with a strong interest in teaching.

Biology is designed for multi-semester biology courses for science majors. It is grounded on an evolutionary basis and includes exciting features that highlight careers in the biological sciences and everyday applications of the concepts at hand. To meet the needs of today’s instructors and students, some content has been strategically condensed while maintaining the overall scope and coverage of traditional texts for this course. Instructors can customize the book, adapting it to the approach that works best in their classroom. Biology also includes an innovative art program that incorporates critical thinking and clicker questions to help students understand—and apply—key concepts.

By the end of this section, you will be able to:Explain the “central dogma” of protein synthesisDescribe the genetic code and how the nucleotide sequence prescribes the amino acid and the protein sequence

Since the discovery of the structure of the DNA double helix in 1953 by Watson and Crick, the information on detailed molecular structures of DNA and RNA, namely, the foundation of genetic material, has expanded rapidly. This discovery is the beginning of the "Big Bang" of molecular biology and biotechnology. In this seminar, students discuss, from a historical perspective and current developments, the importance of pursuing the detailed structural basis of genetic materials.

Students perform an activity similar to the childhood “telephone” game in which each communication step represents a biological process related to the passage of DNA from one cell to another. This game tangibly illustrates how DNA mutations can happen over several cell generations and the effects the mutations can have on the proteins that cells need to produce. Next, students use the results from the “telephone” game (normal, substitution, deletion or insertion) to test how the mutation affects the survivability of an organism in the wild. Through simple enactments, students act as “predators” and “eat” (remove) the organism from the environment, demonstrating natural selection based on mutation.

Students learn about mutations to both DNA and chromosomes, and uncontrolled changes to the genetic code. They are introduced to small-scale mutations (substitutions, deletions and insertions) and large-scale mutations (deletion duplications, inversions, insertions, translocations and nondisjunctions). The effects of different mutations are studied as well as environmental factors that may increase the likelihood of mutations. A PowerPoint® presentation and pre/post-assessments are provided.