Бактерии не смогли адаптироваться к новому антибиотику

> Адаптация-неадаптация бактерий к антибиотикам - это, скорее, вероятностное событие. Рано или поздно
> все равно появится мутант, которому теиксобактин будет параллелен.

Тут вопрос в том, насколько поздно. Если через миллиард поколений, то это не страшно.
Если почитать оригинал статьи, то можно узнать условия эксперимента, в ходе которых пытались получить устойчивые штаммы:

«Resistance studies.

In order to determine a suitable concentration of teixobactin for single-step selection for resistance, we first determined a minimal concentration for which no resistant mutants are observed, usually referred to as MPC.
The MPC for S. aureus ATCC 29213 was determined by plating 109 12 cells per plate onto 10 MHA plates containing 1xMIC, 1.25xMIC, 1.5xMIC, 1.75xMIC, 2xMIC, 2.25xMIC, and 2.5xMIC teixobactin. After 48 hours of incubation, the plates were examined for colonies. There were no colonies on plates with ≥2xMIC teixobactin. Note that the intrinsic variability in determining MIC is also 2 fold, this means that even at a very low concentration of the compound, there was no resistance development.
Next, we performed sequential culturing of S. aureus in the presence of subinhibitory levels of teixobactin in order to increase the probability of obtaining resistant mutants. S. aureus ATCC 29213 cells were grown in 1 mL of media (MHB with 0.002% polysorbate 80) containing teixobactin at different concentrations. Ofloxacin was included as a control.
Cells were added to teixobactin present at 0.25xMIC, 0.5xMIC, 1xMIC, 2xMIC and 4xMIC. At 24 hour intervals, the cultures were checked for growth. Cultures from the second highest concentrations that allowed growth (OD600 ≥2) were diluted 1:100 into fresh media containing 0.25xMIC, 0.5xMIC, 1xMIC, 2xMIC and 4xMIC of teixobactin. This serial passaging was repeated daily for 30 days. Any cultures that grew at higher than the MIC levels were passaged on drug free MHA plates and the MIC was then determined by broth microdilution. No resistant mutants were obtained. This experiment was repeated, and produced the same negative result.
In order to maximize the chance of obtaining a resistant mutant, we performed an additional experiment with very small incremental increases in the drug concentration. Cells were added to a series of tubes with small differences in the concentration of teixobactin (0.06xMIC, 0.25xMIC, 0.5xMIC, 0.75xMIC, 1xMIC, 1.25xMIC, 1.5xMIC, and 2xMIC). At 24 hour intervals, cultures from the highest concentration that allowed growth to a minimum OD600 of 0.2 were diluted 1:100 into fresh medium containing 0.06xMIC, 0.25xMIC, 0.5xMIC, 0.75xMIC, 1xMIC, 1.25xMIC, 1.5xMIC, and 2xMIC. This passaging was repeated for 27 days. Cultures that grew at levels higher than the MIC were passaged on drug free MHA plates, and the MIC was determined. For teixobactin, there were no mutants with an MIC greater than the parent S. aureus ATCC 29213».