Essential role of Bordetella NadC in a quinolinate salvage pathway for NAD biosynthesis.

Nicotinamide adenine dinucleotide (NAD) is produced via de novo biosynthesis pathways and by salvage or recycling routes. The classical Bordetella bacterial species are known to be auxotrophic for nicotinamide or nicotinic acid. This study confirmed that Bordetella bronchiseptica, Bordetella pertussis and Bordetella parapertussis have the recycling/salvage pathway genes pncA and pncB, for use of nicotinamide or nicotinic acid, respectively, for NAD synthesis.

Interspecies variations in Bordetella catecholamine receptor gene regulation and function.

Bordetella bronchiseptica can use catecholamines to obtain iron from transferrin and lactoferrin via uptake pathways involving the BfrA, BfrD, and BfrE outer membrane receptor proteins, and although Bordetella pertussis has the bfrD and bfrE genes, the role of these genes in iron uptake has not been demonstrated. In this study, the bfrD and bfrE genes of B. pertussis were shown to be functional in B.

Involvement of multiple distinct Bordetella receptor proteins in the utilization of iron liberated from transferrin by host catecholamine stress hormones.

Bordetella bronchiseptica is a pathogen that can acquire iron using its native alcaligin siderophore system, but can also use the catechol xenosiderophore enterobactin via the BfeA outer membrane receptor. Transcription of bfeA is positively controlled by a regulator that requires induction by enterobactin. Catecholamine hormones also induce bfeA transcription and B.

Differential expression of Bordetella pertussis iron transport system genes during infection.

Temporal expression patterns of the Bordetella pertussis alcaligin, enterobactin and haem iron acquisition systems were examined using alcA-, bfeA- and bhuR-tnpR recombinase fusion strains in a mouse respiratory infection model. The iron systems were differentially expressed in vivo, showing early induction of the alcaligin and enterobactin siderophore systems, and delayed induction of the haem system in a manner consistent with predicted changes in host iron source availability during infection. Previous mixed infection competition studies established the importance of alcaligin and haem utilization for B.