I was recently awarded with a 2-year postdoctoral fellowship from Lundbeckfonden.
This awarded project will investigate the heterogeneity of O2 and pH landscapes in and between biofilm aggregates to elucidate interactions between the chemical microenvironment and growth rates of pathogenic bacteria. The project will also unravel if interactions between bacterial strains influence the chemical microenvironment and how such community synergies affect growth characteristics of pathogens.
From Sønderholm et al (2017) doi:10.1128/AEM.00113-17
Chronic biofilm infections lead to persistent inflammatory defense mechanisms, as biofilms are much more tolerant to antibiotics than planktonic bacteria due to factors such as slow growth rates. Dominant biofilm species P. aeruginosa and S. aureus have highly flexible metabolisms and their growth characteristics are thus determined by the availability of substrate. However, high-resolution information about substrate availability around biofilm aggregates is largely unknown due to constraints in current methodologies.
In this project we will use a novel combination of high temporal and spatial resolution measurements of the chemical microenvironment using optical nano-particle sensors with high-resolution measurements of bacterial growth-rates using a quantitative PNA-FISH based method. Nano-particle sensors will be incorporated into a new in vitro biofilm-model together with bacteria, which will allow imaging of both growth-rates and the chemical microenvironment during biofilm formation.
The project is carried out at the Department of Immunology and Microbiology (Faculty of Health Science, University of Copenhagen) in the lab of Thomas Bjarnsholt. The project will be supported by important collaboration with a leading research group in optical sensor chemistry headed by Professor Michael Kühl at the Department of Biology, University of Copenhagen.
hot springs (Nagano Prefecture, Japan), to study the diversity, ecology, and activity of microbial mats at the hot-springs in collaboration with Asc. Professor Vera Thiel and colleagues at the Photosynthetic Microbial Consortia Laboratory, TMU, Japan. To disclose the microbial community activity and ecology, a comprehensive 36-hour sampling experiment was conducted at a cyanobacterial dominated hot spring microbial mat at 58C in Nakabusa hot springs. As part of this field experiment data was collected for genomics (DNA), metatranscriptomic (RNA) and metabolomic analysis
(metabolites), as well as relevant physicochemical parameters, such as light, temperature, oxygen, pH and sulfide. So far very little is known about the diel activity of the microbial mat community members at Nakabusa and this study will lead to a comprehensive understanding of the community and their function.
Reef Symposium held in Honolulu, Hawaii. Here I presented work from my PhD on how light gradients in coral tissues shape the light acclimation status of its endosymbionts found in different positions within the coral host. The work was presented in the session “Acclimatization and adaptation in reef organisms”.
biologists and engineers all working in the area of biophotonics. On the poster I presented 3 different projects from my PhD dealing with microscale interactions in stratified photosynthetic systems. In densely pigmented systems, such as biofilms, corals and macroalgae, pronounced gradients of light and chemical parameters important for photosynthesis can exist on very small scales (<1 mm). The poster presents 3 different mechanisms that serves to counteract these sub-optimal conditions. The poster can be accessed 
speciation. Micro heterogeneities were found in both O2 and pH environment and greater oxidation capabilities were found in light exposure of the leaf canopy and during elevated temperatures.
for publication in the journal Frontiers in Microbiology – Microbial Symbiosis. This data was collected on Heron Island on the Southern Great Barrier Reef and describes how algae living deep inside coral tissue is not experiencing photosynthetic saturation, in high light, in contrast to algae living closer to the tissue surface. The data was collected using a range of microsensor techniques which allowed us to measure photosynthetic efficiencies of the symbiotic algae inside living coral tissue for the first time. The conclusions of this study could have important implications for our understanding of symbiont resilience against high light stress.
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