Structure of a fatty acid-binding protein from Bacillus subtilis determined by sulfur-SAD phasing using in-house chromium radiation

Research output: Contribution to journalJournal articleResearchpeer-review

  • Jie Nan
  • Yanfeng Zhou
  • Cheng Yang
  • Erik Brostromer
  • Ole Kristensen
  • Xiao-Dong Su
Sulfur single-wavelength anomalous dispersion (S-SAD) and halide-soaking methods are increasingly being used for ab initio phasing. With the introduction of in-house Cr X-ray sources, these methods benefit from the enhanced anomalous scattering of S and halide atoms, respectively. Here, these methods were combined to determine the crystal structure of BsDegV, a DegV protein-family member from Bacillus subtilis. The protein was cocrystallized with bromide and low-redundancy data were collected to 2.5 A resolution using Cr Kalpha radiation. 17 heavy-atom sites (ten sulfurs and seven bromides) were located using standard methods. The anomalous scattering of some of the BsDegV S atoms and Br atoms was weak, thus neither sulfurs nor bromides could be used alone for structure determination using the collected data. When all 17 heavy-atom sites were used for SAD phasing, an easily interpretable electron-density map was obtained after density modification. The model of BsDegV was built automatically and a palmitate was found tightly bound in the active site. Sequence alignment and comparisons with other known DegV structures provided further insight into the specificity of fatty-acid selection and recognition within this protein family.
Original languageEnglish
JournalActa Crystallographica. Section D: Biological Crystallography
Issue number5
Pages (from-to)440-448
Publication statusPublished - 2009

Bibliographical note

Keywords: Amino Acid Sequence; Bacillus subtilis; Bacterial Proteins; Binding Sites; Bromides; Chromium; Crystallography, X-Ray; Models, Molecular; Molecular Sequence Data; Palmitates; Protein Conformation; Recombinant Fusion Proteins; Sequence Alignment; Sequence Homology, Amino Acid; Sulfur

ID: 12843360