The rising frequency of drug-resistant bacterial infections pose an imminent threat to human health.
Attempts to generate novel antibiotics to address this problem often fail because the outer membrane (OM) of
gram-negative bacteria acts as a barrier that blocks the entry of many small molecules. This OM barrier is
densely packed with lipopolysaccharides (LPS) and outer membrane proteins (OMPs) that organize
heterogeneously within the OM. Specifically, it has been demonstrated that OMPs form higher-order assemblies
in the membrane termed “islands”. The OM porins are trimeric and highly abundant OMPs but it is unknown how
this oligomerization state influences their function, insertion into the OM, or the assembly of OMP islands. I
hypothesize that OMP trimerization is critical for OMP function and fundamentally underlies the heterogenous
organization of the OM. Using the model OMP, LamB, I have developed a set of tools that will allow me to
examine this hypothesis. First, I will use bacterial genetic techniques to determine how OMP oligomeric state
influences OMP function and partitioning of LPS. Second, I will use fluorescence microscopy techniques to
characterize the role of OMP oligomerization in the OMP island assembly. Finally, I will determine how local
secretion of OMPs affect OM organization. Together, my proposed work will define the molecular mechanisms
that govern the organization of the OM. Importantly, this will inform strategies for disrupting the OM and in
designing OM permeable antibiotics.
The training goal of this fellowship is to continue to grow my scientific knowledge while further developing
skills as a leader and mentor in order to fulfill my career goal of becoming a research group leader. Being a
member of the Silhavy lab at Princeton University will allow me to develop a teaching philosophy and participate
in the teaching and mentoring of undergraduate and graduate students. I will perfect my communication skills
through ample opportunities to present my work at meetings and conferences. Additionally, the Molecular Biology
Department at Princeton University is collaborative, interdisciplinary environment that promotes that
development of ideas and sharing of expertise. Together, I believe that the completion of this training plan in the
research environment of the Silhavy lab at Princeton University will allow me to develop the necessary skills to
run my own research group.