Figure 4.

Mass spectra of PCR products generated from T. thermophilus dnaX mRNA (cDNA) or genomic DNA. The molecular mass is shown on the x axis, and the relative intensity of the signal is indicated on the y axis. (A) Distribution of PCR products from the cDNA template. Two single-strand products are evident for each PCR fragment. The number of A or T residues in the homopolymeric run is shown above each peak. The measured and predicted masses of each peak are shown in C. When the PCR products contain 14 A/T, the masses of the single strands are not resolved and appear as a single peak. (B) Distribution of PCR products from genomic DNA. The number of A or T residues is shown above each peak. The measured and predicted masses of each peak are shown in C. (C) Tabulation of the measured and predicted masses of the PCR product single strands. The difference between predicted and measured masses is expressed as the percentage error for each peak.