Material Detail

Slideshow: Ramachandran Principle - Phi and Psi Angles in Proteins

Slideshow: Ramachandran Principle - Phi and Psi Angles in Proteins

A slideshow, at, with numerous animated molecular models explaining polypeptide backbones, peptide bonds, phi and psi angles with detailed illustrations of dihedral (torsion) angles. Inter-atomic clashes are shown forming and receding as phi and psi rotate, and relating clashes to the Ramachandran plot. There are links to a short practice quiz (immediate feedback), a Spanish translation of the slideshow, and a YouTube video version.



  • Editor Reviews
  • User Rating
  • Comments  (1) Comments
  • Learning Exercises
  • Bookmark Collections
  • Course ePortfolios
  • Accessibility Info

More about this material


Log in to participate in the discussions or sign up if you are not already a MERLOT member.
Eric Martz
Eric Martz (Faculty)
1 year ago
On October 9, 2018, Tania Araujo, a teacher at the School of Medicine at Benemérita Universidad Autónoma de Puebla in Puebla City, Mexico, wrote: Professor Martz: In this brief message I would like to thank you and your team for the online available slides about phi and psi angles in polypeptides, these are REALLY helpful. Greetings from Mexico! MSc. Tania Araujo