Home Publications CV

This is a non-comprehensive overview of recent and ongoing research projects to which I have contributed.

16S rRNA gene primer comparison in an ecological context

I tested four 16S rRNA gene primer sets on both mock communities of known composition and time-series
samples from the Santa Barbara Channel. Unsurprisingly, we found that all primer sets had strengths and
weaknesses and that the most recently developed primer sets were overall the best choices. However,
we also found that ecological conclusions (e.g., depth and temporal patterns, and correlations with
environmental parameters) were largely unaffected by primer choice. This suggests that, while the field needs
to be cautious when comparing relative abundances produced by different primers, it is valid to compare
broader ecological findings - an important point as primer sets fall in and out of favor over time.

Resulting publication

Microbial community characterization in the Clarion-Clipperton Zone

I took part in the DeepCCZ cruise to the Clarion-Clipperton Zone in summer 2018. This cruise aimed
to characterize the biodiversity present in manganese nodule fields prior to potential mining activity in
the region. I was part of the team sampling microbial communities on manganese nodules and in the
sediments and water column. These samples will be analyzed for both 16S and 18S rRNA marker genes
and functional genes from metagenomics.

Dissolved organic matter bioavailability across an eddy gradient

In spring 2018, I participated in a SCOPE cruise that transited from a cyclonic eddy to an anti-cyclonic
eddy located to the north of Hawai`i. To test the hypothesis that bacterioplankton communities in different
eddy types would be pre-conditioned to respond differently to variable DOM, I set up experimental bioassays
to measure DOM remineralization along the gradient from eddy center to eddy center. I tested both in situ
DOM and lysates from cultures of Prochlorococcus and a coccolithophore. Very preliminary results show
variable dissolved organic nitrogen remineralization between lysate sources.