MF7000270 FAD-binding domain from mimivirus sulfhydryl oxidase R596 3gwn X-ray 1.78 Homodimer Acanthamoeba polyphaga mimivirus 19576902 Hakim M, Fass D J. Mol. Biol. 2009 4 391 758-68 Large double-stranded DNA viruses, including poxviruses and mimiviruses, encode enzymes to catalyze the formation of disulfide bonds in viral proteins produced in the cell cytosol, an atypical location for oxidative protein folding. These viral disulfide catalysts belong to a family of sulfhydryl oxidases that are dimers of a small five-helix fold containing a Cys-X-X-Cys motif juxtaposed to a flavin adenine dinucleotide cofactor. We report that the sulfhydryl oxidase pB119L from African swine fever virus (ASFV) uses for self-assembly surface different from that observed in homologs from mammals, plants, and fungi. Within a protein family, different packing interfaces for the same oligomerization state are extremely rare. We find that the alternate dimerization mode seen in ASFV pB119L is not characteristic of all viral sulfhydryl oxidases, as the flavin-binding domain from a mimivirus sulfhydryl oxidase assumes the same dimer structure as the known eukaryotic enzymes. ASFV pB119L demonstrates the potential of large double-stranded DNA viruses, which have faster mutation rates than their hosts and the tendency to incorporate host genes, to pioneer new protein folds and self-assembly modes. GO:0050660 flavin adenine dinucleotide binding GO:0016971 flavin-dependent sulfhydryl oxidase activity GO:0044423 virion component GO:0001889 liver development 2 1 Homooligomeric enzymes Homodimeric enzymes All chains according to the most probable oligomerization state stored in PDBe were considered. A Probable FAD-linked sulfhydryl oxidase R596 Acanthamoeba polyphaga mimivirus Q5UP54 33 144 38% MSLSKQVVPTHRVEIAPNSESTCKMDHSNYQHNGLITKIWGTAGWTFNHAVTFGYPLNPTSDDKRRYKNYFISLGDVLPCRLCRESYKKFITTGKTALTNEVLRNRHTLTKWFYDVHNAVNNKLEVDYGLSYEDVVNKYESFRAKCGKPVPTVKGCVTPLDHKAFSFKKLYYMDAPIVSLDKVENFVRIARMRGISDKYFCFLELATVLNGDFNELKKQSSWEYRNKYCQKKIRHMRENAIPSIEEQGYWKGTPTIDELKLLLFLCSNLNRTEVNDAINNVERLESTHYIEN 292 secondary structure helix 5 23 secondary structure helix 29 47 secondary structure helix 49 60 secondary structure helix 62 66 secondary structure helix 68 73 secondary structure helix 74 93 secondary structure helix 100 110 pfam PF04777 Erv1 / Alr family 43 125 B Probable FAD-linked sulfhydryl oxidase R596 Acanthamoeba polyphaga mimivirus Q5UP54 33 144 38% MSLSKQVVPTHRVEIAPNSESTCKMDHSNYQHNGLITKIWGTAGWTFNHAVTFGYPLNPTSDDKRRYKNYFISLGDVLPCRLCRESYKKFITTGKTALTNEVLRNRHTLTKWFYDVHNAVNNKLEVDYGLSYEDVVNKYESFRAKCGKPVPTVKGCVTPLDHKAFSFKKLYYMDAPIVSLDKVENFVRIARMRGISDKYFCFLELATVLNGDFNELKKQSSWEYRNKYCQKKIRHMRENAIPSIEEQGYWKGTPTIDELKLLLFLCSNLNRTEVNDAINNVERLESTHYIEN 292 secondary structure helix 5 23 secondary structure helix 29 47 secondary structure helix 49 60 secondary structure helix 61 66 secondary structure helix 68 73 secondary structure helix 74 93 secondary structure helix 100 110 pfam PF04777 Erv1 / Alr family 43 125 Insufficient evidence (candidate) The full structure participates in mutual synergistic folding. ERV/ALR sulfhydryl oxidase domain There is no information on the stability/disorder of the monomeric forms of FAD-linked sulfhydryl oxidases. The wild-type protein is a dimer in solution (analytical equilibrium ultracentrifugation) (PMID:19576902). The, large, hydrophobic interface is made up of two longer, nearly antiparallel helices per monomer that mediate helix packing interactions to form the interface. A N/A B N/A MF7000866 MF7000270 MF7000867 MF7000868 MF7000869 MF7000870