Help Privacy Policy Disclaimer
  Advanced SearchBrowse




Journal Article

Crystal Structure of IlvC, a Ketol-Acid Reductoisomerase, from Streptococcus Pneumoniae


Shin,  Donghyuk
Departments of Biological Sciences, Sungkyunkwan University, Suwon, Korea ;
Max Planck Fellow Group ER remodelling Group, Prof. Ivan Đikić, Max Planck Institute of Biophysics, Max Planck Society;

External Resource
No external resources are shared
Fulltext (restricted access)
There are currently no full texts shared for your IP range.
Fulltext (public)
There are no public fulltexts stored in PuRe
Supplementary Material (public)
There is no public supplementary material available

Kim, G., Shin, D., Lee, S., Yun, J., & Lee, S. (2019). Crystal Structure of IlvC, a Ketol-Acid Reductoisomerase, from Streptococcus Pneumoniae. Crystals, 9(11): 551. doi:10.3390/cryst9110551.

Cite as: https://hdl.handle.net/21.11116/0000-0005-6A88-B
Biosynthesis of branched-chain amino acids (BCAAs), including isoleucine, leucine and valine, is required for survival and virulence of a bacterial pathogen such as Streptococcus pneumoniae. IlvC, a ketol-acid reductoisomerase (E.C. with NADP(H) and Mg2+ as cofactors from the pathogenic Streptococcus pneumoniae (SpIlvC), catalyzes the second step in the BCAA biosynthetic pathway. To elucidate the structural basis for the IlvC-mediated reaction, we determined the crystal structure of SpIlvC at 1.69 Å resolution. The crystal structure of SpIlvC contains an asymmetric dimer in which one subunit is in apo-form and the other in NADP(H) and Mg2+-bound form. Crystallographic analysis combined with an activity assay and small-angle X-ray scattering suggested that SpIlvC retains dimeric arrangement in solution and that D83 in the NADP(H) binding site and E195 in the Mg2+ binding site are the most critical in the catalytic activity of SpIlvC. Crystal structures of SpIlvC mutants (R49E, D83G, D191G and E195S) revealed local conformational changes only in the NADP(H) binding site. Taken together, our results establish the molecular mechanism for understanding functions of SpIlvC in pneumococcal growth and virulence.