Lab journal task 8
Mutation selection
10 mutations were randomly selected from HGMD and dbSNP.
Mutation analysis
The description of the physicochemical properties is based on the entry for amino acids in wikipedia.
The mutations were visualized with Pymol. Because the pdb structure 1A6Z starts at position 22 in the reference structure, we subtracted 22 from the codon position to get the position of the mutation in the structure. The mutatins were done following the description in Use PyMOL for this. We did mutations for the first 9 SNPs but the last one (Arg330Met) could not be visualized, because the pdb structure is shorter than the reference sequence and only contains the residues 22 to 297. The rotamer for each mutated residue was selected based on the orientation and the size and color of the discs. We selected the rotamers with the least and smallest red discs if there was none without. For residues that are located on the border of the protein, we also tried to find rotamers that are not pointed into the solvent.
The secondary structure of the location of the mutation was taken from the DSSP assignment of the 1A6Z_A structure.
The BLOSUM62 matrix was taken from BLOSUM62 and the PAM250 matrix from PAM250.
PSSM fom PsiBlast with 5 iterations and default parameters using the /mnt/project/pracstrucfunc13/data/big/big_80 database:
blastpgp -i /mnt/home/student/betza/data/hfe.fasta -d /mnt/project/pracstrucfunc13/data/big/big_80 -j 5 -o /mnt/home/student/betza/task8/psiblast/iter5_big80.results -Q /mnt/home/student/betza/task8/psiblast/iter5_big80.pssm -C /mnt/home/student/betza/task8/psiblast/iter5_big80.chk
The resulting PSSM is the following (only the 10 mutation positions are shown):
Last position-specific scoring matrix computed, weighted observed percentages rounded down, information per position, and relative weight of gapless real matches to pseudocounts A R N D C Q E G H I L K M F P S T W Y V A R N D C Q E G H I L K M F P S T W Y V Arg330Met 53 V -3 -6 -7 -7 -3 -6 -6 -7 -2 0 4 -6 1 -1 -6 -4 -5 -6 -5 6 2 0 0 0 1 0 0 0 1 4 37 0 3 2 0 1 0 0 0 47 1.32 inf 63 H -3 -1 2 -3 1 -5 -4 -1 0 -4 -5 0 -3 -7 -3 6 -1 -2 -7 -5 1 3 8 2 3 0 1 5 2 1 1 5 1 0 1 62 4 1 0 1 1.26 inf 67 R -3 5 0 -3 -3 2 0 -3 -1 -2 -3 3 -2 -6 -2 0 2 -1 -5 -4 2 33 4 1 1 7 5 2 1 2 2 16 1 0 2 5 13 1 0 1 0.69 inf 97 M -1 0 0 0 2 0 0 -1 2 0 -1 0 2 1 0 -1 0 4 1 -1 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 0.09 inf 130 N -4 0 2 0 -2 -2 -1 5 -2 -2 -4 0 -1 -4 -4 -1 2 -1 -6 -3 1 5 10 4 1 2 4 40 1 3 2 5 1 1 1 5 11 1 0 2 0.67 inf 168 E -3 1 -1 -2 -3 -1 0 -3 -2 0 1 4 0 0 -3 -3 -3 0 2 0 2 6 4 2 1 2 7 2 1 6 14 22 2 4 2 3 1 1 7 6 0.29 inf 183 L -4 -3 -3 -4 -2 -4 -4 -5 -1 1 5 -2 2 -1 -4 -3 -3 -1 1 2 2 2 1 1 1 1 1 1 1 6 45 3 4 3 1 2 2 1 5 13 0.68 inf 217 T 0 -3 -2 0 -5 -1 -1 1 -1 -3 1 -2 -1 -3 3 3 0 -6 -1 -1 8 1 1 4 0 3 3 10 1 1 12 2 1 1 15 22 6 0 2 5 0.30 inf 282 C -6 -6 -8 -9 12 -8 -9 -8 -8 -7 -7 -8 -7 -5 -8 -5 -6 -8 -5 -6 0 1 0 0 94 0 0 0 0 0 0 0 0 1 0 1 0 0 1 0 4.31 inf 330 R -5 5 -4 -6 1 -1 -5 -6 2 -5 -5 3 -3 0 -5 -4 -5 8 4 -6 1 28 1 0 3 2 0 0 4 1 1 18 0 3 1 1 0 23 14 0 1.41 inf
The mutations are marked in purple.