Host Microbiome (Holobiont) Interactions

All higher organisms live in intimate association with microbes. The interactions are primarily positive or neutral, with microbes imparting protection from pathogens or providing nutrients to the hosts, which in turn provide favourable niches for residing biofilms. However, microbes are also the causative agents of disease in a host and, as biofilms, are responsible for acute and chronic infections.

SCELSE’s host microbiome (holobiont) interactions research covers several host organisms, from plants and invertebrates in aquatic and terrestrial systems to humans, to understand the broad scope of interactions, and complex associations between hosts and their microbiomes. This knowledge provides insights into the healthy functioning and wellbeing of the host organisms, with broader implications for ecosystem health. The response of an organism to competition and environmental change involves both the host as well as its microbiome. As such, holobiont systems can be manipulated to promote resilience, such as increased tolerance of temperature stress in corals, or modifying gut or skin microbiomes for host health and pathogen deterrence. Other systems being interrogated are seagrass, crop plants, mammals, and insects.

Insect-associated microbiomes

The microbial communities associated with insect hosts are investigated with respect to both biological and mechanical vectors by dissecting the microbiomes of mosquitos and flies. As insects are major agents of infectious diseases, they often inhabit densely populated areas where their propagation is increased. Although national vector control agencies focus on the surveillance of biological vectors, the mechanical vectors themselves are largely understudied.

Human-associated microbiomes

SCELSE’s human-associated microbiome studies include biofilms connected with cardiovascular disease, organs such as the skin, the eye and gastro-intestinal tract, as well as microbial biofilm communities implicated in cancer.

Cardiovascular disease is the leading cause of death worldwide and atherosclerosis is a chronic inflammatory disease. Increasing evidence indicates that infections and chronic inflammatory diseases are linked with increased risk of atherosclerosis. Similarly, bacteria have been implicated in cancer progression and although the concept is in its infancy, investigating the potential role of biofilms in tumorigenesis may have implications for cancer prevention.

Although microorganisms are widely prevalent, each part of the body (system or organ) plays a distinct role and therefore requires a particular combination of bacteria for optimal function. E. coli in our intestines aid the breakdown of food and the production of essential vitamins; its presence in the urinary tract, however, gives rise to bladder and urethra infections. Disruptions to the delicate balance of microorganisms can impact negatively on health. Some bacterial species also perform diverse roles and are able to inhabit various parts of the body and adaptively respond to the environment as needed. Understanding our microbiome as a whole and as component parts – the gut, eye, and skin microbiomes  – is therefore imperative.

Plant-associated microbiomes

SCELSE's plant-associated microbiome studies investigate how microbial communities or “microbiomes” and their life on interfaces of solid, liquid or air as “biofilms” drive the processes occurring in natural environments such as surface freshwater or plant surfaces. Members of these species share resources such as metabolites or metabolic signals and they have diverse interactions with their hosts and immediate environments, all based on ecological principles. A multidisciplinary approach incorporates hydrology, meta-genomics, metabolomics, computational, and high-resolution imaging to study these interesting biological systems.

In the media:

Future of Farming – Microbiome Solutions for Green Environment

Urban farm microbiome sustainable crop production

Microorganisms that help veggies grow