Comparative proteomic analysis of Neisseria meningitidis wildtype and dprA null mutant strains links DNA processing to pilus biogenesis

ABSTRACT: DNA processing chain A (DprA) is a DNA binding protein which is ubiquitous in bacteria and required for DNA transformation. However, the interaction of DprA with competence proteins and recombination is poorly understood. Therefore, the proteomes of whole Neisseria meningitidis (Nm) wildtype and dprA mutant cells were compared. Such a comparative proteomic analysis increases our understanding of the interactions of DprA with other Nm components, and may elucidate its potential role beyond DNA processing in transformation. Using label-free quantitative proteomics, a total of 1057 unique Nm proteins were identified out of which 100 were quantified as differentially abundant (P ≤ 0.05 and fold change ≥ |2|) in the dprA null mutant. Proteins involved in homologous recombination (RecA, UvrD and HolA), pilus biogenesis (PilG, PilT1, PilT2, PilM, PilO, PilQ, PilF and PilE), and cell division, including core energy metabolism and response to oxidative stress were downregulated in dprA null mutant Nm. Immunoblotting was employed to validate the differences observed in two selected proteins. The analysis revealed reduced amounts of PilG in the dprA null mutant and reduced amounts of DprA in the Nm pilG null mutant. In conclusion, DprA interacts with proteins essential for Nm DNA recombination in transformation, pilus biogenesis and other functions associated with the inner membrane. Inverse downregulation of Nm DprA and PilG expression in the corresponding mutants indicate a link between DNA processing and pilus biogenesis demonstrated for the first time.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Neisseria Meningitidis Serogroup B

TISSUE(S): Cell Lysate

DISEASE(S): Bacterial Meningitis

SUBMITTER: Shewit Kalayou  

LAB HEAD: Prof Tone Tønjum

PROVIDER: PXD006121 | Pride | 2017-04-26

REPOSITORIES: Pride