Related Experiment Video
Updated: Jun 13, 2026
10:37
Cultivation Methods of Spirochetes from Borrelia burgdorferi Sensu Lato Complex and Relapsing Fever Borrelia
Published on: November 25, 2022
Does RecA have a role in Borrelia recurrentis?
S J Cutler1, I J Rinky, E M Bonilla
1School of Health & Bioscience, University of East London, London, UK. s.cutler@uel.ac.uk
Summary
Genomic sequencing revealed a truncated recA gene in Borrelia recurrentis, the cause of louse-borne relapsing fever, but not in Borrelia duttonii. This finding distinguishes these related spirochaetes.
Area of Science:
- Microbiology
- Genomics
- Bacteriology
Background:
- RecA protein is crucial for bacterial DNA repair and recombination.
- Genomic analysis of relapsing fever spirochaetes, Borrelia recurrentis and Borrelia duttonii, revealed differences in the recA gene.
- Investigating recA gene variations is important for understanding bacterial pathogenesis and evolution.
Purpose of the Study:
- To investigate the significance of recA gene truncation in Borrelia recurrentis compared to Borrelia duttonii.
- To determine if the observed recA truncation in B. recurrentis is a genuine characteristic or an artifact of in vitro cultivation.
- To identify genetic markers for differentiating between B. recurrentis and B. duttonii.
Main Methods:
- Direct sequencing of the recA gene from clinical samples of patients with relapsing fever.
- Comparative genomic analysis of Borrelia species.
- Identification of specific polymorphisms within the recA gene.
Main Results:
- Confirmed a premature stop codon (truncation) in the recA gene of Borrelia recurrentis from seven louse-borne relapsing fever patient samples.
- Absence of recA truncation was confirmed in three tick-borne relapsing fever (Borrelia duttonii) patient samples.
- Identified unique signature polymorphisms enabling differentiation between B. recurrentis and B. duttonii.
Conclusions:
- The truncation of the recA gene is a characteristic feature of Borrelia recurrentis, not an in vitro artifact.
- RecA gene variation plays a role in distinguishing between these closely related Borrelia species.
- The identified polymorphisms offer a reliable method for differentiating louse-borne and tick-borne relapsing fever spirochaetes.
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