Few secondary metabolites have been
reported from mammalian microbiome
bacteria despite the large numbers of diverse taxa that inhabit warm-blooded
higher vertebrates. As a means to investigate natural products from
these microorganisms, an opportunistic sampling protocol was developed,
which focused on exploring bacteria isolated from roadkill mammals.
This initiative was made possible through the establishment of a newly
created discovery pipeline, which couples laser ablation electrospray
ionization mass spectrometry (LAESIMS) with bioassay testing, to target
biologically active metabolites from microbiome-associated bacteria.
To illustrate this process, this report focuses on samples obtained
from the ear of a roadkill opossum (Dideiphis virginiana) as the source of two bacterial isolates (Pseudomonas sp. and Serratia sp.) that produced several new
and known cyclic lipodepsipeptides (viscosin and serrawettins, respectively).
These natural products inhibited biofilm formation by the human pathogenic
yeast Candida albicans at concentrations well below
those required to inhibit yeast viability. Phylogenetic analysis of
16S rRNA gene sequence libraries revealed the presence of diverse
microbial communities associated with different sites throughout the
opossum carcass. A putative biosynthetic pathway responsible for the
production of the new serrawettin analogues was identified by sequencing
the genome of the Serratia sp. isolate. This study
provides a functional roadmap to carrying out the systematic investigation
of the genomic, microbiological, and chemical parameters related to
the production of natural products made by bacteria associated with
non-anthropoidal mammalian microbiomes. Discoveries emerging from
these studies are anticipated to provide a working framework for efforts
aimed at augmenting microbiomes to deliver beneficial natural products
to a host.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.