title: Lpp34, a novel putative lipoprotein from Mycobacterium avium subsp. paratuberculosis.
abstract: A Mycobacterium avium subsp. paratuberculosis expression library in lambda ZAP was screened with immunized mice sera. One clone was selected, sequenced and further characterized. The sequence analysis of the hypothetical open-reading frame (ORF) predicts a protein of 20.8 kDa with a probable signal sequence compatible with Cys-acylation at Cys24, characteristic of lipoproteins. In consequence, the protein was termed Lpp34. Recombinant expression of Lpp34 was achieved by cloning the lpp34 gene into the histidine-tag expression vector pRSET-A. Western blot analysis showed a protein band with a molecular weight of 34 kDa. The native protein was localized in the membrane fraction of M. avium subsp. paratuberculosis and extracted in the detergent phase of Triton X-114. Southern blot and polymerase chain reaction showed that the gene is absent from all the non-M. avium complex mycobacterial genomes tested. Humoral reactivity using bovine sera demonstrated that this protein is widely recognized by both the infected and non-infected animals. This could partly be due to the conserved sequence in close-related environmental bacteria such as M. avium subsp. avium and to the presence of a conserved epitope in other bacteria such as Escherichia coli. In conclusion, these findings show that Lpp34 is a membrane protein and a putative lipoprotein present in M. avium complex mycobacteria and absent in the M. tuberculosis complex.
authors.affiliation: Instituto de Biotecnología, CICVyA, INTA, Castelar, Argentina.
authors.forename: A
authors.initials: A
authors.lastname: Gioffré
authors.forename: K
authors.initials: K
authors.lastname: Caimi
authors.forename: M J
authors.initials: MJ
authors.lastname: Zumárraga
authors.forename: V
authors.initials: V
authors.lastname: Meikle
authors.forename: C
authors.initials: C
authors.lastname: Morsella
authors.forename: F
authors.initials: F
authors.lastname: Bigi
authors.forename: A
authors.initials: A
authors.lastname: Alito
authors.forename: M P
authors.initials: MP
authors.lastname: Santángelo
authors.forename: F
authors.initials: F
authors.lastname: Paolicchi
authors.forename: M I
authors.initials: MI
authors.lastname: Romano
authors.forename: A
authors.initials: A
authors.lastname: Cataldi
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000145:classification / Q000276:immunology / Q000302:isolation & purification*; D001483:Base Sequence; D015153:Blotting, Western / Q000662:veterinary; D002417:Cattle; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000032:analysis; D008074:Lipoproteins / Q000145:classification / Q000276:immunology / Q000302:isolation & purification*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016927:Mycobacterium avium subsp. paratuberculosis / Q000145:classification / Q000276:immunology* / Q000302:isolation & purification*; D016366:Open Reading Frames; D016133:Polymerase Chain Reaction / Q000662:veterinary; D011994:Recombinant Proteins / Q000145:classification / Q000276:immunology / Q000302:isolation & purification; D017422:Sequence Analysis, DNA; D020539:Sequence Analysis, Protein
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D008074:Lipoproteins; D011994:Recombinant Proteins