PDBsum entry 1i16

Cytokine

PDB id: 1i16

Contents

Protein chain

130 a.a. *

* Residue conservation analysis

PDB id:

1i16

Name:

Cytokine

Title:

Structure of interleukin 16: implications for function, nmr, 20 structures

Structure:

Interleukin 16. Chain: a. Synonym: lcf. Engineered: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606. Cell_line: bl21. Cell: cd8+ t cells. Cellular_location: extracellular. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008.

NMR struc:

20 models

Authors:

P.Muehlhahn,M.Zweckstetter,J.Georgescu,C.Ciosto,C.Renner, M.Lanzendoerfer,K.Lang,D.Ambrosius,M.Baier,R.Kurth,T.A.Holak

Key ref:

P.Mühlhahn et al. (1998). Structure of interleukin 16 resembles a PDZ domain with an occluded peptide binding site. Nat Struct Biol, 5, 682-686. PubMed id: 9699630 DOI: 10.1038/1376

Date:

20-May-98 Release date: 25-May-99

Protein chain

Q14005  (IL16_HUMAN) -  Pro-interleukin-16 from Homo sapiens

Seq: 1332 a.a.

Struc: 130 a.a.

DOI no: 10.1038/1376

Nat Struct Biol 5:682-686 (1998)

PubMed id: 9699630

Structure of interleukin 16 resembles a PDZ domain with an occluded peptide binding site.

P.Mühlhahn, M.Zweckstetter, J.Georgescu, C.Ciosto, C.Renner, M.Lanzendörfer, K.Lang, D.Ambrosius, M.Baier, R.Kurth, T.A.Holak.

ABSTRACT

The structure of a folded core of IL-16 is similar to that of intracellular protein modules called PDZ domains. IL-16 is thus the first extracellular protein found to have a PDZ-like fold. However, it does not exhibit normal peptide binding properties of PDZ domains. This is due to alterations of the structure at the 'PDZ-like binding site' of IL-16 (the GLGF cleft): the GLGF cleft of IL-16 is much smaller than those of PDZ-domains and is additionally blocked with a tryptophan side chain at its center. Our experiments indicate also that IL-16 nonspecifically aggregates in solution; but formation of a homo-tetrameric protein is not required, in contrast to previous suggestions, for its chemo-attractant activity.

Selected figure(s)

Figure 1.
Figure 1. a, Steady-state heteronuclear ^15N{^1 H}-NOE for the backbone amides of IL-16. Residues for which no results are shown correspond either to prolines or to residues for which the relaxation data could not be extracted. b, ^1H-^15N HSQC spectrum of human IL-16^1−130 at pH 7.4, circles identify residues for which cross peaks were observed only at pH 6.5.

Figure 4.
Figure 4. a, Comparison of the overall topologies of IL-16 and Dlg_A. b, Conformation of the Gly-Leu-Gly-Phe cleft in human IL-16 (red).The side chain of Trp 99 is marked in green. Conformation of the side chain atoms for residues 41−46 are also shown. Conformation of the GLGF site in human Dlg_A is in blue^22. The side chain of Ala 529 is shown in green (this residue corresponds to Trp 99 in IL-16).

The above figures are reprinted by permission from Macmillan Publishers Ltd: Nat Struct Biol (1998, 5, 682-686) copyright 1998.

Figures were selected by an automated process.