Abstract
The P61 protein is an immunodominant antigen of Nocardia brasiliensis that is observed in the sera from patients infected with the bacterium. However, the B-cell epitopes of N. brasiliensis are still unresolved. To identify the antigenic determinants of P61, we screened seven monoclonal antibodies (mAbs) against P61 protein that was expressed in the Escherichia coli system. A series of truncated peptides of P61 were then generated and the mAbs were used to screen these peptides by Western blot analyses. Three B-cell epitopes were recognized by the P61 specific mAbs: 461-FEYWTKVDPEIGKRIEEG-478, 427-LVREVFNDAQRDRLVSNVVGGVQEPV. LSRVFEYWTKVDPEIGKRIEEGVRAG-482, and 447-HVLGGVQEPVLSRVFEY WTKVDPEI GKRIEEGVRAGLD-484. The latter two epitopes were further identified by N. brasiliensis-infected mouse serum. These results facilitate future investigations of serodiagnostic methods to identify Nocardia infections.
Highlights
Nocardia brasiliensis is a facultative, intracellular, filamentous, gram-positive, and partially acid-fast bacterium that infects skin via traumatic inoculation
Western blot analysis further revealed that the P61 protein can be identified by the endogenous antibodies present in serum from N. brasiliensisinfected mice (Figure 1C)
The peptide within the amino acid sequence 461– 478 aa did not react at all with the infected serum. These results suggest that the screened epitopes at positions 427–482 and 447– 484 aa are robustly identified by N. brasiliensis-positive mouse serum, and can potentially be used as markers for the diagnosis of nocardiosis caused by N. brasiliensis infection
Summary
Nocardia brasiliensis is a facultative, intracellular, filamentous, gram-positive, and partially acid-fast bacterium that infects skin via traumatic inoculation. Infections can be transmitted via cutaneous or respiratory inhalation resulting in CNS disease (Smego and Gallis, 1984; Beaman and Beaman, 1994; Chen et al, 2016). Primary cutaneous nocardiosis is an infectious disease caused by bacteria in the genus Nocardia, but is most often caused by N. brasiliensis infection (Smego and Gallis, 1984; Wilson, 2012; Chen et al, 2016). N. brasiliensis is the primary etiologic agent of human mycetoma in Mexico, and about 86% of the mycetoma cases there are caused by the bacterium (Lopez Martinez et al, 1992; Salinas-Carmona et al, 1992; Licón-Trillo et al, 2003; Castro-Matteotti et al, 2008). The confirmation of its presence using conventional microbiological techniques usually takes quite a long time, and it is difficult
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
