Isolation of Treponema pallidum from Wild Chimpanzees and Gorillas

Description
Treponemal disease in primates is caused by the spirochaete bacteria Treponema pallidum. Three subspecies of T. pallidum are currently recognized; pallidum, pertenue, and endemicum. In humans, these are generally associated with the diseases syphilis, yaws, and bejel, respectively. Syphilis is

Treponemal disease in primates is caused by the spirochaete bacteria Treponema pallidum. Three subspecies of T. pallidum are currently recognized; pallidum, pertenue, and endemicum. In humans, these are generally associated with the diseases syphilis, yaws, and bejel, respectively. Syphilis is located worldwide and spreads through sexual contact, while yaws and bejel are geographically limited and spread by skin-to-skin contact. Despite different clinical presentations, these subspecies are very similar genetically and are unable to be serologically distinguished. Reports of symptoms resembling treponemal disease in non-human primates (NHPs) date to the 1960s, though few studies have been executed to isolate and study T. pallidum from NHPs on a molecular level. Obtaining whole-genome sequences of T. pallidum from a variety of NHPs will help efforts to determine evolutionary relationships of strains within and between species. Currently, no whole-genome sequences of T. pallidum have been sequenced from chimpanzees or gorillas. In this thesis, I will determine if T. pallidum is detectable in fecal samples from NHP’s with visible signs of treponemal infection using a polymerase chain reaction (PCR) method.
Date Created
2024-05
Agent

Novel DNA Extraction Methods for Mollusks and the History and Significance of Bermuda Land Snails

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Description

Bermuda Land Snails make up a genus called Poecilozonites that is endemic to Bermuda and is extensively present in its fossil record. These snails were also integral to the creation of the theory of punctuated equilibrium. The DNA of mollusks

Bermuda Land Snails make up a genus called Poecilozonites that is endemic to Bermuda and is extensively present in its fossil record. These snails were also integral to the creation of the theory of punctuated equilibrium. The DNA of mollusks is difficult to sequence because of a class of proteins called mucopolysaccharides that are present in high concentrations in mollusk tissue, and are not removed with standard DNA extraction methods. They inhibit Polymerase Chain Reactions (PCRs) and interfere with Next Generation Sequencing methods. This paper will discuss the DNA extraction methods that were designed to remove the inhibitory proteins that were tested on another gastropod species (Pomacea canaliculata). These were chosen because they are invasive and while they are not pulmonates, they are similar enough to Bermuda Land Snails to reliably test extraction methods. The methods that were tested included two commercially available kits: the Qiagen Blood and Tissue Kit and the Omega Biotek Mollusc Extraction Kit, and one Hexadecyltrimethylammonium Bromide (CTAB) Extraction method that was modified for use on mollusk tissue. The Blood and Tissue kit produced some DNA, the mollusk kit produced almost none, and the CTAB Extraction Method produced the highest concentrations on average, and may prove to be the most viable option for future extractions. PCRs attempted with the extracted DNA have all failed, though it is likely due to an issue with reagents. Further spectrographic analysis of the DNA from the test extractions has shown that they were successful at removing mucopolysaccharides. When the protocol is optimized, it will be used to extract DNA from the tissue from six individuals from each of the two extant species of Bermuda Land Snails. This DNA will be used in several experiments involving Next Generation Sequencing, with the goal of assembling a variety of genome data. These data will then be used to a construct reference genome for Bermuda Land Snails. The genomes generated by this project will be used in population genetic analyses between individuals of the same species, and between individuals of different species. These analyses will then be used to aid in conservation efforts for the species.

Date Created
2021-05
Agent