S-STEM Scholar Jessica Sabel's Blog

  Introduction:   The goals for this week were to finish with our MIC testing on  D. aquaticu s, as well as beginning our antibiotic testing with three new species of  Deinococcus  that were plated last week. The species chosen for our first part of antibiotic testing were  D. grandis ,  D. roseus , and  D. indicus . These species were chosen because they are fast growing, as well as being easier species to start testing on. The goal is to work on the easier species while we work to master our protocols and technique, then move on to the more difficult species as our project progresses.  D. grandis  and  D. indicus  are gram negative rods that grow in TGY. Like many of the  Deinococcus  species, they often stain gram positive due to their thick cell wall. Despite their appearance, they are classified as gram negative because their structure closely resembles gram negative bacteria. However,  D. roseus  is co...

Introduction:    This week we are continuing our minimum inhibitory concentration (MIC) testing with  D. aquaticus . Based on testing performed last semester, we chose our concentrations of tetracycline to be 100 ng/ml, 10 ng/ml, 1 ng/ml, and 0 ng/ml. We expect to see growth on 0 ng/ml because there is no antibiotic added. As for the plates with antibiotic included, we hope to see growth on the 1 ng/ml plate and no growth on the 10 ng/ml and 100 ng/ml plate. If the results are consistent with our goal for the project, we can correctly identify the MIC for  D. aquaticus  and move forward with testing on other species of  Deinococcus .   Methods:   Our sample of  D. aquaticus  that was inoculated on 01/26 was contaminated with fungus, so a new sample was inoculated and placed in the incubator on 01/31.   The 4 125 ml flasks were stored to the side after being autoclaved. We collected these flasks and set them up to be heated up. We us...