Sponsor
Portland State University. Department of Biology
First Advisor
Anna-Louise Reysenbach
Date of Publication
Summer 12-13-2013
Document Type
Thesis
Degree Name
Master of Science (M.S.) in Biology
Department
Biology
Language
English
Subjects
Hydrothermal vent animals -- Research -- Italy -- Vulcano Island, Hydrothermal vent ecology -- Research -- Italy -- Vulcano Island, Marine microbiology – Research -- Italy -- Vulcano Island
DOI
10.15760/etd.1485
Physical Description
1 online resource (vii, 59 pages)
Abstract
As part of a large study aimed at searching for patterns of diversity in the genus Persephonella along the north to south geochemical gradient of the ELSC, ten novel strains of Alphaproteobacteria were isolated unexpectedly. Using defined media under microaerophilic conditions to enrich for Persephonella from chimney samples collected at the seven vent fields on the ELSC and the dilution to extinction by serial dilution method to purify cultures, a total of ten strains belonging to the Alphaproteobacteria were isolated. Two of these isolates, designate MN-5 and TC-2 were chosen for further characterization and are proposed as two new species of a novel genus to be namedThermopetrobacter. Both strains are aerobic, capable of chemoautotrophic growth on hydrogen and grow best at 55°C, pH 6 and 3.0% NaCl. Strain MN-5 is capable of heterotrophic growth on pyruvate and malate and TC-2 is only able to grow heterotrophically with pyruvate. The GC content of MN-5 is 69.1 and TC-2 is 67 mol%. GenBank BLAST results from the 16S rRNA gene reveal the most closely related sequence to MN-5 is 90% similar and the most closely related sequence to strain TC-2 is 89% similar.
Sampling at a shallow marine vent on the coast of Vulcano Island, Italy in 2007 led to the isolation of a novel species of Hydrogenothermus, a genus within the Hydrogenothermaceae family. This isolate, designated NV1, represents the secondHydrogenothermusisolated from a shallow marine vent. NV1 cells are rod-shaped, approximately 1.5μm long and 0.7μm wide, motile by means of a polar flagellum and grow singularly or in short chains. Cells grow chemoautotrophically using hydrogen or thiosulfate as electron donors and oxygen as the sole electron acceptor. Growth was observed between 45 and 75°C with an optimum of 65°C (doubling time 140 min), pH 4.0-6.5 and requires NaCl (0.5-6.0% w/v). The G+C content of total DNA is 32 mol%.
Rights
In Copyright. URI: http://rightsstatements.org/vocab/InC/1.0/ This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).
Persistent Identifier
http://archives.pdx.edu/ds/psu/10363
Recommended Citation
Sislak, Christine Demko, "Novel Thermophilic Bacteria Isolated from Marine Hydrothermal Vents" (2013). Dissertations and Theses. Paper 1486.
https://doi.org/10.15760/etd.1485