The Bordetella genus is divided into two groups: classical and non-classical. Bordetella pertussis, Bordetella bronchiseptica and Bordetella parapertussis are known as classical bordetellae, a group of important human pathogens causing
whooping cough or
whooping cough-like disease and hypothesized to have evolved from environmental non-classical bordetellae.
Bordetella infections have increased globally driving the need to better understand these pathogens for the development of new treatments and
vaccines. One unexplored component in Bordetella is the role of
serine,
threonine and
tyrosine phosphorylation. Therefore, this study characterized the phosphoproteome of classical bordetellae and examined its potential role in Bordetella biology and virulence. Applying strict identification of localization criteria, this study identified 70 unique phosphorylated
proteins in the classical bordetellae group with a high degree of conservation. Phosphorylation was a key regulator of Bordetella metabolism with
proteins involved in gluconeogenesis, TCA cycle,
amino acid and
nucleotide synthesis significantly enriched. Three key virulence pathways were also phosphorylated including
type III secretion system,
alcaligin synthesis and the BvgAS master transcriptional regulatory system for virulence genes in Bordetella. Seven new phosphosites were identified in BvgA with 6 located in the
DNA binding domain. Of the 7, 4 were not present in non-classical bordetellae. This suggests that
serine/
threonine phosphorylation may play an important role in stabilizing/destabilizing BvgA binding to
DNA for fine-tuning of virulence gene expression and that BvgA phosphorylation may be an important factor separating classical from non-classical bordetellae. This study provides the first insight into the phosphoproteome of classical Bordetella species and the role that Ser/Thr/Tyr phosphorylation may play in Bordetella biology and virulence.