Microbial co-cultivation has emerged as a promising approach to unravel interspecies
communication at the molecular scale. Nonetheless, a significant hurdle in this research
domain is highlighting the microbial origin of metabolites present in co-culture systems.
Metabolites observed in co-cultures can be absent in their respective single cultures,
rendering it impossible to determine the microorganisms responsible for their production.
For non-volatile metabolites, imaging mass spectrometry can help address this challenge
by localising the induced molecules within the co-cultivation sample. However, for
volatile induced metabolites, this issue persists as an unresolved challenge that
requires further investigation and development of appropriate methodologies. To address
this challenge, a three head-to-head microbial co- culture strategy was devised, focusing
on the investigation of volatile interactions through gas chromatography-mass spectrometry
(GC-MS). This methodology was used to study the volatile molecular interactions among
three microbial species: Fusarium culmorum, Aspergillus amstelodami and Cladosporium cladosporioides. The employed strategy enabled the detection of induced volatile molecules (terpenes)
as well as the identification of the microorganism producing these metabolites. Additionally,
the induced molecules underwent antimicrobial activity assessment to gain deeper insight
into their potential contribution to the microbial interplay. These results illustrate
that the developed three head-to-head microbial co-culture strategy can be employed
to better investigate the inter-microbial molecular cross-talk and efficiently uncover
metabolite induction specific to individual microorganisms.
