PDBsum entry 2d3w

Biosynthetic protein

PDB id: 2d3w

Contents

Protein chains

244 a.a. *

Waters ×34

* Residue conservation analysis

PDB id:

2d3w

Name:

Biosynthetic protein

Title:

Crystal structure of escherichia coli sufc, an atpase compenent of the suf iron-sulfur cluster assembly machinery

Structure:

Probable atp-dependent transporter sufc. Chain: a, b, c, d. Engineered: yes

Source:

Escherichia coli. Organism_taxid: 562. Expressed in: escherichia coli. Expression_system_taxid: 562.

Biol. unit:

Dimer (from PQS)

Resolution:

2.50Å R-factor: 0.224 R-free: 0.293

Authors:

S.Kitaoka,K.Wada,Y.Hasegawa,Y.Minami,Y.Takahashi,K.Fukuyama

Key ref:

S.Kitaoka et al. (2006). Crystal structure of Escherichia coli SufC, an ABC-type ATPase component of the SUF iron-sulfur cluster assembly machinery. FEBS Lett, 580, 137-143. PubMed id: 16364320 DOI: 10.1016/j.febslet.2005.11.058

Date:

03-Oct-05 Release date: 17-Jan-06

Protein chains

P77499  (SUFC_ECOLI) -  Probable ATP-dependent transporter SufC from Escherichia coli (strain K12)

Seq: 248 a.a.

Struc: 244 a.a.

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1016/j.febslet.2005.11.058

FEBS Lett 580:137-143 (2006)

PubMed id: 16364320

Crystal structure of Escherichia coli SufC, an ABC-type ATPase component of the SUF iron-sulfur cluster assembly machinery.

S.Kitaoka, K.Wada, Y.Hasegawa, Y.Minami, K.Fukuyama, Y.Takahashi.

ABSTRACT

SufC is an ATPase component of the SUF machinery, which is involved in the biosynthesis of Fe-S clusters. To gain insight into the function of this protein, we have determined the crystal structure of Escherichia coli SufC at 2.5A resolution. Despite the similarity of the overall structure with ABC-ATPases (nucleotide-binding domains of ABC transporters), some key differences were observed. Glu171, an invariant residue involved in ATP hydrolysis, is rotated away from the nucleotide-binding pocket to form a SufC-specific salt bridge with Lys152. Due to this salt bridge, D-loop that follows Glu171 is flipped out to the molecular surface, which may sterically inhibit the formation of an active dimer. Thus, the salt bridge may play a critical role in regulating ATPase activity and preventing wasteful ATP hydrolysis. Furthermore, SufC has a unique Q-loop structure on its surface, which may form a binding site for its partner proteins, SufB and/or SufD.

Selected figure(s)

Figure 2.
Fig. 2. A ribbon representation of the overall structure of E. coli SufC. The catalytic α/β domain is shown in green and the α-helical domain in blue. The motifs conserved in ABC-ATPases are depicted by different colors: Walker A motif, red; Walker B motif, magenta; ABC signature motif, yellow; Q-loop, orange; and D-loop, dark blue. The side chains of Lys152 and Glu171, which are involved in a salt bridge between the catalytic and helical domains, are represented by stick models in blue and magenta, respectively.

Figure 4.
Fig. 4. The dimer model of E. coli SufC and the conservation of the surface residues among the SufC orthologs. (A) A ribbon representation of the SufC dimer with the D-loops at the interface highlighted by thick lines. The model was obtained by superimposing two SufC structures onto the ATP-bound HlyB (H662A) dimer (PDB: 1XEF). Two ATP molecules at the interface of the HlyB dimer are included in the model (black sticks). The ABC signature motifs are shown in yellow. (B) A ConSurf image in the same orientation as in (A) for the SufC family. Conserved residues are shown in magenta, whereas variable sites are shown in white and highly variable sites in blue. (C) The ConSurf surface rotated 90° relative to the y-axis of the images shown in (A) and (B).

The above figures are reprinted by permission from the Federation of European Biochemical Societies: FEBS Lett (2006, 580, 137-143) copyright 2006.

Figures were selected by an automated process.