Image unavailable: Diagram showing the conversion of ATP to methylthioadenosine. ATP loses pyrophosphate to form DMAPP, which then becomes MTA. Chemical structures and bonds are depicted throughout.Figure 5.8.2: Sample DNA Sequencing
The DNA to be sequenced is prepared as a single strand. This template DNA is supplied with
a mixture of all four normal (deoxy) nucleotides in ample quantities
dATP
dGTP
dCTP
dTTP
a mixture of all four dideoxynucleotides, each present in limiting quantities and each labeled with a "tag" that fluoresces a different color:
ddATP
ddGTP
ddCTP
ddTTP
DNA polymerase I
Image unavailable: Colorful DNA sequencing chromatogram with four rows of peaks in red, yellow, black, and gray, each representing different nucleotide bases.Figure 5.8.3 example of a DNA sequence (455 nucleotides of the lysU gene of E. coli) courtesy of Pharmacia Biotech Inc., Piscataway, NJ
