PDBsum entry 1k5u

Hormone/growth factor

PDB id: 1k5u

Contents

Protein chains

129 a.a. *

Ligands

SO4 ×3

Waters ×83

* Residue conservation analysis

PDB id:

1k5u

Name:

Hormone/growth factor

Title:

Human acidic fibroblast growth factor. 141 amino acid form with amino terminal his tag with his93 replaced by gly (h93g).

Structure:

Acidic fibroblast growth factor. Chain: a, b, c. Engineered: yes. Mutation: yes. Other_details: amino terminal his tag

Source:

Homo sapiens. Human. Organism_taxid: 9606. Expressed in: escherichia coli. Expression_system_taxid: 562

Resolution:

2.00Å R-factor: 0.233 R-free: 0.293

Authors:

J.Kim,S.I.Blaber,M.Blaber

Key ref:

J.Kim et al. (2002). Alternative type I and I' turn conformations in the beta8/beta9 beta-hairpin of human acidic fibroblast growth factor. Protein Sci, 11, 459-466. PubMed id: 11847269 DOI: 10.1110/ps.43802

Date:

12-Oct-01 Release date: 27-Feb-02

Protein chains

P05230  (FGF1_HUMAN) -  Fibroblast growth factor 1 from Homo sapiens

Seq: 155 a.a.

Struc: 129 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

DOI no: 10.1110/ps.43802

Protein Sci 11:459-466 (2002)

PubMed id: 11847269

Alternative type I and I' turn conformations in the beta8/beta9 beta-hairpin of human acidic fibroblast growth factor.

J.Kim, S.I.Blaber, M.Blaber.

ABSTRACT

Human acidic fibroblast growth factor (FGF-1) has a beta-trefoil structure, one of the fundamental protein superfolds. The X-ray crystal structures of wild-type and various mutant forms of FGF-1 have been solved in five different space groups: C2, C222(1), P2(1) (four molecules/asu), P2(1) (three molecules/asu), and P2(1)2(1)2(1). These structures reveal two characteristically different conformations for the beta8/beta9 beta-hairpin comprising residue positions 90-94. This region in the wild-type FGF-1 structure (P2(1), four molecules/asu), a his-tagged His93-->Gly mutant (P2(1), three molecules/asu) and a his-tagged Asn106-->Gly mutant (P2(1)2(1)2(1)) adopts a 3:5 beta-hairpin known as a type I (1-4) G1 beta-bulge (containing a type I turn). However, a his-tagged form of wild-type FGF-1 (C222(1)) and a his-tagged Leu44-->Phe mutant (C2) adopt a 3:3 beta-hairpin (containing a type I' turn) for this same region. A feature that distinguishes these two types of beta-hairpin structures is the number and location of side chain positions with eclipsed C(beta) and main-chain carbonyl oxygen groups (Psi is equivalent to +60 degrees). The effects of glycine mutations upon stability, at positions within the hairpin, have been used to identify the most likely structure in solution. Type I' turns in the structural data bank are quite rare, and a survey of these turns reveals that a large percentage exhibit crystal contacts within 3.0 A. This suggests that many of the type I' turns in X-ray structures may be adopted due to crystal packing effects.

Selected figure(s)

Figure 1.
Fig. 1. Relaxed stereodiagram of human FGF-1 (Blaber et al. 1996) showing the location of the ß8/ß9 turn region and the 90-94 ß-hairpin (dark gray). The view is down the pseudo threefold axis of symmetry present in the ß-trefoil architecture. Region 90-94 is related to the N- and C-termini by this internal symmetry.

Figure 4.
Fig. 4. Distribution of the distances between type I` turns and crystal contacts from 116 type I` turns in the structural databank.

The above figures are reprinted by permission from the Protein Society: Protein Sci (2002, 11, 459-466) copyright 2002.

Figures were selected by the author.