Defense Date
12-1-2020
Document Type
Thesis
Degree Type
Master of Science
Degree Name
Marine Science
First Advisor
Jose Lopez, Ph.D.
Second Advisor
Hidetoshi Urakawa, Ph.D.
Third Advisor
Robert Smith, Ph.D.
Keywords
Cinachyrella spp., sulfur cycle, symbionts, 16S rRNA, sulfur-reducing/oxidizing bacteria
Abstract
Symbionts within marine sponges are actively participating in the biogeochemical cycles. Among them, the role of symbiont microbes in the sulfur cycle remains a mystery. This study measured the abundance of microbes within the genus Cinachyrella before and after exposure to hydrogen sulfide. A four-part study was conducted: a) five-hour drop experiments, b) vertical distribution experiments, c) five-hour uptake experiments, and d) long-term exposure experiments. The five-hour drop experiment utilized a microsensor to measure sulfide levels, which was lowered 1.0 mm every thirty minutes for a total of 5 hours. Three trials were performed, each with one sponge and a control with no sponge. The vertical distribution experiments measured hydrogen sulfide levels throughout 9.0 mm. A five-hour uptake experiment measured hydrogen sulfide over five hours without the use of microsensors. The bacterial composition was detailed during long-term exposure experiments, where three sponges were exposed to 60 μmol/L for several weeks. Tissue samples collected from the long-term exposure experiment underwent microbial DNA extractions and high-throughput sequencing. Hydrogen sulfide concentrations from the five-hour drop, vertical-distribution, and five-hour experiments underwent various generalized additive models and generalized linear models. A significant relationship between time (depth for the vertical-distribution) and hydrogen sulfide concentration (p-valueDraconibacterium, family Rhodobacteraceae, and genus Halodesulfovibrio within sponges. These data suggest that Cinachyrella spp. can filter and process hydrogen sulfide from the water column with help from its microbiome.
NSUWorks Citation
Shelby K. Cain. 2020. Investigation of Sulfur Cycling in Marine Sponge Cinachyrella Spp. from a South Florida Reef. Master's thesis. Nova Southeastern University. Retrieved from NSUWorks, . (28)
https://nsuworks.nova.edu/hcas_etd_all/28.
Included in
Bioinformatics Commons, Computational Biology Commons, Environmental Microbiology and Microbial Ecology Commons, Marine Biology Commons, Other Animal Sciences Commons