Community interactions

It is becoming increasingly clear that microbes have fundamental impacts on human and environmental health. Human-associated microbes not only cause infectious diseases, but also perform a multitude of functions important for human well-being, including disease suppression, aid with food digestion, and priming of the immune system. In addition, early-life exposure to microbes in the built and natural environment is also implicated to be dictating the development of many immune-related diseases, such as asthma.

Most of these microbial processes are dictated or influenced by interactions – either between the microbes and their host, or between the microbes themselves. While tremendous progress has recently been made towards deciphering these interaction networks, much still remains poorly understood or entirely uninvestigated. For example, interactions between microbes are believed to be one of the main drivers of the accelerating antibiotic resistance crisis, allowing bacteria to share resistance genes with each other, even across species barriers. There is also a growing recognition that antibiotics can influence bacteria in ways that enhance their virulence, which in turn can worsen human disease outcomes, but this process remains mostly uninvestigated. Finally, perturbations to the human microbiome have been identified to be associated with, contributing towards, or perhaps even solely causative of many human diseases, including colon cancer, depression, IBS and IBD.

We want to identify the factors that provide functional stability in microbial communities, i.e., how a consortium of microorganisms can coexist and maintain a stable relationship with each other and their host, and how that stability contributes to avoiding intrusion or uncontrolled growth by detrimental microbes such as pathogens. While the specific mechanisms that cause dysbiosis are unknown, microbial biodiversity seems to play an important role in maintaining a healthy microbiota. At the same time, very little is known about which genes that contribute to whether a community can withstand environmental disturbances or invasion events. Species interactions are a fundamental part of plant and animal ecology, which means that there exists a large theoretical framework for interactions between species, individuals and their environment, and our research aims to apply this framework to the human microbiome to better understand what influences its stability.

Open questions of interest

  • What are the effects of disturbances such as antibiotic exposure on interactions in microbial communities?
  • Which genes are important for community resilience to environmental changes?
  • Are the genetic determinants that are fundamental for microbial interactions different when the community is exposed to multiple stressors at once?

Key publications

  • Burman E, Bengtsson-Palme J: Microbial community interactions are sensitive to small differences in temperature. Frontiers in Microbiology, 12, 672910 (2021). doi: 10.3389/fmicb.2021.672910 [Paper link]
  • Bengtsson-Palme J: Microbial model communities: To understand complexity, harness the power of simplicity. Computational and Structural Biotechnology Journal, 18, 3987-4001 (2020). doi: 10.1016/j.csbj.2020.11.043 [Paper link]
  • Bahram M, Hildebrand F, Forslund SK, Anderson JL, Soudzilovskaia NA, Bodegom PM, Bengtsson-Palme J, Anslan S, Coelho LP, Harend H, Huerta-Cepas J, Medema MH, Maltz MR, Mundra S, Olsson PA, Pent M, Põlme S, Sunagawa S, Ryberg M, Tedersoo L, Bork P: Structure and function of the global topsoil microbiome. Nature, 560, 7717, 233–237 (2018). doi: 10.1038/s41586-018-0386-6 [Paper link]
  • Forsell J, Bengtsson-Palme J, Angelin M, Johansson A, Evengård B, Granlund M: The relation between Blastocystis and the intestinal microbiota in Swedish travellers. BMC Microbiology, 17, 231 (2017). doi: 10.1186/s12866-017-1139-7 [Paper link]
  • Thorell K, Bengtsson-Palme J, Liu OH, Gonzales RVP, Nookaew I, Rabeneck L, Paszat L, Graham DY, Nielsen J, Lundin SB, Sjöling Å: In vivo analysis of the viable microbiota and Helicobacter pylori transcriptome in gastric infection and early stages of carcinogenesis. Infection and Immunity, 85, 10, e00031-17 (2017). doi: 10.1128/IAI.00031-17 [Paper link]