Microbial Hydrocarbon Cycling — Coal Oil Point

Overview

This project tests the link between biogenic hydrocarbon cycling and the microbial response to petroleum at Coal Oil Point. We incubate coastal seawater with liposome+alkane (to mimic phytoplankton production), liposome+petroleum, and substrate-only treatments, then track community shifts with archaeal-inclusive 16S amplicons and MGII-targeted qPCR.1 Fieldwork and analyses are led in the Valentine Lab (UCSB).2

Quick Facts

  • Role: Researcher, Valentine Lab (UCSB)
  • When: Jan 2023 – Aug 2025
  • Skills: small-boat sampling, incubations, DNA extraction, 16S rRNA (archaea-inclusive), qPCR (MGII), bioinformatics (DADA2/QIIME-style), figure design
  • Motivation: Do MGII archaea consume biogenic alkanes and are they inhibited by petroleum exposure?3

Background and Questions

  • Does the short-term, phytoplankton-derived alkane cycle help “prime” microbial communities that can act as biofilters when oil enters the system?
  • Which treatments (liposome+alkane vs. liposome+petroleum) increase MGII abundance and shift overall community composition?4

Methods

  • Step 1 — Sample collection: coastal seawater near Coal Oil Point; summer emphasis when MGII often increase in the SBC.
  • Step 2 — Incubations (~72 h): liposome+alkane, liposome+petroleum, alkane-only, petroleum-only; in-situ temp/light.
  • Step 3 — Analysis: DNA extraction → 16S rRNA amplicons (archaea-inclusive primers) → community profiles; qPCR with MGII-specific primers → absolute/relative abundance. Sequencing via AVITI at UC Davis Core; bioinformatics with DADA2 and related tools.5

Results (preview)

Data collection and analysis are ongoing. Early goals focus on quality-controlled 16S profiles, MGII qPCR calibration, and treatment comparisons; figures will be added here as they finalize.

Outputs

  • Poster / slides (coming soon)
  • Manuscript (planned)

Acknowledgements

Valentine Lab (UCSB), Dr. David Valentine, Dr. Eleanor Arrington; thanks to campus small-boat program and Coastal Fund.

Footnotes

  1. Project summary, methods, and motivation from the Coastal Fund proposal (liposome treatments; 16S with archaeal-inclusive primers; MGII qPCR; AVITI sequencing).↩︎

  2. Project overview slides: Microbial Hydrocarbon Cycling at Coal Oil Point (Valentine Lab).↩︎

  3. Project summary, methods, and motivation from the Coastal Fund proposal (liposome treatments; 16S with archaeal-inclusive primers; MGII qPCR; AVITI sequencing).↩︎

  4. Project summary, methods, and motivation from the Coastal Fund proposal (liposome treatments; 16S with archaeal-inclusive primers; MGII qPCR; AVITI sequencing).↩︎

  5. Project summary, methods, and motivation from the Coastal Fund proposal (liposome treatments; 16S with archaeal-inclusive primers; MGII qPCR; AVITI sequencing).↩︎