My research

I’m fascinated by the vast diversity of microbes on Earth (and beyond?), and all of the important things they do in the environment (a lot of which we still really don’t understand). I’m especially interested in questions involving photosynthesis.

I use culture-based and cell-free techniques to experimentally investigate microbial physiology; analytical and imaging techniques to examine chemistries, textures, and spatial relationships in both petrographic and biological samples; and I do both geological and ecological fieldwork.

 

CURRENT PROJECTS


PHOTOSYNTHESIS  &  MANGANESE

The element manganese played a key role in the evolution of oxygenic photosynthesis, arguably the most important turning point in the history of life on Earth. To better understand this role, I am deciphering the vestiges of ancient manganese-cycling ecosystems recorded in sedimentary rocks and examining the physiology of manganese oxidation by modern Cyanobacteria. I am also investigating broader connections between photosynthesis and manganese in the environment. This work is the core of my PhD thesis research with Woody Fischer.

MnStrom

Lingappa, et al., 2019

Featured on NASA astrobiology portal


MICROBIAL MATS

Little Ambergris Cay, a tiny uninhabited island in the Turks and Caicos, hosts a tidal lagoon environment dominated by microbial mats. These mats are built by Cyanobacteria but host a complex community of other microorganisms, and they resemble fossilized microbial structures that dominated the ancient biosphere. My work is primarily on the microbial diversity and interactions within the mat communities, but I am also involved in efforts to characterize the geochemistry and carbonate sedimentology on Little Ambergris. A major goal of this work is to study how this ecosystem recovers from Hurricane Irma and responds to environmental changes like rising sea level.



PAST PROJECTS


RABIES BIOCHEMISTRY

At Prosetta Biosciences, I helped develop a cell-free protein synthesis system for the translation and assembly of rabies viral capsid proteins. Using this system, I elucidated a pathway of capsid formation and established a screen for novel anti-viral drugs that interfered with this pathway. I worked on rabies drug development for several small molecules that came out of this screen, and I characterized host multiprotein complexes and protein-protein interactions involved in rhabdovirus capsid assembly.

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Lingappa, et al., 2013

Featured in Cell Leading Edge


ALGAE AND OUTER SPACE

At NASA Ames Research Center, I studied oxidative stress responses in the green algae Chlamydomonas reinhardtii and Volvox carteri. I looked at changes in intracellular reactive oxygen species, metal ion transport, antioxidant enzyme activity, and photosynthetic efficiency, to better understand stress response networks in these organisms which represent the bookends of a model lineage for the evolution of multicellularity. This work also had applications for space biology, and I was involved in biocompatibility work for the development of biological payloads to fly in Earth orbit.


MARS ANALOG MICROBES1b2.1e

My undergraduate research at Hampshire College involved studying microbial diversity and physiology in rock varnish from the Mojave and Atacama deserts, specifically looking at UV resistant isolates as an analog for potential microorganisms in varnish on Mars. I also brought this work to the Mars Desert Research Station as part of a simulated mission to Mars.


STAR CLUSTER ASTROPHYSICS

As a research assistant at the Cerro Tololo Inter-American Observatory, I studied the globular cluster NGC2808. I measured the radial velocity dispersion of the cluster, and split the populations of stars by elemental anti-correlations looking for different spatial distributions and/or kinematics.

479px-NGC_2808_HST
HST image of NGC2808