Difference between revisions of "Kevin Wyllie Week 3"

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(Formatting edit, in hopes of making the levels of sub-headings more clear.)
(That didn't work. For the time being, the headings may just look a little confusing.)
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===Journal Week 3===
 
===Journal Week 3===
  
====Complement of a Strand==== ----
+
====Complement of a Strand====  
  
 
[[Image:Kwscreenshot1.jpg|right|thumb]]
 
[[Image:Kwscreenshot1.jpg|right|thumb]]
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  5'- gttaaaatgccgccagcggaactggcggctgggttatacgcggaacatggtattaggcaacgtttcaagttcaatattgtcttctttggccatcgtacctattgaaatatagtaga -3'
 
  5'- gttaaaatgccgccagcggaactggcggctgggttatacgcggaacatggtattaggcaacgtttcaagttcaatattgtcttctttggccatcgtacctattgaaatatagtaga -3'
  
====Reading Frames==== ----
+
====Reading Frames====  
  
 
''The original sequence in the prokaryote.txt file will be assumed to be the top strand for this exercise.''
 
''The original sequence in the prokaryote.txt file will be assumed to be the top strand for this exercise.''

Revision as of 00:57, 20 September 2015

Journal Week 3

Complement of a Strand

Kwscreenshot1.jpg
  • Shown in green: the following command is used to open the file (using prokaryote.txt as an example).
cat prokaryote.txt
  • Shown in red: the following command is used to sequence the complementary strand (in the 5' -> 3' direction - thus the "rev" command).
cat prokaryote.txt | sed "y/atgc/tacg/" | rev
  • Finally, the sequence of the complementary strand is (copy/pasted from the command line window):
5'- gttaaaatgccgccagcggaactggcggctgggttatacgcggaacatggtattaggcaacgtttcaagttcaatattgtcttctttggccatcgtacctattgaaatatagtaga -3'

Reading Frames

The original sequence in the prokaryote.txt file will be assumed to be the top strand for this exercise.

+1, +2, and +3 Frames
Kwscreenshot2.jpg
  • Shown in green: to separate the strand into codons (resulting in the +1 frame):
cat prokaryote.txt | sed "s/.../& /g"
  • Shown in red: to convert to the mRNA sequence (treating the DNA stand as the mRNA-like strand):
cat prokaryote.txt | sed "s/.../& /g" | sed "y/t/u/"
  • Shown in blue: to translate this mRNA sequence:
cat prokaryote.txt | sed "s/.../& /g" | sed "y/t/u/" | sed -f genetic-code.sed
  • For the +2 frame, the final pipe can be slightly altered:
cat prokaryote.txt | sed "s/^.//g" | sed "s/.../& /g" | sed "y/t/u/" | sed -f genetic-code.sed
  • And similarly, for the +3 frame:
cat prokaryote.txt | sed "s/^..//g" | sed "s/.../& /g" | sed "y/t/u/" | sed -f genetic-code.sed