The staining procedure is rapid, and results are obtained 90 minutes after electrophoresis of the sequencing reactions. Sequencing results may be permanently captured on EDF Film in a manner similar to data generated using radioactive labels. As with all sequencing methods, template purity affects the sequencing results. Figure 1 summarizes these protocols. 4,766,072 has been issued to Promega Corporation for transcription vectors having two different bacteriophage promoter sequences separated by a series of unique restriction sites into which foreign DNA can be inserted.
Plasmid template purification procedures.
All vendors supply the necessary solutions except TE buffer. We found that the template isolated by one procedure appeared to contain impurities, as indicated by the ambiguous results obtained. This result may be interpreted as RNA contamination of the template, resulting in false priming sites. Templates were purified according to the procedures outlined in Figure 1 . Our results demonstrate that the choice of DNA purification system used may affect the quality of sequence data obtained from plasmid templates.