English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Borrelia burgdorferi , the spirochetal agent of Lyme disease, is a vector-borne pathogen that cycles between a mammalian host and tick vector. This complex life cycle requires that the spirochete modulate its gene expression program to facilitate growth and maintenance in these diverse milieus.  B. burgdorferi  contains an operon that is predicted to encode proteins that would mediate the uptake and conversion of glycerol to dihydroxyacetone phosphate. Previous studies indicated that expression of the operon is elevated at 23°C and is repressed in the presence of the alternative sigma factor RpoS, suggesting that glycerol utilization may play an important role during the tick phase. This possibility was further explored in the current study by expression analysis and mutagenesis of  glpD , a gene predicted to encode glycerol 3-phosphate dehydrogenase. Transcript levels for  glpD  were significantly lower in mouse joints relative to their levels in ticks. Expression of GlpD protein was repressed in an RpoS-dependent manner during growth of spirochetes within dialysis membrane chambers implanted in rat peritoneal cavities. In medium supplemented with glycerol as the principal carbohydrate, wild-type  B. burgdorferi  grew to a significantly higher cell density than  glpD  mutant spirochetes during growth in vitro at 25°C.  glpD  mutant spirochetes were fully infectious in mice by either needle or tick inoculation. In contrast,  glpD  mutants grew to significantly lower densities than wild-type  B. burgdorferi  in nymphal ticks and displayed a replication defect in feeding nymphs. The findings suggest that  B. burgdorferi  undergoes a switch in carbohydrate utilization during the mammal to tick transition. Further, the results demonstrate that the ability to utilize glycerol as a carbohydrate source for glycolysis during the tick phase of the infectious cycle is critical for maximal  B. burgdorferi  fitness.

Borrelia burgdorferi Requires Glycerol for Maximum Fitness During The Tick Phase of the Enzootic Cycle