Stable isotope aided nuclear magnetic resonance study to investigate the receptor-binding site of human interleukin 1 beta.
Resonance assignments for interleukin 1 beta at neutral pH were made by using three-dimensional NMR in combination with specific labeling and double-labeling methods with stable isotopes. On the basis of the present assignments, 15N single-quantum coherence spectra of N-terminal truncated and fusion mutants were compared with that of the wild-type. Although these mutants have reduced biological activity, they showed 15N-SQC spectra similar to that of the wild-type. However, small but significant chemical shift changes were observed for amino acid residues within a loop 86-99, in spite of the modification at the N-terminus, supporting the idea that this loop forms a biologically active part of interleukin 1 beta. Receptor-binding activity was studied for mutants (Asp-93)-, (Leu-93)- and des-(Arg-98)interleukin 1 beta's. The results show significant loss of the receptor-binding activity. The N-terminus, the C-terminus, and the loop 86-99 form a part of the open end of a beta-barrel [Finzel, B. C., Clancy, L. L., Holland, D. R., Muchmore, S. W., Watenpaugh, K. D., & Einspahr, H. M. (1989) J. Mol. Biol. 209, 779-791; Clore, G. M., Wingfield, P. T., & Gronenborn, A. M. (1991) Biochemistry 30, 2315-2323], which forms the receptor-binding site of IL-1 beta.
Tate
S
S
Tokyo Metropolitan Institute of Medical Science, Japan.
Kikumoto
Y
Y
Ichikawa
S
S
Kaneko
M
M
Masui
Y
Y
Kamogashira
T
T
Ouchi
M
M
Takahashi
S
S
Inagaki
F
F
D000577:Amides / Q000737:chemistry; D000595:Amino Acid Sequence; D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007375:Interleukin-1 / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D051379:Mice; D008969:Molecular Sequence Data; D009154:Mutation; D009587:Nitrogen Isotopes; D011485:Protein Binding; D011487:Protein Conformation; D011971:Receptors, Immunologic / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D017472:Receptors, Interleukin-1; D012996:Solutions; D014867:Water
D000577:Amides; D007375:Interleukin-1; D009587:Nitrogen Isotopes; D011971:Receptors, Immunologic; D017472:Receptors, Interleukin-1; D012996:Solutions; D014867:Water