Project description:Comparative proteomics analysis to evaluate the influence of varying culture conditions on a planktonic freshwater dwelling bacterium, Polynucleobacter asymbioticus that belongs to the class Gammaproteobacteria. In the present study, a type strain Polynucleobacter asymbioticus strain QLW-P1DMWA-1T (= DSM 18221 = CIP 10981) was cultured in triplicates in sterile UV-permeable polyethylene bags (~35% permeability; Whirl-Pak®, Nasco). Culturing was carried out at 4°C, 26°C and 26° C plus 30 minutes of ultraviolet radiation exposure two times a day using 100W ARIMED® B UV lamps (Cosmedico®, Germany). We have applied mass spectrometry based large-scale screening of proteins to investigate to better understanding of the survival nature of this microbe.
Project description:Polynucleobacter asymbioticus strain QLW-P1DMWA-1T represents a group of highly successful heterotrophic planktonic bacteria, dwelling in freshwater systems (lakes, ponds, and streams) across all climatic zones and across all continents. This includes habitats characterised by strongly fluctuating environmental conditions. So the experiments were designed to mimick winter and summer scenarios with additional impact of UV irradiation. Comparative transcriptomic studies were conducted to analyse gene-expression levels in contrasting experimental conditions. Overall, molecular candidates were revealed that may contribute in rapid acclimatisation of this strain in their immediate environment.
Project description:Columnaris disease is a prevalent disease in freshwater environments worldwide caused by the ubiquitous aquatic bacterium Flavobacterium species. Adhesion to the external mucosal surfaces of fishes is the initial stage of infection, and the gills specifically have been identified as both a primary target and release site for this pathogen. Previous research has indicated that a predominant US aquaculture product, the hybrid striped bass (Morone chrysops x M. saxatilis), is more susceptible to infection with Flavobacterium columnare (covae) than the maternal white bass (M. chrysops) parental species. Therefore, to further elucidate the differences between these fish we conducted a transcriptomic profiling study examining the differences of gene expression in gill mucosal tissue over time after exposure to F. covae isolate LSU-066-04. Combined with previous work, these data provide a greater understanding of host immune response to a common pathogen in moronids.