Hello again! So yesterday we ran the bacterial DNA that had been amplified using PCR on a gel to see if 1) we actually did everything correctly and didn’t contaminate our samples, and 2) If our plant samples had bacterial DNA in them. The picture of our gel is below, it’s kind of hard to read, but we got DNA in our positive control lane (which is what we wanted to see), but we also saw a line in our negative control lane (far right), which indicates that there was some kind of bacterial DNA present in our negative control, indicating contamination, which is disappointing. However, all of our other samples look good, so our preliminary data indicates that both bamboo samples and the dicot sample were positive for bacterial DNA, but that conifer didn’t have any (apparently conifers tend to have less bacteria than other plant types), so that’s a good sign. Since our negative control was contaminated, we had to redo PCR over the weekend, and sometime in the next few days we’ll re-run our gel and hope that the negative control isn’t contaminated! On a positive note, our spread plates of bacteria seem to be growing really well, particularly a plate of neon pink colonies, which is exciting!
Fun bacterial fact of the day: based on our work with bamboo plants, Professor Okeke suggested that my partner and I read an article in PNAS, “Evidence of cellulose metabolism by the giant panda microbiome,” (L. Zhu, Q. Wu, J. Dai, S. Zhan and F. Wei. (2011) Evidence of cellulose metabolism by the giant panda microbiome. PNAS 108, 17714-17719), which discusses the bacteria present in the digestive system of the panda. Apparently, pandas’ preference for bamboo changes during different months of the year (it’s lowest during the summer), and during that time they eat different parts of the bamboo plant. This change in bamboo preference corresponds to a change in the microorganism community of the panda’s GI tract. Perhaps the phyllosphere of the bamboo leaf has something to do with this change in dietary preference?