Projects Course 2017

Sharebiota – Interspecies Communication through Microbiota

by Yuxi Liu, Alejandra Grandon and Kirsty Millar


In biology the close and prolonged interactions between living beings are known as symbiosis, which, in the past, was restricted for relations where both organisms benefit from the interaction but has a broader meaning now. Multispecies study, a field that tries to understand life on earth as one entirely connected system that has coevolved together, multiplying and spreading beyond their own physical form, is now emerging. Yet there is an invisible form of symbiosis that happens around our body and other living things – the symbiosis with microbes, the oldest and tiniest life form on earth, which we need for every basic function in our body. Our research has shown an interesting symbiotic association happening between humans, microbes, and dogs. Specifically, the sharing of dog microbiota is beneficial for humans.


We want to enhance the exchange of microbiota and bring the benefits to more people, especially those who don’t have a chance to live with dogs. What if we can build a microbiota station to introduce dog microbiota to the public in a fun and elegant way?

Microbio Bank

Microbio Bank is a public installation that acts as a bank and station for the communication between dogs and humans. It is an integration of collection, production, and distribution of dog microbiota. It consists of 3 parts. The bottom part acts as a dog playground, which can collect skin microbes from dogs. People can also drop in dog stool in the middle part, where the production for microbiota samples happens. After the whole process, the microbiota bubbles will be released from the trumpet in the top part.

The production process involves different steps, from sampling, dilution, colonies, purify, to quality check, fermentation, centrifugation, freeze drying and integration. Every time when people drop in dog stool, the machine will be triggered to release bubbles that contain beneficial dog microbiota, which can be screened, assessed, and selected through the evolution process.

Probiotic Product

We also envision a topical probiotic product made from the microbiota selected through the process above. By applying it to hands, for instance, people can benefit, as well as transfer the beneficial microbiota through petting the dog.


The term microbiome was first coined in the online publication ‘The Scientist’ by Joshua Lederberg in 2001 as ‘the ecological community of commensal, symbiotic, and pathogenic microorganisms that literally share our body space’, but specifying the definition of the human microbiome has been complicated by confusion about terminology. The human microbiota consists of the 10-100 trillion microbial cells harboured by each person, which are primarily bacteria in the gut. Whereas the human microbiome consists of the genes these cells harbour. Despite the extensive demonisation that has ensued in an age of antibiotics and antimicrobials, the microbes living in and on our bodies are largely commensal and provide us with genetic variation and gene functions that human cells have not needed to evolve on their own. The microbiota constitutes a massive 90% of the total number of cells associated with our bodies with only the remaining 10% being human cells. Microbial communities colonise not only the gut but also the oral cavity, skin, and faeces.

It has been known for many years that gut microbiota gives specific function in host nutrient metabolism, drug metabolism, maintenance of structural integrity of the gut mucosal barrier, immunomodulation, and protection against pathogens as confirmed by scientists in an article last year in the World Journal of Gastroenterology. A number of articles in the media have also implicated the gut microbiota as having a role in brain function and mood.

An article in the New York Times noted that gut microbiota create a profound number of chemicals, and researchers like Mark Lyte from Texas Tech University have found that among those chemicals are the same substances used by our neurons to communicate and regulate mood; for example, dopamine, serotonin and gamma-aminobutyric acid (GABA). These,in turn, appear to play a function in intestinal disorders, which can coincide with depression, anxiety, autism and other disorders.

The skin is the human body’s largest organ and like the gut, it is colonised by a diverse range of microorganisms. However, unlike the gut microbiota which are generally well characterised, the role of microbes on the skin surface has not been well studied. A review in the British Journal of Dermatology reported that like the gut microbiota, the skin microbiota can influence the host immune system and certain species, such as Staphylococcus epidermidis may provide protection against certain common pathogens.

An article in the media highlighted that humans and their pet dogs share so much of the same microbiota that dogs could be described as probiotics for their owners. Additionally, research has showed that Western children who are raised with animals, particularly dogs, show less autoimmune disorders than children raised without animals. This relationship is not one sided though; it is mutualistic. However, the benefits for dogs have remained largely unexplored as research remains human-centric. We are therefore exploring the theme of interspecies communication between humans and their pets through the skin microbiota to benefit both the human and the pet.

Research carried out in the journal eLife demonstrated that dog ownership significantly increases the shared skin microbiota in cohabiting adults, and dog-owning adults shared more skin microbiota with their own dogs than with other dogs. Research carried out at the at the University of Colorado Boulder in 2013 showed that married couples share more microbiota with their dog than with each other.