HOMEWORK#5

Sequence comparison / Homology search

• due on 12/17

• Shirley Lee, a student in department of Life Sciences, was bitten by a snake in the backyard of life science building. She was so angry! Thus, she killed the snake and purified several toxins from its venoms. She sequenced one of the toxin, got this sequence:

  1 L K C N K L V P L F Y K T C P A G K N I C Y K M F M V A T P

  31 K L P V K R G C I D V C P K S S L L V R Y V C C N T D K C N

  (1) Is this a new toxin? Please help him to identify this toxin.

  Since no protein which is totally identical to this toxin can be found, it should be identified as a new one. The existing sequence with best sequence identity to it is only of 93% identical.

  (2) Can you find proteins that share sequence homology with this toxin? Show them in multiple alignment form.

  This is the homology sequence align of the new protein.

  (3) Please predict its secondary structure.

  This is the pridicted secondary structure.

  (4) Please show its charge distribution.

  This is the charge distribution computed by SAPS program.