Team:Michigan/Results
Results
Experiment #1: How do different promoters in pThermolyze affect cell growth at 37C and 25C?
We performed this experiment three times, but it proved difficult to ensure all cultures began at 0.2-0.4 OD, so for our analysis, we discarded the data for all trial runs that did not start with a time 0 OD of 0.2-0.4. If we had not done this, we would be comparing cultures that were at very different stages of growth. The remaining data are shown in the table below. Unfortunately, this method of pruning the data for consistency meant that we did not have any valid trials for promoter J grown at 37C and only one trial for that promoter at 25C, so we have excluded promoter J from our analysis. As the weakest of the three promoters that we tested, it is unlikely that its exclusion impacts the results. We see no consistent drop in OD at any time point once the cultures with our killswitch and promoters were switched to incubating at 25C. Such a drop would have indicated our killswitch was lysing cells as we had hoped.
| Trial | Sample | Time 0 | 0:20 | 0:40 | 1:00 | 1:20 | 1:40 | 2:00 | 2:20 | 2:40 | 3:00 | 3:20 | 3:40 | 4:00 | 4:20 | 4:40 | 5:00 | 5:20 | 5:40 | 6:00 |
| 1 | P-25 | 0.354 | 0.379 | 0.497 | 0.44 | 0.471 | 0.497 | 0.573 | 0.621 | 0.601 | 0.694 | 0.803 | 0.912 | 0.951 | 1.132 | 1.077 | 1.246 | 1.505 | 1.362 | 1.484 |
| 2 | P-25 | 0.33 | 0.365 | 0.447 | 0.473 | 0.507 | 0.638 | 0.657 | 0.777 | 0.913 | 0.945 | 1.045 | 1.162 | 1.321 | 1.301 | 1.525 | 1.666 | 1.782 | ||
| 1 | C-25 | 0.297 | 0.346 | 0.474 | 0.388 | 0.46 | 0.449 | 0.495 | 0.59 | 0.634 | 0.668 | 0.717 | 0.883 | 0.856 | 0.964 | 1.096 | 1.029 | 1.207 | 1.126 | 1.287 |
| 2 | C-25 | 0.243 | 0.262 | 0.302 | 0.311 | 0.373 | 0.44 | 0.462 | 0.507 | 0.562 | 0.585 | 0.639 | 0.747 | 0.806 | 0.828 | 0.879 | 0.977 | 1.1 | ||
| 3 | C-25 | 0.268 | 0.32 | 0.287 | 0.306 | 0.309 | 0.415 | 0.409 | 0.472 | 0.502 | 0.545 | 0.684 | 0.67 | 0.763 | 0.754 | 0.853 | 0.929 | 0.884 | 0.998 | 1.06 |
| 1 | T-25 | 0.258 | 0.233 | 0.287 | 0.277 | 0.268 | 0.335 | 0.304 | 0.442 | 0.33 | 0.436 | 0.479 | 0.463 | 0.649 | 0.549 | 0.555 | 0.681 | 0.599 | 0.794 | |
| 3 | T-25 | 0.293 | 0.319 | 0.307 | 0.312 | 0.359 | 0.498 | 0.449 | 0.502 | 0.535 | 0.604 | 0.689 | 0.697 | 0.756 | 0.911 | 0.935 | 0.96 | 0.992 | 1.062 | 1.109 |
| 2 | J-25 | 0.368 | 0.505 | 0.541 | 0.603 | 0.712 | 0.862 | 0.863 | 0.962 | 1.064 | 1.169 | 1.301 | 1.421 | 1.611 | 1.734 | 1.846 | 2.059 | 2.236 | ||
| 1 | L-25 | 0.28 | 0.371 | 0.468 | 0.374 | 0.413 | 0.423 | 0.553 | 0.581 | 0.595 | 0.633 | 0.715 | 0.755 | 0.839 | 0.984 | 1.106 | 1.095 | 1.225 | 1.33 | 1.341 |
| 2 | L-25 | 0.36 | 0.431 | 0.435 | 0.533 | 0.604 | 0.741 | 0.776 | 0.841 | 0.952 | 1.123 | 1.175 | 1.286 | 1.517 | 1.671 | 1.681 | 1.921 | 2.11 | ||
| 1 | P-37 | 0.354 | 0.554 | 0.726 | 0.929 | 1.157 | 1.41 | 1.642 | 2.026 | 2.276 | 2.43 | |||||||||
| 1 | C-37 | 0.363 | 0.646 | 0.658 | 0.913 | 1.025 | 1.227 | 1.492 | 1.718 | 2.061 | 2.35 | 2.452 | ||||||||
| 2 | C-37 | 0.362 | 0.513 | 0.724 | 0.992 | 1.126 | 1.37 | 1.598 | 1.896 | 2.1 | 2.249 | |||||||||
| 3 | C-37 | 0.331 | 0.472 | 0.773 | 1.033 | 1.212 | 1.428 | 1.604 | 1.991 | 2.187 | 2.465 | |||||||||
| 1 | T-37 | 0.235 | 0.342 | 0.392 | 0.512 | 0.59 | 0.657 | 0.893 | 1.117 | 1.43 | 1.595 | 1.857 | 1.999 | 2.385 | ||||||
| 2 | T-37 | 0.213 | 0.249 | 0.315 | 0.437 | 0.53 | 0.736 | 0.895 | 1.093 | 1.369 | 1.531 | 1.893 | 2.208 | 2.339 | ||||||
| 3 | T-37 | 0.291 | 0.523 | 1.003 | 0.998 | 1.161 | 1.41 | 1.636 | 1.948 | 2.283 | 2.439 | |||||||||
| 1 | L-37 | 0.332 | 0.706 | 0.744 | 1.023 | 1.223 | 1.433 | 1.718 | 2.275 | 2.443 |
For the remaining trials, we calculated generation time from 20 minutes after half the cultures were switched to 25C until the 100 minute time point. We used the formula 80/(3.3*Log(Abs100/Abs20)), to calculate the generation time. We chose these two time points because after 20 minutes at 25C, the cultures should have cooled to their new temperature and stabilized, and 200 minutes was the last time point where no culture went over the measurable limit of 2.5 OD.
