PDBsum entry 1lfn

Transferase

PDB id: 1lfn

Contents

Protein chain

305 a.a.

References listed in PDB file

Key reference

Title

Molecular replacement solution of the structure of apolactoferrin, A protein displaying large-Scale conformational change.

Authors

G.E.Norris, B.F.Anderson, E.N.Baker.

Ref.

Acta Crystallogr B, 1991, 47, 998.

PubMed id

1772635

Abstract

The crystal structure of an orthorhombic form of human apolactoferrin (ApoLf) has been determined from 2.8 A diffractometer data by molecular replacement methods. A variety of search models derived from the diferric lactoferrin structure (Fe2Lf) were used to obtain a consistent solution to the rotation function. An R-factor search gave the correct translational solution and the model was refined by rigid-body least-squares refinement (program CORELS). Only three of the four domains were located correctly by this procedure, however; the fourth was finally placed correctly by rotating it manually onto three strands of electron density which were recognized as part of its central beta-sheet. The final model, refined by restrained least-squares methods to an R factor of 0.214 for data in the resolution range 10.0 to 2.8 A, shows a large domain movement in the N-terminal half of the molecule (a 54 degree rotation of domain N2) and smaller domain movements elsewhere, when compared with Fe2Lf. A feature of the crystal structure is that although the ApoLf and Fe2Lf unit cells appear very similar, their crystal packing and molecular structures are quite different.

Secondary reference #1

Title

A family of human cdc2-Related protein kinases.

Authors

M.Meyerson, G.H.Enders, C.L.Wu, L.K.Su, C.Gorka, C.Nelson, E.Harlow, L.H.Tsai.

Ref.

Embo J, 1992, 11, 2909-2917.

PubMed id

1639063

Secondary reference #2

Title

The structural basis for specificity of substrate and recruitment peptides for cyclin-Dependent kinases.

Authors

N.R.Brown, M.E.Noble, J.A.Endicott, L.N.Johnson.

Ref.

Nat Cell Biol, 1999, 1, 438-443. [DOI no: 10.1038/15674]

PubMed id

10559988

Figure 1.
Figure 1. The location of the peptide-binding sites on phospho-CDK2 -cyclin A3 complex. CDK2 is shown in yellow with the C (PSTAIRE) helix in red and the activation segment in magenta. Cyclin A3 is shown in khaki. a, Conventional view of the CDK2 -cyclin A3 complex, also showing the peptide substrate (green ball-and-stick diagram) and the recruitment peptide (cyan ball-and-stick diagram). Note that the structures of the phospho-CDK2 -cyclin A3 -peptide complexes were determined separately. b, Dimeric phospho-CDK2 -cyclin A3 complexes. The phospho-CDK2 -cyclin A3 -peptide complexes in the crystal formed dimers, with the two complexes related by a non-crystallographic two-fold axis, in an arrangement similar to that of the phospho-CDK2 -cyclin A3 crystal (coordinates 1JST)5, which crystallized in a different space group to the peptide complexes. The contacts across the dimer interface are between the -sheet region of CDK2 (end of 2 and start of 3) and the groove between helices in cyclin A3 (helices 3 and 5). c, Surface representation of the substrate-peptide-binding pocket of CDK2, showing the site for proline at P+1 and the proximity of lysine at P+3 to cyclin A3. d, Surface representation of the recruitment-peptide complex. Diagrams generated in AESOP (M.E.M.N., unpublished observations).

Figure 3.
Figure 3. The recruitment-peptide-binding site of the phospho-CDK2 -cyclin A3 complex. a, Diagram showing residues RRLFGE from the recruitment peptide of p107 bound at the hydrophobic site on cyclin A3, making contacts with residues from successive turns of the 1 and 3 helices. The view, which is rotated ~90° from that shown in Fig. 2, shows the complete fold of the cyclin box. b, Similar view of the equivalent residues from the phospho-CDK2 -cyclin A3 -p27^KIP1 complex (coordinates IJSU from the PDB^25).

The above figures are reproduced from the cited reference with permission from Macmillan Publishers Ltd