David Liu, same guy from last homework, also isolated a cDNA clone from snake
venom library. The nucleotide sequence of this cDNA clone is shown here:
AAAACCATCAAATATGTTATGCTGGAATGCAACGAACTGATCCCGCTGTTC
TACGAAACCTGCCCGGCTGGTGAAAACATCTGCTACGAAATGTTCATGGTT
GCTACCCCGAAAGTTCCGTGCGAACGTGGTTGCATCGACGTTTGCCCGGAA
TCTTCTCTGATCGTTAAATACGTTTGCTGCAACACCGACCGTTGCCAGTAAT
CCAGCGCCTGATCTCTCGAAATAAAAGCCGCATTG
(1) Please help him to find its corresponding polypeptide sequence (DNA -> Protein
translation).
MLECNELIPL FYETCPAGEN ICYEMFMVAT PKVPCERGCI DVCPESSLIV KYVCCNTDRCQ
(61 amino acids)
(2) Please help him to calculate pI/Mw of thispolypeptide, perform the trypsin cutting ,
analyze the cutting pattern and report the fragments with molecular weight over 500
Dalton.
[Theoretical pI/Mw: 4.29 / 6917.13 ]
mass position peptide sequence
---------- --------- ----------------
3699.66 1- 32 MLECNELIPLFYETCPAGENICYEMFMVATPK
1462.73 38- 51 GCIDVCPESSLIVK
973.39 52- 59 YVCCNTDR
603.29 33- 37 VPCER
(3) Please help him to identify this toxin. Is it a new toxin?
No. It is a venom produced by "NAJA SPUTATRIX" (MALAYAN SPITTING COBRA).
For more information, please go to http://www.expasy.ch/cgi-bin/get-sprot-entry?Q02454
(4) Please help him to use Prosite scanning tool to find out possible functions or pattern
of this polypeptide.
1 PDOC00005 PS00005 PKC_PHOSPHO_SITE (Protein kinase C phosphorylation site)
Number of matches: 2
1 30-32 TPK
2 57-59 TDR
2 PDOC00245 PS00272 SNAKE_TOXIN (Snake toxins signature)
38-58 GCIDVCPESSLIVKYVCCNTD
(5) David would like to see its structure. Could you help him to find structure of this
toxin or make a model if it is a new protein? Show structure on your homwpage ( 3
different views).