Question

You find a new gene involved in metabolizing plastics. You decide to search for other potential plastic metabolizing bacteria by using primers that amplify that sequence. When you perform PCR on your different sample sets from local landfills, you find that every sample is positive for the plastic degrading gene of interest. Unfortunately you also realize that you forgot a negative control, and are concerned you contaminated your samples. What would be an effective negative control?

A. No Sample
B. No polymerase
C. No dNTPs
D. No Buffer

Answer 1

The most effective negative control in this case would be the option B: No polymerase. By omitting the polymerase, you can ensure that any positive results obtained in the other samples are due to the presence of the plastic degrading gene of interest and not contamination.

Step-by-step explanation:

A negative control in this experiment would be a sample where none of the components necessary for the PCR reaction are present. This means that all of the options A, B, C, and D could be potential negative controls. However, the most effective negative control in this case would be the option B: No polymerase. By omitting the polymerase, you can ensure that any positive results obtained in the other samples are due to the presence of the plastic degrading gene of interest and not contamination. Without the polymerase, DNA amplification cannot occur, regardless of whether the samples are contaminated or not.