5.4 Vorbereitete Lernsequenzen
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What are the complete names of the last four amino acids in
this protein?
2. Investigate any five genes of your choice, by clicking on their
arrows on the gene map for Mycoplasma genitalium. Identify the
first five and the last five acids for the peptides encoded by each
gene. Also identify the first three bases and the last three bases.
Now examine your data to see if there are any regularities.
Are there any similarities in the amino acids that begin
peptides?
Are there any similarities in the amino acids that terminate
peptides?
Is the first codon always a start codon?
Is the last codon listed a stop codon?
State a hypothesis regarding the first amino acid of peptides.
Now test that hypothesis by looking at genes MG001 and MG099
(click their symbols on the gene map for Mycoplasma genitalium).
Is your hypothesis supported?
3. Let's retrieve a small portion of the unedited DNA sequence
from the TIGR Position Search and Segment Retrieval page.
Bases are numbered from 1 to 580,070. Let's find the beginning
of the gene MG042 that we introduced above. We need to tell the
database to retrieve the DNA sequence between any two
positions, and we know from the MG042 Report that this gene
starts at position 50060. Let's ask for positions 50040 and 50080,
so we can see 20 bases on either side of the start codon. Make
sure your settings match those shown below, then press
"Submit."
You should see a DNA sequence of about 40 bases. If you see
something else, then you didn't set the "Retrieve sequence
segment" button correctly. Check the diagram above to be sure
your settings are correct and try again.
Now compare this with the sequence for the beginning of gene
MG042 that you isolated above:
TIGR: The Institute for
Genome Research
Abb. 5-8
Suchformular der
Datenbank
