Effect of temperature change on bacterial virulence
This publication is copyrighted. You may download, display and print it for Your own personal use. Commercial use is prohibited.
Abiotic factors such as temperature can influence the evolution of the pathogens, but empirical evidence on this is very scarce. The pathogen Serratia marcescens, which had evolved under three different temperature treatments for 1 month, and ancestor (ATCC 13880) of the evolved strains, were tested for their virulence in Galleria mellonella- wax moth. Bacteria injected larvae were incubated in two different temperatures to explore phenotypic plasticity in virulence. The mortality of the hosts was recorded and analysed. Survival analysis with linear mixed-effects model in R revealed that temperature change affected the bacteria virulence. Ancestor and those strains that had evolved in constantly high 38°C temperature were found to exhibit high virulence whereas strains evolved in benign 31°C, constant or fluctuating (daily fluctuations between 24-38°C) were found to have attenuated virulence. Whole genome sequencing of evolved strains n=28 revealed putative and new virulence factors. My results show that high temperatures are able to maintain and select for genes increasing virulence. If my result reflects things in the wild and also in other pathogens results mean problems associated with increasing mean temperatures due to global change . ...
MetadataShow full item record
- Pro gradu -tutkielmat 
Showing items with similar title or keywords.
Exploring evolutionary responses to increasing temperature in an environmental opportunistic pathogen Ashrafi, Roghaieh (University of Jyväskylä, 2017)
Effect of resource availability on evolution of virulence and competition in an environmentally transmitted pathogen Pulkkinen, Katja; Pekkala, Nina; Ashrafi, Roghaieh; Hämäläinen, Dorrit M.; Nkembeng, Aloysius N.; Lipponen, Anssi; Hiltunen, Teppo; Valkonen, Janne; Taskinen, Jouni (Federation of European Microbiological Societies; Oxford University Press, 2018)Understanding ecological and epidemiological factors driving pathogen evolution in contemporary time scales is a major challenge in modern health management. Pathogens that replicate outside the hosts are subject to selection ...
The influence of infective dose, nutrient availability and coinfection on virulence of Flavobacterium columnare : implications of intensive aquaculture on opportunistic infections Kinnula, Hanna (University of Jyväskylä, 2016)Ecological factors are known to affect disease dynamics and even lead to disease emergence. Especially in opportunistic, environmentally transmitted pathogens, the environment may significantly contribute to pathogen ...
Broad thermal tolerance is negatively correlated with virulence in an opportunistic bacterial pathogen Ashrafi, Roghaieh; Bruneaux, Matthieu; Sundberg, Lotta-Riina; Pulkkinen, Katja; Valkonen, Janne; Ketola, Tarmo (Wiley-Blackwell Publishing, Inc., 2018)Predicting the effects of global increase in temperatures on disease virulence is challenging, especially for environmental opportunistic bacteria, because pathogen fitness may be differentially affected by temperature ...
Does the freshwater mussel Anodonta anatina remove the fish pathogen Flavobacterium columnare from water? Hajisafarali, Mahsa; Aaltonen, Sari; Pulkkinen, Katja; Taskinen, Jouni (Springer, 2021)Global decline of freshwater mussels (Unionoida) is threatening biodiversity and the essential ecosystem services that mussels provide. As filter-feeding organisms, freshwater mussels remove phytoplankton and suspended ...