Crystal structure of the iron-sulfur cluster transfer protein ApbC from Escherichia coli

• Published in: Biochemical and biophysical research communications Vol. 722; p. 150167
• Main Authors: Yang, Jingyu, Duan, Ya-Fei, Liu, Lin
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 30.08.2024
• Subjects: Crystal structure; Dimerization; Disulfide bond; Iron-sulfur clusters; Iron-sulfur clusters; Disulfide bond; Dimerization; Crystal structure
• ISSN: 0006-291X; 1090-2104; 1090-2104
• DOI: 10.1016/j.bbrc.2024.150167

Iron-sulfur (Fe–S) clusters are ubiquitous and are necessary to sustain basic life processes. The intracellular Fe–S clusters do not form spontaneously and many proteins are required for their biosynthesis and delivery. The bacterial P-loop NTPase family protein ApbC participates in Fe–S cluster assembly and transfers the cluster into apoproteins, with the Walker A motif and CxxC motif being essential for functionality of ApbC in Fe–S protein biogenesis. However, the structural basis underlying the ApbC activity and the motifs’ role remains unclear. Here, we report the crystal structure of Escherichia coli ApbC at 2.8 Å resolution. The dimeric structure is in a W shape and the active site is located in the 2-fold center. The function of the motifs can be annotated by structural analyses. ApbC has an additional N-terminal domain that differs from other P-loop NTPases, possibly conferring its inherent specificity in vivo. •Crystal structure of the bacterial iron-sulfur cluster transfer protein ApbC was solved at 2.8 Å resolution.•ApbC exists as a dimer and has a candidate [4Fe–4S] site and two nucleotide-binding sites at the dimer interface.•Structural comparison reveals the roles of CxxC motif and Walker A motif.