Laser Ablation Mass Spectrometric Analysis of the Gross Composition of Unusual Filaments Tethering Desiccation Tolerant Algae to Substrates
EMSL Project ID
50437
Abstract
Microscopic green algae inhabiting desert microbiotic crusts are remarkably diverse phylogenetically, and many desert lineages have independently evolved from aquatic ancestors. We have been working with five related desert and aquatic species within the family Scenedesmaceae to begin examining mechanisms underlying desiccation tolerance. One of the algae derived from desert microbiotic crust -- Acutodesmus deserticola – is shaped like a lemon and extrudes filaments from its poles as it grows. The filaments are extruded by the daughter cells after they are released from the mother cell wall following division, and the filaments can get stuck to the substrate. As the filaments continue to grow, the cell bodies themselves can then be propelled around the substrate by the growing filaments. We have observed this for cells growing in PDMS microfluidic devices. We are very interested in these desiccation tolerant algae because of these filaments, which John Oakey (our engineering collaborator) views as a possible way to tether algae to substrates in bioreactors. We need to know what these filaments are. We tested them using a battery of stains and with polarized light microscopy, and both cellulose and proteins are implicated. Because these cells are approximately 5 micrometers in size, and the filaments are approximately 1 micrometers wide and between 5 and 30 micrometers long, we contacted Liz Alexander about the possibility of using laser ablation mass spectrometry to analyze the general classes of compounds in filaments vs. cell walls. She encouraged us to submit a rapid access proposal for work to begin Sept. 3, 2018. If the laser ablation approach works, we expect that the mass spectra will indicate a signature of protein in data from ablated filaments that otherwise would not be present in cellulosic, hemi-cellulosic, and pectin-containing cell walls. We expect the empty mother cell walls will be predominantly carbohydrate-based -- cellulose, hemi-cellulose, and pectin. The initial rapid access work we propose would serve as proof of principle. If the laser ablation approach does work, then a larger project proposal could be developed to connect the laser ablation setup with a different mass spectrometer that provides more detailed insight into the chemical nature of the filaments. This project may provide a good stepping stone for developing the laser ablation mass spectrometry in a new direction prioritizing compound identification over the speed and extensive spatial mapping currently the focus of the laser ablation approach.
Project Details
Project type
Limited Scope
Start Date
2018-09-03
End Date
2018-11-03
Status
Closed
Released Data Link
Team
Principal Investigator