title: The intrachain disulfide bridge is responsible of the unusual stability properties of novel acylphosphatase from Escherichia coli.
abstract: Acylphosphatase (AcP) activity in prokaryotes was classically attributed to some aspecific acid phosphatases. We identified an open reading frame for a putative AcP in the b0968 Escherichia coli gene and purified the recombinant enzyme after checking by RT-PCR that it was indeed expressed. EcoAcP has a predicted typical fold of the AcP family but displays a very low specific activity and a high structural stability differently from its mesophilic and similarly to its hyperthermophilic counterparts. Site directed mutagenesis suggests that, together with other structural features, the intrachain S-S bridge in EcoAcP is involved in a remarkable thermal and chemical stabilization of the protein without affecting its catalytic activity.
authors.affiliation: Department of Biochemical Sciences, University of Florence, V.le Morgagni 50, 50134 Firenze, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Ramazzotti
authors.forename: Claudia
authors.initials: C
authors.lastname: Parrini
authors.forename: Massimo
authors.initials: M
authors.lastname: Stefani
authors.forename: Giampaolo
authors.initials: G
authors.lastname: Manao
authors.forename: Donatella
authors.initials: D
authors.lastname: Degl'Innocenti
mesh_terms: D017766:Acid Anhydride Hydrolases / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D002942:Circular Dichroism; D003545:Cysteine / Q000235:genetics / Q000378:metabolism; D004220:Disulfides / Q000378:metabolism*; D004795:Enzyme Stability; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D011489:Protein Denaturation / Q000187:drug effects; D016415:Sequence Alignment; D013696:Temperature; D013816:Thermodynamics; D014508:Urea / Q000494:pharmacology; D000097024:Acylphosphatase
chemical_list: D017766:Acid Anhydride Hydrolases; D003545:Cysteine; D004220:Disulfides; D007527:Isoenzymes; D014508:Urea; D000097024:Acylphosphatase