Journal of Microbiology

, Volume 51, Issue 5, pp 639–643 | Cite as

Experimental phasing using zinc and sulfur anomalous signals measured at the zinc absorption peak

  • Sangmin Lee
  • Min-Kyu Kim
  • Chang-Jun Ji
  • Jin-Won LeeEmail author
  • Sun-Shin ChaEmail author
Microbial Physiology and Biochemistry


Iron is an essential transition metal required for bacterial growth and survival. Excess free iron can lead to the generation of reactive oxygen species that can cause severe damage to cellular functions. Cells have developed iron-sensing regulators to maintain iron homeostasis at the transcription level. The ferric uptake regulator (Fur) is an iron-responsive regulator that controls the expression of genes involved in iron homeostasis, bacterial virulence, stress resistance, and redox metabolism. Here, we report the expression, purification, crystallization, and phasing of the apo-form of Bacillus subtilis Fur (BsFur) in the absence of regulatory metal ions. Crystals were obtained by microbatch crystallization method at 295 K and diffraction data at a resolution of 2.6 Å was collected at the zinc peak wavelength (λ=1.2823 Å). Experimental phasing identified the positions of one zinc atom and four sulfur atoms of cysteine residues coordinating the zinc atom, indicating that the data contained a meaningful anomalous scattering originating from the ordered zinc-coordinating sulfur atoms, in spite of the small anomalous signals of sulfur atoms at the examined wavelength.


Ferric uptake regulator transcription regulator crystallization experimental phasing 


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Copyright information

© The Microbiological Society of Korea and Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.Marine Biotechnology Research DivisionKorea Institute of Ocean Science and TechnologyAnsanRepublic of Korea
  2. 2.Ocean Science and Technology SchoolKorea Maritime UniversityPusanRepublic of Korea
  3. 3.Department of Life Science and Institute for Natural SciencesHanyang UniversitySeoulRepublic of Korea
  4. 4.Department of Marine BiotechnologyUniversity of Science and TechnologyDaejeonRepublic of Korea

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