Characterization of Antibiotic Resistance in <i>Vibrio cholerae</i> Isolated From Ships' Ballast and Other Environmental Sources

<p>Ships' ballast has been implicated as a vector in the dispersal of invasive species into new environments. Numerous cases have been documented for the introduction of macroorganisms via ballasting operations, but what is less known is the role of ballast water and residuals in the spread of potentially harmful microbes, especially with reference to novel genotypes. Of particular interest are the genes encoding for various forms of antibiotic resistance, many of which are carried on mobile genetic elements. A four-year sampling effort has yielded over 300 putative isolates of <em>Vibrio cholerae</em> from ships' ballast tanks and various environmental sources, of which 208 have been profiled for antibiotic susceptibility using twelve diverse antibiotics. The results demonstrate widespread resistance to β-lactam antibiotics (67%), especially in nearshore isolates as compared to those isolates derived from ships' ballast tanks. Plasmid extractions and restriction enzyme analyses have shown evidence of plasmids of approximately 38 and 23 kbp in many of these isolates, suggesting the potential for horizontal gene transfer (HGT). Additional work using restriction fragment length polymorphisms and PCR for specific antibiotic resistance genes has yet to reveal the genetic source of the observed antibiotic resistance. Knowledge from this study and future microcosm experiments will help to ascertain the potential for HGT in a ballast tank setting.</p>

Name thesis:degree_name

Doctor of Philosophy (PhD)

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Ocean & Earth Sciences

Year dc:date.available

2009

Author dc:creator

• Thomson, Frank Kornegay, III

Contributors dc:contributor

• Fred C. Dobbs
• Wayne L. Hynes
• Alexander Bochdansky

• Antibiotic resistance
• Ballast water
• Horizontal gene transfer
• Invasive species
• Plasmids
• Microbiology
• Molecular Biology
• Oceanography

Statement dc:rights

• <p>In Copyright. URI: <a href="http://rightsstatements.org/vocab/InC/1.0/">http://rightsstatements.org/vocab/InC/1.0/</a> 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).</p>

Identifier

9781109142877

OAI identifier oai:identifier

oai:digitalcommons.odu.edu:oeas_etds-1078