title: Probing the equilibrium unfolding of ketosteroid isomerase through xenon-perturbed 1H-15N multidimensional NMR spectroscopy.
abstract: We used xenon-perturbed 1H-15N multidimensional NMR to investigate the structural changes in the urea-induced equilibrium unfolding of the dimeric ketosteroid isomerase (KSI) from Pseudomonas putida biotype B. Three limited regions located on the beta3-, beta5- and beta6-strands of dimeric interface were significantly perturbed by urea in the early stage of KSI unfolding, which could lead to dissociation of the dimer into structured monomers at higher denaturant concentration as the interactions in these regions are weakened. The results indicate that the use of xenon as an indirect probe for multidimensional NMR can be a useful method for the equilibrium unfolding study of protein at residue level.
authors.affiliation: Department of Chemistry, Pohang University of Science and Technology, Pohang, 790-784, Republic of Korea.
authors.forename: Hyeong Ju
authors.initials: HJ
authors.lastname: Lee
authors.forename: Hye Seon
authors.initials: HS
authors.lastname: Moon
authors.forename: Do Soo
authors.initials: DS
authors.lastname: Jang
authors.forename: Hyung Jin
authors.initials: HJ
authors.lastname: Cha
authors.forename: Bee Hak
authors.initials: BH
authors.lastname: Hong
authors.forename: Kwan Yong
authors.initials: KY
authors.lastname: Choi
authors.forename: Hee Cheon
authors.initials: HC
authors.lastname: Lee
mesh_terms: D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008958:Models, Molecular; D011487:Protein Conformation; D011489:Protein Denaturation; D017510:Protein Folding; D016958:Pseudomonas putida / Q000201:enzymology; D013251:Steroid Isomerases / Q000737:chemistry* / Q000378:metabolism; D014508:Urea / Q000737:chemistry; D014978:Xenon / Q000737:chemistry*
chemical_list: D014978:Xenon; D014508:Urea; D013251:Steroid Isomerases