Fig.3 SDS-PAGE of proteins purified from E.coli cells containing or lacking the gene encoding Taq DNA polymerase. Lane 1-4 and lane 5-8 contained samples from two groups respectively. Proteins were extracted from cell lysate containing recombinant plasmid with the taq gene (pTaq2) or control plasmid (pControl) without the taq gene. Taq DNA polymerase protein was marked in red boxes. Lane 1, 3, 5 and 7, 5 μl of respective samples were loaded in each lane. Lane 2, 4, 6 and 8, 20 μl of respective samples were loaded in each lane.