Do fungi hold the key to healthy fatty-acid metabolism? Insights from MALDI-ToF-MS analysis of human gut fungi and their metabolites.

Project Code: 10385912

Faculty: Liggins Institute

Department: Liggins Institute

Main Supervisor: Dr Elizabeth McKenzie (emck002)

Application open date: 31 Aug 2017

Application deadline: 02 Mar 2018

Enrolment information: NZ Citizens, NZ Permanent Residents, International

Introduction

The human gut teems with a vast ecosystem of bacteria, fungi, viruses, archaea and invertebrates – the gut microbiome. Current research is focused on bacteria, yet symbiotic fungi – the  mycobiome – represents a significant biomass that potentially plays a critical role in nutrition and immunity. The few studies that exist on gut fungi reveal striking differences between healthy and obese individuals. Faecal metabolite profiling of individuals predisposed to diabetes and obesity also showed altered methylketones, fatty acids and elevated levels of butyrolactone - a microbial signalling compound. Methylketones are metabolites produced by fungally mediated fatty acid metabolism in cultured foods like cheese. However, this process has not yet been demonstrated in humans.

Using radioisotope labelling and Matrix Assisted Laser Desorption Ionisation Time of Flight Imaging Mass Spectrometry, this multidisciplinary study will identify gut fungi and their metabolites, and will shed light on how  they  are  distributed  in  faeces  and  what  fungal  structures  produce  metabolites. This could reveal  a  major  microbially  mediated  pathway  for  metabolism  of  fatty  acids in humans. Understanding the role of the mycobiome in the gut can help uncover the processes  leading  to  metabolic  dysregulation,  which  will  aid  the  development  of  treatment interventions and preventive measures.

What we are looking for in a successful applicant

B+ average or better in final year of undergraduate degree.

Some experience with analytical/biochemistry/organic chemistry desirable.

OK working with human faeces.

Enjoys writing

Self-motivated

Curious, creative thinker

Conscientious, attention to detail

Objective

1. Develop  a  method  for  real-time  visualisation  of  faecal fungi and their metabolites   using 
MALDI-ToF-MS;
2. Identify  faecal  fungi  and  their  metabolites  using  mass  spectrometry  and  obtain  images  of  fungi and their metabolites in both faeces and faecal cultures; 
3. Isolate fungal  cultures  from  faeces  and  use  isotopic  labelling  of  nutrients  to  investigate
origin of methylketones;
4. Determine the  effect  of γ-butyrolactone on growth  habit  and/or  ratios  of  fatty  acids  to  methylketones.

Other information

This Project is funded by an FRDF grant and starts as soon as a suitable candidate is found.