title: Helicobacter pylori secretes the chaperonin GroEL (HSP60), which binds iron.
abstract: Helicobacter pylori is a bacterium that can use multiple iron sources. However, it is unknown whether this bacterium secretes molecules such as siderophores or haemophores to scavenge iron. Here, we report the first secreted iron-binding protein of H. pylori, which we purified by haem-affinity chromatography. Mass spectrometry analysis revealed its identity as chaperonin (HpGroEL). When we compared HpGroEL with EcGroEL from Escherichia coli, they were homologous, showing 60% similarity. Additionally, purified cytoplasmic HpGroEL could also bind iron. Perhaps H. pylori secretes HpGroEL to maintain the appropriate folding of extracellular proteins and to bind iron.
authors.affiliation: Posgrado en Ciencias Genómicas, Universidad Autónoma de la Ciudad de México, San Lorenzo 290, Col Del Valle, México DF, Mexico.
authors.forename: Marco Antonio
authors.initials: MA
authors.lastname: González-López
authors.forename: Norma
authors.initials: N
authors.lastname: Velázquez-Guadarrama
authors.forename: María Elena
authors.initials: ME
authors.lastname: Romero-Espejel
authors.forename: José de Jesús
authors.initials: Jde J
authors.lastname: Olivares-Trejo
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D018834:Chaperonin 60 / Q000737:chemistry / Q000378:metabolism*; D016480:Helicobacter pylori / Q000378:metabolism*; D006418:Heme / Q000378:metabolism; D007501:Iron / Q000378:metabolism*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011485:Protein Binding; D017386:Sequence Homology, Amino Acid
chemical_list: D001426:Bacterial Proteins; D018834:Chaperonin 60; D006418:Heme; D007501:Iron