Actinobacillus seminis GroEL-homologous protein agglutinates sheep erythrocytes
- 44 Downloads
Actinobacillus seminis, a commensal of ovine and caprine reproductive organs, is able to induce epididymitis in the small ruminants that it infects. In this work, we characterised two protein bands of approximately 150 kDa and 65 kDa. These proteins cross-reacted with a polyclonal serum against Gallibacterium anatis hemagglutinin and with a polyclonal serum from sheep with epididymitis, indicating that the proteins are expressed in vivo; the two proteins also interacted with biotin-labeled sheep fibrinogen and fibronectin, suggesting that they may function as adhesins. The participation of these proteins as adhesins was confirmed by a cultured human bladder cell-A. seminis adhesion assay and adherence inhibition by preincubation of A. seminis with polyclonal antiserum to the 150 kDa protein. Both proteins presented sequence identity with an A. seminis GroEL protein by mass spectrometry analysis and agglutinated glutaraldehyde-fixed sheep red blood cells. Immunogold labeling was observed by transmission electron microscopy on bacterial cells that were negatively stained, and a peroxidase reaction was detected in A. seminis biofilms, when an anti-A. seminis 150 kDa protein serum was used, indicating the presence of this protein on the surface of A. seminis and in biofilms. The A. seminis GroEL-homologue is a multifunctional protein that likely acts as a hemagglutinin.
KeywordsA. seminis GroEL Hemagglutinin Adhesin
Outer membrane protein
Transmission electron microscopy
This study was funded by grants from DGAPA-UNAM PAPIIT IN215616 and IN219919. FMG is a doctoral student supported by a scholarship from CONACYT (283503).
Conflict of interest
The authors declare that they have no conflicts of interest.
- Berne C, Ducret A, Hardy GG, Brun YV (2015) Adhesins involved in attachment to abiotic surfaces by gram-negative bacteria. Microbiol Spectr. https://doi.org/10.1128/microbiolspec.mb-0018-2015 CrossRefPubMedPubMedCentralGoogle Scholar
- Dibarrat JA, Aparicio ED, Reynoso BA, Aparicio BD, Gutiérrez VRT, Pérez JT (2006) Inducción experimental de epididimitis en ovinos por inoculación intrauretral con Actinobacillus seminis: estudio bacteriológico, serológico e histopatológico. Rev Tec Pec México 44:257–267Google Scholar
- Genetzky RM (1995) Epididymitis in rams. Compend Contin Educ Pract Vet 17:447Google Scholar
- López-Ochoa J, Montes-García JF, Vázquez C, Sánchez-Alonso P, Pérez-Márquez VM, Blackall PJ, Vaca S, Negrete-Abascal E (2017) Gallibacterium elongation factor-Tu possesses amyloid-like protein characteristics, participates in cell adhesion, and is present in biofilms. J Microbiol 55:745–752. https://doi.org/10.1007/s12275-017-7077-0 CrossRefPubMedGoogle Scholar
- Montes-García JF, Vaca S, Delgado NL, Uribe-García A, Vázquez C, Sánchez Alonso P, Xicohtencatl Cortes J, Cruz Cordoba A, Negrete-Abascal E (2018a) Mannheimia haemolytica OmpP2-like is an amyloid-like protein, forms filaments, takes part in cell adhesion and is part of biofilms. Antonie Van Leeuwenhoek 111:2311–2321. https://doi.org/10.1007/s10482-018-1122-9 CrossRefPubMedGoogle Scholar
- Montes-García JF, Chincoya Martinez DA, Vaca Pacheco S, Vázquez Cruz C, Sánchez Alonso P, Xicohtencatl Cortes J, Trujillo-Ruiz H, Negrete-Abascal E (2018b) Identification of two adhesins of Actinobacillus seminis. Small Rumin Res 167:100–103. https://doi.org/10.1016/j.smallrumres.2018.08.013 CrossRefGoogle Scholar
- Negrete-Abascal E, Montes-Garcia F, Vaca-Pacheco S, Leyto-Gil AM, Fragoso-Garcia E, Carvente-Garcia R, Perez-Agüeros S, Castelan-Sanchez HG, Garcia-Molina A, Villamar TE, Sánchez-Alonso P, Vazquez-Cruz C (2018) Genome sequence of Actinobacillus seminis strain ATCC 15768, a reference strain of ovine pathogens that causes infections in reproductive organs. Genome Announc. https://doi.org/10.1128/genomea.01453-17 CrossRefPubMedPubMedCentralGoogle Scholar