Cloning, purification, crystallization and preliminary X-ray analysis of ESX-1-secreted protein regulator (EspR) from Mycobacterium tuberculosis

Shanti P. Gangwar, Sita R. Meena, Ajay K. Saxena

Research output: Contribution to journalArticle

2 Scopus citations


ESX-1-secreted protein regulator (EspR; Rv3849) is a key regulator in Mycobacterium tuberculosis that delivers bacterial proteins into the host cell during infection. EspR binds directly to the Rv3616c-Rv3614c promoter and activates transcription and secretes itself from the bacterial cell by the ESX-1 system. The three-dimensional structure of EspR will aid in understanding the mechanisms by which it binds to the Rv3616c-Rv3614c promoter and is involved in transcriptional activation. This study will significantly aid in the development of EspR-based therapeutics against M. tuberculosis. The full-length EspR gene from M. tuberculosis (H37Rv strain) was cloned and overexpressed as a soluble protein in Escherichia coli. The protein was purified by affinity chromatography using His-tagged protein followed by size-exclusion chromatography. EspR was crystallized using polyethylene glycol 3350 as precipitant. The crystals diffracted to 3.2 Å resolution using synchrotron radiation of wavelength 0.97625 Å. The crystal belonged to space group P3121 and contained three monomers in the asymmetric unit. Native and heavy-atom-derivatized data sets were collected from EspR crystals for use in ab initio structure-solution techniques.

Original languageEnglish (US)
Pages (from-to)83-86
Number of pages4
JournalActa Crystallographica Section F: Structural Biology and Crystallization Communications
Issue number1
StatePublished - Jan 1 2011



  • ESX-1-secreted protein regulator
  • Mycobacterium tuberculosis
  • Rv3849

ASJC Scopus subject areas

  • Biophysics
  • Structural Biology
  • Biochemistry
  • Genetics
  • Condensed Matter Physics

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