Characterization and identification of the immunoreactive 35 kilodalton periplasmic iron-regulated protein of Mannheimia (Pasteurella) haemolytica

dc.contributor.advisor Louisa B. Tabatabai Belzer, Carol
dc.contributor.department Veterinary Microbiology and Preventive Medicine 2018-08-24T18:16:15.000 2020-07-02T05:53:17Z 2020-07-02T05:53:17Z Mon Jan 01 00:00:00 UTC 2001 2001-01-01
dc.description.abstract <p>Mannheimia (Pasteurella) haemolytica A1 is a bacterial pathogen associated with bovine respiratory disease (BRD) also known as shipping fever. Most bacterial pathogens have developed one of two iron acquisition systems, either a high affinity siderophore acquisition system or an outer membrane transferrin/lactoferrin receptor system. The iron acquisition system allows the pathogenic bacteria to obtain iron from the host's iron binding proteins. Pasteurella haemolytica A1 uses the latter mechanism. When P. haemolytica is grown under iron-deficient conditions, three periplasmic iron-regulated proteins (PIRPs) are expressed. The expressed PIRPs had molecular weights of 31, 35, and 45 kilodalton (kDa). The 35-kDa PIRP from P. haemolytica serovar A1 has been isolated from osmotic shock fluids with a two step ammonium sulfate precipitation procedure. The purified and characterized protein had an isoelectric pH (pI) of 6.8 and a molecular weight of 35,822. Equilibrium velocity ultracentrifugation established that the protein existed as a monomer under native conditions with a Mr of 33,795. The secondary structure revealed the protein contained 34.1% alpha helical structure, 16.8% beta sheet, 31.1% beta turns, and 17.9% random structure. The N-terminal sequence of the protein was ANEVNVYSYRQPYLIEPMLK. The 35-kDa protein was identified from the N-terminal sequence as the FbpA homologue of the Haemophilus influenzae iron transport protein. Expression of the iron-regulated protein was inhibited by Fe3+ and by Fe2+, but not by Cu2+ , Co2+, Ni2+, Mn2+, and Zn2+. P. haemolytic up-regulated and expressed receptors for transferrin, hemoglobin, and lactoferrin to obtain iron, but did not produce siderophores to acquire iron. Receptors for hemoglobin and lactoferrin have not been described previously for P. haemolytica A1. Most cattle had low antibody levels to the 35-kDa protein. Therefore, the 35-kDa FpbA would not be a good candidate for a serologic test for detection of antibody to P. haemolytica. The results also showed that convalescent cattle had high IgG antibody levels to the 35-kDa FpbA, suggesting the 35-kDa protein could be a potential component for an improved vaccine.</p>
dc.format.mimetype application/pdf
dc.identifier archive/
dc.identifier.articleid 1625
dc.identifier.contextkey 6078055
dc.identifier.s3bucket isulib-bepress-aws-west
dc.identifier.submissionpath rtd/626
dc.language.iso en
dc.source.bitstream archive/|||Sat Jan 15 01:19:12 UTC 2022
dc.subject.disciplines Immunology and Infectious Disease
dc.subject.disciplines Medical Immunology
dc.subject.disciplines Microbiology
dc.subject.disciplines Veterinary Pathology and Pathobiology
dc.subject.keywords Veterinary microbiology and preventive medicine
dc.subject.keywords Immunobiology
dc.title Characterization and identification of the immunoreactive 35 kilodalton periplasmic iron-regulated protein of Mannheimia (Pasteurella) haemolytica
dc.type article
dc.type.genre dissertation
dspace.entity.type Publication
relation.isOrgUnitOfPublication 16f8e472-b1cd-4d8f-b016-09e96dbc4d83 dissertation Doctor of Philosophy
Original bundle
Now showing 1 - 1 of 1
1.95 MB
Adobe Portable Document Format