Meet 2023 Young Microbiologist of the Year finalist: Thomas Heaven

Posted on September 28, 2023   by Microbiology Society

The Sir Howard Dalton Young Microbiologist of the Year Prize is awarded by the Society each year. The prize recognises and rewards excellence in science communication by a Microbiology Society member who is a postgraduate student or postdoctoral researcher, having gained their PhD in the last two years. In the lead up to the final, taking place on 3 October 2023, we will be getting to know each of the finalists in this blog series.


Thomas Heaven (University of Lincoln, UK)

Thomas Heaven  blog image
© Thomas Heaven

What are your current research interests?
I am interested in the evolutionary arms race between plants and microbes. In particular, how the close relationships between different species of plants and biotrophic plant pathogens has driven adaptations in both host and parasite. My PhD research focuses on powdery mildews (Erysiphaceae), a family of obligate biotrophic fungi. To survive, powdery mildew species must suppress the immune system of their host plants, I investigated the genes behind this suppression in powdery mildew species affecting horticultural crops in the UK. 

What is the theme of your talk?
Many dicot powdery mildew fungi display a broad host range. However, this is not the case for either Podosphaera aphanis or Podosphaera leucotricha, the powdery mildew species infecting strawberry and apple. I was interested in the host adaptation of these species. Powdery mildew host range is determined by effector proteins. Powdery mildew effectorome size has previously been associated with lineage and host range. Through assembly of local pangenomes and in silico gene annotation I have discovered expansion of effector protein families in P. leucotricha, describing an 'effectorome' more than four times larger than that of closely related P. aphanis

How would you explain your research to a GCSE student?

Just as there are diseases that affect humans and other animals, there are diseases that affect plants. There is interest in understanding these plant diseases better, as many can damage the crops grown by farmers. My research is on the microbial fungi that cause 'powdery mildew' disease in apple, raspberry and strawberry plants. Powdery mildew species are parasitic and grow in living plant tissue, absorbing nutrients from their host. In order to maintain this close relationship with a living host, powdery mildew fungi must suppress their host plant's immune system. I have been investigating genes called 'effectors', which are responsible for this immune suppression. An arms race exists between plants and plant pathogens, where pathogens evolve new effector genes and plants evolve new resistance genes to counter them. Which effector genes a particular species of powdery mildew has determines which species of plant it can infect. I am interested in how effector genes have evolved in different species of mildew. Is there a core set of effectors every powdery mildew species has? How do different effectors cause immune suppression? Why can some species of powdery mildew infect many types of plant, whilst others can only infect one host species? 

If you weren’t a microbiologist, what would you be?

One of those people that camps out on the side of a Himalayan Mountain for 6 months so that they can get one photo of a snow leopard for David Attenborough, orr maybe an astronaut.

Why is it important for you to be a member of the Microbiology Society?
Membership of the Microbiology Society allows me to stay up to date with developments in the field of microbiology. Conferences, workshops, webinars, and publications provide exposure to ideas that I can apply in my own research and the opportunity to network with potential collaborators.