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Patterns and regulation of ribosomal RNA transcription in Borrelia burgdorferi.

Bugrysheva JV, Godfrey HP, Schwartz I, Cabello FC - BMC Microbiol. (2011)

Bottom Line: DNA per cell was higher in cells in exponential as compared to stationary phase at either temperature; protein per cell was similar at both temperatures in both phases.Interestingly, a rel Bbu deletion mutant unable to generate (p)ppGpp did not down-regulate rRNA at transition to stationary phase in serum-containing BSK-H at 34°C, similar to the relaxed phenotype of E. coli relA mutants.We conclude that rRNA transcription in B. burgdorferi is complex and regulated both by growth phase and by the stringent response but not by temperature-modulated growth rate.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Microbiology and Immunology, Basic Science Building, New York Medical College, Valhalla, NY 10595, USA.

ABSTRACT

Background: Borrelia burgdorferi contains one 16S and two tandem sets of 23S-5S ribosomal (r) RNA genes whose patterns of transcription and regulation are unknown but are likely to be critical for survival and persistence in its hosts.

Results: RT-PCR of B. burgdorferi N40 and B31 revealed three rRNA region transcripts: 16S rRNA-alanine transfer RNA (tRNA Ala); tRNA Ile; and both sets of 23S-5S rRNA. At 34°C, there were no differences in growth rate or in accumulation of total protein, DNA and RNA in B31 cultured in Barbour-Stoenner-Kelly (BSK)-H whether rabbit serum was present or not. At 23°C, B31 grew more slowly in serum-containing BSK-H than at 34°C. DNA per cell was higher in cells in exponential as compared to stationary phase at either temperature; protein per cell was similar at both temperatures in both phases. Similar amounts of rRNA were produced in exponential phase at both temperatures, and rRNA was down-regulated in stationary phase at either temperature. Interestingly, a rel Bbu deletion mutant unable to generate (p)ppGpp did not down-regulate rRNA at transition to stationary phase in serum-containing BSK-H at 34°C, similar to the relaxed phenotype of E. coli relA mutants.

Conclusions: We conclude that rRNA transcription in B. burgdorferi is complex and regulated both by growth phase and by the stringent response but not by temperature-modulated growth rate.

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Related in: MedlinePlus

Detection of (p)ppGpp in B. burgdorferi B31 grown at 34°C in BSK-H in the presence (lane 1) or absence (lane 2) of 6% rabbit serum, or in BSK-H at 23°C in the presence of 6% rabbit serum (lane 3). Similar amounts of (p)ppGpp were detected in cells under all three culture conditions.
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Figure 4: Detection of (p)ppGpp in B. burgdorferi B31 grown at 34°C in BSK-H in the presence (lane 1) or absence (lane 2) of 6% rabbit serum, or in BSK-H at 23°C in the presence of 6% rabbit serum (lane 3). Similar amounts of (p)ppGpp were detected in cells under all three culture conditions.

Mentions: At 34°C, the growth rate of B. burgdorferi and synthesis of total DNA, RNA and protein were unaffected by the presence or absence of rabbit serum as spirochetes grew from 3 × 104 to 3 × 108 cells/ml (Figure 3). Levels of RNA and protein per cell in B. burgdorferi were similar to those in slow-growing E. coli [8], while the level of DNA per cell was similar to that of normally dividing E. coli [8]. At 23°C, there was a lag in increases in B. burgdorferi cell numbers and total DNA, RNA and protein; in addition growth rate was slower, final concentrations of cells were three times lower (Figure 3A), as were total DNA, RNA and protein relative to those at 34°C (Figure 3B-D). These differences did not appear to be due to triggering of the stringent response by these environmental variations, since similar amounts of (p)ppGpp were detected in B. burgdorferi B31 grown in BSK-H in the presence or absence of rabbit serum at 34°C or in the presence of rabbit serum at 23°C (Figure 4). These results indicate that the absence of rabbit serum in BSK-H did not trigger slow growth at 34°C or changes in (p)ppGpp levels at either temperature.


Patterns and regulation of ribosomal RNA transcription in Borrelia burgdorferi.

Bugrysheva JV, Godfrey HP, Schwartz I, Cabello FC - BMC Microbiol. (2011)

Detection of (p)ppGpp in B. burgdorferi B31 grown at 34°C in BSK-H in the presence (lane 1) or absence (lane 2) of 6% rabbit serum, or in BSK-H at 23°C in the presence of 6% rabbit serum (lane 3). Similar amounts of (p)ppGpp were detected in cells under all three culture conditions.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3037291&req=5

Figure 4: Detection of (p)ppGpp in B. burgdorferi B31 grown at 34°C in BSK-H in the presence (lane 1) or absence (lane 2) of 6% rabbit serum, or in BSK-H at 23°C in the presence of 6% rabbit serum (lane 3). Similar amounts of (p)ppGpp were detected in cells under all three culture conditions.
Mentions: At 34°C, the growth rate of B. burgdorferi and synthesis of total DNA, RNA and protein were unaffected by the presence or absence of rabbit serum as spirochetes grew from 3 × 104 to 3 × 108 cells/ml (Figure 3). Levels of RNA and protein per cell in B. burgdorferi were similar to those in slow-growing E. coli [8], while the level of DNA per cell was similar to that of normally dividing E. coli [8]. At 23°C, there was a lag in increases in B. burgdorferi cell numbers and total DNA, RNA and protein; in addition growth rate was slower, final concentrations of cells were three times lower (Figure 3A), as were total DNA, RNA and protein relative to those at 34°C (Figure 3B-D). These differences did not appear to be due to triggering of the stringent response by these environmental variations, since similar amounts of (p)ppGpp were detected in B. burgdorferi B31 grown in BSK-H in the presence or absence of rabbit serum at 34°C or in the presence of rabbit serum at 23°C (Figure 4). These results indicate that the absence of rabbit serum in BSK-H did not trigger slow growth at 34°C or changes in (p)ppGpp levels at either temperature.

Bottom Line: DNA per cell was higher in cells in exponential as compared to stationary phase at either temperature; protein per cell was similar at both temperatures in both phases.Interestingly, a rel Bbu deletion mutant unable to generate (p)ppGpp did not down-regulate rRNA at transition to stationary phase in serum-containing BSK-H at 34°C, similar to the relaxed phenotype of E. coli relA mutants.We conclude that rRNA transcription in B. burgdorferi is complex and regulated both by growth phase and by the stringent response but not by temperature-modulated growth rate.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Microbiology and Immunology, Basic Science Building, New York Medical College, Valhalla, NY 10595, USA.

ABSTRACT

Background: Borrelia burgdorferi contains one 16S and two tandem sets of 23S-5S ribosomal (r) RNA genes whose patterns of transcription and regulation are unknown but are likely to be critical for survival and persistence in its hosts.

Results: RT-PCR of B. burgdorferi N40 and B31 revealed three rRNA region transcripts: 16S rRNA-alanine transfer RNA (tRNA Ala); tRNA Ile; and both sets of 23S-5S rRNA. At 34°C, there were no differences in growth rate or in accumulation of total protein, DNA and RNA in B31 cultured in Barbour-Stoenner-Kelly (BSK)-H whether rabbit serum was present or not. At 23°C, B31 grew more slowly in serum-containing BSK-H than at 34°C. DNA per cell was higher in cells in exponential as compared to stationary phase at either temperature; protein per cell was similar at both temperatures in both phases. Similar amounts of rRNA were produced in exponential phase at both temperatures, and rRNA was down-regulated in stationary phase at either temperature. Interestingly, a rel Bbu deletion mutant unable to generate (p)ppGpp did not down-regulate rRNA at transition to stationary phase in serum-containing BSK-H at 34°C, similar to the relaxed phenotype of E. coli relA mutants.

Conclusions: We conclude that rRNA transcription in B. burgdorferi is complex and regulated both by growth phase and by the stringent response but not by temperature-modulated growth rate.

Show MeSH
Related in: MedlinePlus