Amino Acids
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Learn to draw and name 3D alpha-amino carboxylic acids on paper!
(Available through the Livescribe app store.)

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This application can recognize 20 2D and 43 3D amino acids!

The highlighted text is the pen's display.

Once you have entered Amino Acids, you can select one of three options from the vertical navigation menu:

Option What you can do?
Tutorial Mode: See the name of your drawing.
Quiz Mode: Draw a given amino acid.
Instructions Website: Remember where to find instructions.

Tutorial Mode:  Draw the following structure lifting up the pen between drawing each line or atomic symbol.  Make sure the lines are straight and longer than the separation of lines on college rule paper.  Draw an atomic symbol after you draw a line that represents one of its bonds.  As you draw you may see the molecular formula, e.g., CH2O2, or the name of the amino acid that you have drawn, i.e., proline.  You can start a new drawing by reentering the Tutorial Mode:, by double tapping twice on the paper or by navigating right.

Quiz Mode:  When you see a display like Draw D-isoleucine: and you draw the lines and atomic symbols like the drawing below left, the display will show isoleucine, Draw D-isoleucine.  Complete the two wedges like in the drawing below right by drawing (in one stroke) a figure that looks like a 7 or an L between two points that already have a line between them.  The wedge means that the atom at the end of the stroke is in front of the atom at the beginning of the stroke.  Double tap on the paper twice to retry the same question but change the direction of the wedges to see how the structure name changes.
CcHhNnOoSs The molecular formula is displayed because the program does not know the name of your drawing.
No bond? Your line was not straight, you drew a wedge between two points that did not have a line between them or you drew an atomic symbol before its bond.
Please wait... If the recognition of your drawing is taking too long, exit the program.
Tap Twice to Erase! You double tapped once.  You have to double tap again or continue drawing.
Unknown Element? You entered an atomic symbol besides C, H, N, O or S or you drew a bond that was too short.

*Different auditory clues are provided for each operation.



  • Amino acids or more precisely alpha-amino carboxylic acids are the building blocks of poly-peptides, proteins, and enzymes, the molecular machinery of cells.
  • You have to learn to draw them for biochemistry.
  • They consist of a methine (CH) carbon connecting an amino group (NH2), a carboxyl function (CO2H) and a group R that varies.
  • The simplest amino acid is glycine (the major component of gelatin but don't ask where it comes from) in which R is hydrogen.
  • This program recognizes the following amino acids:  alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, and valine.
  • Except for glycine, the methine carbon has four different groups attached and arranged around it like a tetrahedron and in an asymmetric fashion like your right and left hands.
  • These center of asymmetry are called chiral centers.
  • The arrangement of the four different groups around a chiral center are designated by the letters D or L and in this program by using wedges.
  • Isoleucine and threonine contain two chiral centers.
  • The term allo-isoleucine or allo-threonine refer to having the incorrect arrangement of four groups at the second chiral center in these structures.
  • If you are familiar with the Cahn-Ingold-Prelog (CIP) rules of denoting three-dimensional arrangement, except for cysteine, the (R) configuration in wedges denotes the D configuration in Fischer projections and the (S) configuration in wedges denotes the L configuration in Fischer projections.
  • This program does not recognized Fischer projections.
  • For tryptophan, both ways of drawing the alternate single and double bonds in the benzene ring are allowed.
  • Amino acids really exist as alpha-ammonium carboxylates because amino group are basic and carboxylic acids are acidic and side groups may also be protonated or deprotonated but this program does not assume that.

A list of Amino Acids (as provided in the Quiz Mode) that this program can recognize (D and L versions require using wedges to draw.):

  1. alanine
  2. L-alanine
  3. D-alanine
  4. arginine
  5. L-arginine
  6. D-arginine
  7. asparagine
  8. L-asparagine
  9. D-asparagine
  10. aspartic acid
  11. L-aspartic acid
  12. D-aspartic acid
  13. cysteine
  14. L-cysteine
  15. D-cysteine
  16. glutamic acid
  17. L-glutamic acid
  18. D-glutamic acid
  19. glutamine
  20. L-glutamine
  21. D-glutamine
  22. glycine
  23. histidine*
  24. L-histidine*
  25. D-histidine*
  26. isoleucine
  27. L-isoleucine
  28. D-isoleucine
  29. L-allo-isoleucine
  30. D-allo-isoleucine
  31. leucine
  32. L-leucine
  33. D-leucine
  34. lysine
  35. L-lysine
  36. D-lysine
  37. methione
  38. L-methione
  39. D-methione
  40. phenylalanine
  41. L-phenylalanine
  42. D-phenylalanine
  43. proline
  44. L-proline
  45. D-proline
  46. serine
  47. L-serine
  48. D-serine
  49. threonine
  50. L-threonine
  51. D-threonine
  52. L-allo-threonine
  53. D-allo-threonine
  54. tryptophan
  55. L-tryptophan
  56. D-tryptophan
  57. tyrosine
  58. L-tyrosine
  59. D-tyrosine
  60. valine
  61. L-valine
  62. D-valine

*Please note that there are two ways of drawing histidine, one with hydrogen on one ring nitrogen and the corresponding double bonds in the ring and one with hydrogen on the other ring nitrogen and the corresponding double bonds in the ring, but with the demise of Livescribe Developer Program only one drawing was included as pictured in the link below.

An example of Amino Acids that this program can recognize.




MusicComposer ] [ Amino Acids ] Acyclic Alkanes ]

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