Role of vapBC toxin-antitoxin loci in the thermal stress response of Sulfolobus solfataricus

Charlotte R. Cooper, Amanda J. Daugherty, Sabrina Tachdjian, Paul H. Blum, Robert M. Kelly

Research output: Contribution to journalArticlepeer-review

45 Scopus citations


TA (toxin-antitoxin) loci are ubiquitous in prokaryotic micro-organisms, including archaea, yet their physiological function is largely unknown. For example, preliminary reports have suggested that TA loci are microbial stress-response elements, although it was recently shown that knocking out all known chromosomally located TA loci in Escherichia coli did not have an impact on survival under certain types of stress. The hyperthermophilic crenarchaeon Sulfolobus solfataricus encodes at least 26 vapBC (where vap is virulence associated protein) family TA loci in its genome. VapCs are PIN (PilT N-terminus) domain proteins with putative ribonuclease activity, while VapBs are proteolytically labile proteins, which purportedly function to silence VapCs when associated as a cognate pair. Global transcriptional analysis of S. solfataricus heat-shock-response dynamics (temperature shift from 80 to 90°C) revealed that several vapBC genes were triggered by the thermal shift, suggesting a role in heat-shock-response. Indeed, knocking out a specific vapBC locus in S. solfataricus substantially changed the transcriptome and, in one case, rendered the crenarchaeon heat-shock-labile. These findings indicate that more work needs to be done to determine the role of VapBCs in S. solfataricus and other thermophilic archaea, especially with respect to post-transcriptional regulation.

Original languageEnglish (US)
Pages (from-to)123-126
Number of pages4
JournalBiochemical Society Transactions
Issue number1
StatePublished - 2009
Externally publishedYes


  • Archaeon
  • Heat shock
  • Hyperthermophile
  • Stress response
  • Sulfolobus solfataricus
  • Toxin-antitoxin locus

ASJC Scopus subject areas

  • Biochemistry


Dive into the research topics of 'Role of vapBC toxin-antitoxin loci in the thermal stress response of Sulfolobus solfataricus'. Together they form a unique fingerprint.

Cite this