Virginia Tech
Investigating Hfq-dependent Small Regulatory RNA, Bsr34, and Its Roles in Brucella abortus Physiology and Pathogenicity
Abstract
dc:description.abstractBrucellosis, a debilitating zoonotic disease caused by the facultative intracellular pathogen Brucella, relies on rapid gene regulation for survival within host cells. Small regulatory RNAs (sRNAs), often chaperoned by Hfq, are key post-transcriptional regulators of bacterial virulence and stress adaptation, yet remain largely uncharacterized in Brucella. Following the identification of Hfq-associated sRNA candidates in B. suis, this study provides the first functional characterization of Bsr34, an Hfq-dependent sRNA in B. abortus 2308. We confirmed that Bsr34 expression is entirely Hfq-dependent. Phenotypic analysis of a Δbsr34 mutant revealed no defects in in vitro growth or general stress survival but showed significant attenuation in a murine infection model, indicating a specific role in virulence. While an initial chloramphenicol sensitivity phenotype was inconsistent, expression profiling demonstrated that Bsr34 is specifically downregulated under envelope stress (polymyxin B) and acidic pH, but not under oxidative or nutrient stress. Collectively, these findings establish Bsr34 as a bona fide Hfq dependent sRNA involved in host-specific adaptation and stress response, laying the groundwork for future studies to identify its regulatory targets and elucidate its precise role in Brucella pathogenesis.
Degree
thesis:*- Name thesis:degree_name
- Master of Science
- Level thesis:degree_level
- masters
- Discipline thesis:degree_discipline
- Biomedical and Veterinary Sciences
- Department dc:contributor.department
- Biomedical and Veterinary Sciences
- Grantor dc:publisher
- Virginia Tech
- Year dc:date.issued
- 2026
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Saeed, Tahaa
- Chair dc:contributor.committeechair
-
- Caswell, Clayton Christopher
- Committee members dc:contributor.committeemember
-
- Allen, Irving Coy
- Gloag, Erin Samantha
- Wang, Xiaogang
Subjects
dc:subject × 7Rights
dc:rights- Statement dc:rights
-
- In Copyright
- Licence dc:rights.uri
- Language dc:language.iso
- en
Identifiers
dc:identifier.*- Dc Identifier Other
- vt_gsexam:45645
- OAI identifier oai:identifier
- oai:vtechworks.lib.vt.edu:10919/140924