Evolutionary Response of Escherichia coli to Thermal Stress

1993 ◽  
Vol 142 ◽  
pp. S47-S64 ◽  
Author(s):  
Richard E. Lenski ◽  
Albert F. Bennett
2013 ◽  
Vol 13 (1) ◽  
pp. 50 ◽  
Author(s):  
Alejandra Rodríguez-Verdugo ◽  
Brandon S Gaut ◽  
Olivier Tenaillon

2017 ◽  
Vol 51 (1) ◽  
pp. 112-121 ◽  
Author(s):  
A. R. Kayumov ◽  
M. I. Bogachev ◽  
V. A. Manuvera ◽  
V. N. Lazarev ◽  
A. V. Sabantsev ◽  
...  

2019 ◽  
Author(s):  
Andrés Mesas ◽  
Angélica Jaramillo ◽  
Luis E. Castañeda

AbstractGlobal warming imposes important challenges for ectotherm organisms, which can avoid the negative effects of thermal stress via evolutionary adaptation of their upper thermal limits (CTmax). In this sense, the estimation of CTmax and its evolutionary capacity is crucial to determine the vulnerability of natural populations to climate change. However, these estimates depend on the thermal stress intensity and it is not completely clear whether this thermal stress intensity can impact the evolutionary response of CTmax and thermal reaction norms (i.e. thermal performance curve, TPC). Here we performed an evolutionary experiment by selecting high heat tolerance using acute and chronic thermal stress in Drosophila subobscura. After artificial selection, we found that knockdown temperatures (a CTmax proxy) evolved in selected lines compared to control lines, whereas the realized heritability and evolutionary rate change of heat tolerance did not differ between acute-selected and chronic-selected lines. From TPC analysis, we found acute-selected lines evolved a higher optimal performance temperature (Topt) compared to acute-control lines, whereas this TPC parameter was not different between chronic-selected and chronic-control lines. The evolutionary response of Topt caused a displacement of entire TPC to high temperatures suggesting a shared genetic architecture between heat tolerance and high-temperature performance, which only arose in the acute-selected lines. In conclusion, thermal stress intensity has important effects on the evolution of thermal physiology in ectotherms, indicating that different thermal scenarios conduce to similar evolutionary responses of heat tolerance but do not for thermal performance. Therefore, thermal stress intensity could have important consequences on the estimations of the vulnerability of ectotherms to global warming.


1991 ◽  
Vol 54 (2) ◽  
pp. 90-93 ◽  
Author(s):  
CAROLINE E. O'NEILL ◽  
GARY K. BISSONNETTE

Four strains of Escherichia coli were examined for response to heat stress (60°C) as a function of physiological age and antecedent oxygen growth conditions. Exponential phase cells were more susceptible to heat than cells grown to the stationary phase. Anaerobically grown, exponential phase cells were more susceptible to thermal stress than were cells grown to a similar physiological state but under aerobic conditions. In the case of stationary phase cells, differences in response to heat stress as related to prior oxygen growth conditions were equivocal. Repair characteristics of thermally injured cells were also examined. Cells grown anaerobically prior to heat stress required 1.5 h longer than their aerobically grown counterparts to complete repair. These findings suggest that antecedent oxygen growth conditions influence the response of E. coli to thermal stress and perhaps, more generally, that persistence of environmentally stressed enteric microorganisms must be considered in relation to prior oxygen growth conditions in vivo.


2009 ◽  
Vol 276 (1676) ◽  
pp. 4139-4148 ◽  
Author(s):  
Todd C. LaJeunesse ◽  
Robin T. Smith ◽  
Jennifer Finney ◽  
Hazel Oxenford

Reef corals are sentinels for the adverse effects of rapid global warming on the planet's ecosystems. Warming sea surface temperatures have led to frequent episodes of bleaching and mortality among corals that depend on endosymbiotic micro-algae ( Symbiodinium ) for their survival. However, our understanding of the ecological and evolutionary response of corals to episodes of thermal stress remains inadequate. For the first time, we describe how the symbioses of major reef-building species in the Caribbean respond to severe thermal stress before, during and after a severe bleaching event. Evidence suggests that background populations of Symbiodinium trenchi ( D1a ) increased in prevalence and abundance, especially among corals that exhibited high sensitivity to stress. Contrary to previous hypotheses, which posit that a change in symbiont occurs subsequent to bleaching, S. trenchi increased in the weeks leading up to and during the bleaching episode and disproportionately dominated colonies that did not bleach. During the bleaching event, approximately 20 per cent of colonies surveyed harboured this symbiont at high densities (calculated at less than 1.0% only months before bleaching began). However, competitive displacement by homologous symbionts significantly reduced S. trenchi 's prevalence and dominance among colonies after a 2-year period following the bleaching event. While the extended duration of thermal stress in 2005 provided an ecological opportunity for a rare host-generalist symbiont, it remains unclear to what extent the rise and fall of S. trenchi was of ecological benefit or whether its increased prevalence was an indicator of weakening coral health.


2017 ◽  
Vol 29 (2) ◽  
pp. 91 ◽  
Author(s):  
Rui Li ◽  
Yage Shi ◽  
Bo Ling ◽  
Teng Cheng ◽  
Zhi Huang ◽  
...  

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