Identification of Immunodominant Outer Membrane Proteins of Fusobacterium necrophorum from Severe Ovine Footrot By MALDI-TOF Mass Spectrometry

• Published in: Current microbiology 2021-04, Vol.78 (4), p.1298-1304
• Main Authors: Farooq, S., Wani, S. A., Qureshi, S., Bhat, M. A., Kashoo, Z. A., Hussain, I.
• Format: Article
• Language: English
• Subjects: Amino acid sequence; Animals; Bacteria; Bacterial Outer Membrane Proteins - genetics; Biomedical and Life Sciences; Biotechnology; Electrophoresis; Feet; Foot Rot; Fusobacterium necrophorum; Gels; Goats; Gram-negative bacteria; Immunogenicity; Ionization; Ions; Life Sciences; Mass spectrometry; Mass spectroscopy; Membrane Proteins; Membranes; Microbiology; Outer membrane proteins; Pore formation; Pore-forming proteins; Proteins; Rabbits; Scientific imaging; Sheep; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Spectroscopy; Western blotting
• ISSN: 0343-8651; 1432-0991
• DOI: 10.1007/s00284-021-02383-2

The aim of this study was to identify the immunodominant outer membrane proteins (OMPs) of Fusobacterium necrophorum from sheep affected with severe foot-rot. The OMP profile of ovine strains of F. necrophorum has not been well studied. We analyzed the OMP profile of the most frequent lktA variant JKS-F3 of F. necrophorum associated with severe ovine foot-rot with lesion score 4 in order to identify its major immunodominant OMPs. Electrophoretic separations of extracted OMPs showed a number of spots in two-dimensional electrophoretic gels. Two immunoreactive proteins of size around 43 kDa were identified through western blotting using hyperimmune sera raised in rabbits. These two immunogenic OMPs were analyzed by Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF/MS) which revealed that these two OMPs of lktA variant JKS-F3 of F. necrophorum showed 46 and 42 percent protein sequence coverage and scores of 125 and 114, respectively, with the reported 43 kDa outer membrane protein of F. necrophorum strain H05, a putative porin having properties similar to pore-forming proteins of anaerobic Gram-negative bacteria. These identified immunogenic OMPs will contribute to our understanding of the pathogenic role played by this organism in ovine foot-rot and could be exploited to devise an effective control strategy through development of an OMP-based recombinant vaccine to mitigate foot-rot in sheep and goats.