BORDETELLA PERTUSSIS CAN BE MOTILE AND EXPRESS FLAGELLA-LIKE STRUCTURES

HOFFMAN, CASANDRA L; FERNANDEZ, JULIETA; HEWLETT, ERIK L; SISTI, FEDERICO; DAMRON, FH; ZACCA, FEDERICO; WONG, TING

Bruselas

Simposio; 12th International Symposium on Bordetella; 2019

Bordetella Society

Bordetella bronchiseptica encodes and expresses a flagellar apparatus. In contrast, Bordetella pertussis, the causative agent of whooping cough, has historically been described as a non-motile and nonflagellated organism. The previous statements that B. pertussis was a non-motile organism were consistent with a stop codon located in the flagellar biosynthesis gene, flhA, discovered when the B. pertussis Tohama I genome was sequenced and analyzed in 2003. The stop codon has subsequently been found in all annotated genomes. Parkhill et al. also showed, however, that B. pertussis encodes all genetic material required for flagellar synthesis and function. We and others have determined by varioustranscriptomic analyses that these flagellar genes are differentially regulated in a variety of B. pertussis growth conditons. In light of these data, we tested for B. pertussis motility and found that both laboratory-adapted strains and clinical isolates, can be motile. Upon isolation of motile B. pertussis, wediscovered flagella-like structures on the surface of the bacteria and have shown the motile bacteria express flagellin protein (FliC). B. pertussis motility appears to occur primarily in the Bvg(-) phase, consistent with regulation present in B. bronchiseptica. Motility can also be induced by the presence of 10% fetal bovine serum. The observations demonstrate that B. pertussis can express flagella-like structures, and although it remains to be determined if B. pertussis express flagella during infection or ifmotility and/or flagella play roles during the cycle of infection and transmission, it is clear that these data warrant further investigation.