Download MendeleyCrystal structure of SPSB2 in complex with a rational designed RGD-containing cyclic peptide inhibitor of SPSB2-iNOS interaction.
You, T., Wang, Y., Li, K., Zhang, D., Wei, H., Luo, Y., Li, H., Lu, Y., Su, X., Kuang, Z.(2017) Biochem Biophys Res Commun 489: 346-352
- PubMed: 28549582 Search on PubMed
- DOI: https://doi.org/10.1016/j.bbrc.2017.05.122
- Primary Citation Related Structures:
5XN3 - PubMed Abstract:
SPRY domain-containing SOCS box protein 2 (SPSB2) is a negative regulator of inducible nitric oxide synthase (iNOS) that modulates the lifetime of iNOS and thus the levels of nitric oxide (NO) production. Inhibitors that can disrupt the endogenous SPSB2-iNOS interaction and augment NO production have potential as novel antimicrobial and anticancer drugs. In this study, we have designed a cyclic peptide (cR8), containing an RGD motif and the SPSB2 binding motif (DINNNV). ITC and chemical shift perturbation showed that cR8 binds to the iNOS binding site on SPSB2 with a K d of 671 nM, and saturation transfer difference NMR showed that cR8 binds to α v β 3 integrin-expressing cells. Moreover, we determined the crystal structure of SPSB2 in complex with cR8, at a resolution of 1.34 Å. cR8 forms extensive hydrogen bonding with SPSB2 residues, but loss of an intramolecular hydrogen bond that is present in SPSB2-bound iNOS peptide may destabilize the bound conformation of cR8 and lead to a gentle reduction in SPSB2 binding affinity. These results serve as a useful basis for designing site-directed SPSB2 inhibitors in the future.
- Department of Cell Biology and Institute of Biomedicine, Jinan University, Guangzhou 510632, China; Guangdong Provincial Key Laboratory of Bioengineering Medicine, National Engineering Research Center of Genetic Medicine, Guangzhou 510632, China.
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