PDBsum entry 2f1e

Structural genomics, unknown function

PDB id: 2f1e

Contents

Protein chain

116 a.a. *

* Residue conservation analysis

PDB id:

2f1e

Name:

Structural genomics, unknown function

Title:

Solution structure of apag protein

Structure:

Protein apag. Chain: a. Engineered: yes

Source:

Xanthomonas axonopodis pv. Citri. Organism_taxid: 92829. Strain: pv. Citri. Gene: apag. Expressed in: escherichia coli. Expression_system_taxid: 562.

NMR struc:

20 models

Authors:

G.Contessa,T.A.Pertinhez,A.Spisni,M.Paci,C.S.Farah,D.O.Cicero

Key ref:

D.O.Cicero et al. (2007). Solution structure of ApaG from Xanthomonas axonopodis pv. citri reveals a fibronectin-3 fold. Proteins, 67, 490-500. PubMed id: 17256769 DOI: 10.1002/prot.21277

Date:

14-Nov-05 Release date: 24-Oct-06

Protein chain

Q8PP26  (APAG_XANAC) -  Protein ApaG from Xanthomonas axonopodis pv. citri (strain 306)

Seq: 127 a.a.

Struc: 116 a.a.

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1002/prot.21277

Proteins 67:490-500 (2007)

PubMed id: 17256769

Solution structure of ApaG from Xanthomonas axonopodis pv. citri reveals a fibronectin-3 fold.

D.O.Cicero, G.M.Contessa, T.A.Pertinhez, M.Gallo, A.M.Katsuyama, M.Paci, C.S.Farah, A.Spisni.

ABSTRACT

ApaG proteins are found in a wide variety of bacterial genomes but their function is as yet unknown. Some eukaryotic proteins involved in protein-protein interactions, such as the human polymerase delta-interacting protein (PDIP38) and the F Box A (FBA) proteins, contain ApaG homology domains. We have used NMR to determine the solution structure of ApaG protein from the plant pathogen Xanthomonas axonopodis pv. citri (ApaG(Xac)) with the aim to shed some light on its molecular function. ApaG(Xac) is characterized by seven antiparallel beta strands forming two beta sheets, one containing three strands (ABE) and the other four strands (GFCC'). Relaxation measurements indicate that the protein has a quite rigid structure. In spite of the presence of a putative GXGXXG pyrophosphate binding motif ApaG(Xac) does not bind ATP or GTP, in vitro. On the other hand, ApaG(Xac) adopts a fibronectin type III (Fn3) fold, which is consistent with the hypothesis that it is involved in mediating protein-protein interactions. The fact that the proteins of ApaG family do not display significant sequence similarity with the Fn3 domains found in other eukaryotic or bacterial proteins suggests that Fn3 domain may have arisen earlier in evolution than previously estimated.

Selected figure(s)

Figure 2.
Figure 2. Structure of ApaG[Xac]. (A) and (B) Topological representation of ApaG[Xac] (C) Stereo view of an overlay of the backbone atoms of 20 superimposed structures. (D) Ribbon representation of the structure.

Figure 5.
Figure 5. (A) Comparison of the 3D structure of ApaG[Xac] (left) and NCAM F3 Module 2 (1LWR, right). The topology of ApaG[Xac] is identical to that of FN3 modules, but with significantly longer strands B, C , and E (depicted in red). (B) Superimposition of ApaG[Xac] (green) and (O-glycosyl) galactosidase (1BGL, red).

The above figures are reprinted by permission from John Wiley & Sons, Inc.: Proteins (2007, 67, 490-500) copyright 2007.

Figures were selected by an automated process.