Figure 2.
Qualitative control PCRs for the detection of C. ljungdahlii and C. kluyveri in the reactor. We used specific primer pairs for the detection of either C. ljungdahlii (Cl) or C. kluyveri (Ck) in the reactor during the operating period. As a negative control, we used MilliQ water (H2O). Primer pairs were tested for cross reactions by using C. ljungdahlii genomic DNA (Cl gDNA) or a pure culture of C. ljungdahlii (Cl culture) or C. kluyveri (Ck culture) as template for each of the primer pairs. (A) Each pocket of the agarose gel was loaded with 10 μL of a 50 μL PCR reaction. (B) Each pocket was loaded with 40 μL of a 50 μL PCR reaction. Because only faint bands were detected for the C. kluyveri specific PCR, visible bands are highlighted with a red box. M, DNA marker (HyperLadder 1kb, Bioline, Singapore).