In this photo illustration, the Scripps Institution of Oceanography pier is shown with images generated using imaging mass spectrometry set between piling. One of the molecules identified in metabolic exchange by the study is illustrated along the upper course of the pier.
the merest of microbes must be able to talk, to be able to interact
with its environment and with others to not just survive, but to thrive.
This cellular chatter comes in the form of signaling molecules and
exchanged metabolites (molecules involved in the process of metabolism
or living) that can have effects far larger than the organism itself.
Humans, for example, rely upon thousands of products derived from
microbially produced molecules, everything from antibiotics and food
supplements to ingredients used in toothpaste and paint.
most of what’s known about how microbes communicate with each other is
the result of indirect observation and measurements. There has been no
general or informative technique for observing the manifold metabolic
exchange and signaling interactions between microbes, their hosts and
environments. Until now. In a paper published in the May 5 online issue
of the journal Angewandte Chemie,
researchers at UC San Diego and Scripps Institution of Oceanography
report using a new form of imaging mass spectrometry to dramatically
visualize multiplex microbial interactions.
able to better see and understand the metabolic interplay between
microbial communities and their surrounding biology means we can better
detect and characterize the molecules involved and perhaps discover new
and better therapeutic and commercially viable compounds,” said Pieter
C. Dorrestein, PhD, associate professor at the UCSD Skaggs School of
Pharmacy and Pharmaceutical Sciences and the paper’s senior author.
and colleagues used matrix-assisted laser desorption ionization (MALDI)
mass spectrometry, a relatively new approach that creates
two-dimensional, spatial images of microbes and biomolecules (proteins,
peptides, sugars) too fragile to withstand other mass spectrometry
their first subject, the scientists collected marine microbial
assemblages scraped off the slimy surfaces of a barnacle attached to the
Scripps Pier. The resulting images, produced after careful preparation,
offered new revelations.
of the things we see that we haven’t with other techniques is that the
dialog between microbes is multiplexed,” said Dorrestein. “There are
many conversations going on at the same time, many changes happening at
the same time. We see competition for resources such as iron, but also
that microbes secrete molecules that alter the phenotypes (sets of
observable characteristics) of neighboring organisms.”
said the ability to better visualize the vastly complex world of
microbial communication is changing the ways scientists investigate how
two or more microbes are studied and eventually engineered.
than enumerating which microbes are present, as in many metagenomic
efforts, our current approach is anticipated to address the why, when
and how questions of microbial interactions instead of just the who,”
of the paper are Yu-Liang Yang, Yuquan Xu, Michael J. Meehan, Bradley
S. Moore, Nuno Bandeira, UCSD Skaggs School of Pharmacy and
Pharmaceutical Sciences; Roland Kersten, Center for Marine Biotechnology
and Biomedicine, Scripps Institution of Oceanography, UCSD; Wei-Ting
Liu, UCSD Department of Chemistry and Biochemistry.
Funding for this research was provided, in part, by the National Institutes of Health and the Beckman Foundation.