Using proteomics to identify potential vaccines components against Bordetella pertussis

PEREZ VIDAKOVICS, M. LAURA; PABA MARTINEZ, JAIME; LAMBERTI, YANINA; RICART, CARLOS ANDRÉ; DEL VALLE SOUSA, MARCELO; MARCELO AND RODRIGUEZ, M. EUGENIA

Pinamar, Buenos Aires, Argentina.

Congreso; XLI Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB). X Congreso de la Panamerican association for Biochemistry and Molecular Biology (PABMB).; 2005

B. pertussis (Bp), the etiological agent of whooping cough in humans, is currently re-emerging despite vaccination. The study of the infective phenotype of this pathogen showed that under iron deprivation it differentially expresses in vivo immunogenic proteins that are not included in any of the currently used vaccines. Additionally, an increased virulence was detected in this phenotype. The proteomic approach was used to analyze the pattern of differential protein expression during iron deprivation of Bp. Independent gel duplicates of both iron-restricted or iron-sufficient growth conditions were analyzed. In average gel 900 spots of each condition were detected. Only the spots with a relative intensity difference  300% were considered as differential. Using tryptic digestion and MALDI-TOF MS we identified four proteins with differential expression in absence of iron: a superoxide dismutase (SodA), an hemin transport protein (BhuR), an hypothetical protein, and a putative lipoprotein. The identified proteins might help to explain the increased virulence of this phenotype. Intracellular survival of the bacteria during oxidative burst in phagocytes may be at least partly favored by the increased expression of SodA under iron-restricted conditions whereas BhuR, being an outer membrane protein, might be involved in bacterial interaction with the host. Further studies are being conducted to gain a better insight into their role in bacterial pathogenesis and their potential as vaccine components.