Abstract
The Helicobacter pylori protein NapA has been identified as a homologue of the Escherichia coli protein Dps. It is shown in this study that, like Dps, NapA is produced maximally in stationary phase cells and contributes to the ability of H. pylori to survive under oxidative stress conditions. Moreover, NapA co-localizes with the nuclear material, suggesting that it can interact with DNA in vivo. Furthermore, it is demonstrated that repression of NapA production by iron starvation was not so pronounced in a H. pylori fur mutant, suggesting that the ferric uptake regulator (Fur) is involved in napA regulation, and a potential fur box by which this control could be mediated is identified. This finding is consistent with the regulation of iron-binding proteins by Fur and also the modulation of Fur during oxidative stress, thus allowing NapA levels to be increased in the environmental conditions under which its ability to protect DNA from attack by toxic free radicals is most beneficial to the cell.
MeSH Terms
Bacterial Proteins/biosynthesis,genetics,physiology
Base Sequence
DNA, Bacterial/chemistry,metabolism
Electrophoresis, Polyacrylamide Gel
Escherichia coli/genetics,metabolism
Helicobacter pylori/genetics,growth & development,metabolism
Iron/metabolism
Microscopy, Fluorescence
Microscopy, Phase-Contrast
Molecular Sequence Data
Mutation
Oxidative Stress
Recombinant Proteins/biosynthesis,genetics,metabolism
Repressor Proteins/physiology
Sequence Alignment
Chemicals
Bacterial Proteins
DNA, Bacterial
Recombinant Proteins
Repressor Proteins
ferric uptake regulating proteins, bacterial
neutrophil-activating protein A, Helicobacter pylori
Iron
Authors & Affiliations
6 authors, click to expand affiliations / ORCID
Cooksley Clare
Institute of Infections and Immunity, Queen's Medical Centre, C-floor West Block, Nottingham NG7 2UH, UK 2Division of Gastroenterology, University Hospital, Nottingham NG7 2UH, UK 3School of Pharmaceutical Sciences, Nottingham University, Nottingham NG7 2RD, UK#dReceived 10 September 2002 Accepted 21 January 2003.
Jenks Peter J
Institute of Infections and Immunity, Queen's Medical Centre, C-floor West Block, Nottingham NG7 2UH, UK 2Division of Gastroenterology, University Hospital, Nottingham NG7 2UH, UK 3School of Pharmaceutical Sciences, Nottingham University, Nottingham NG7 2RD, UK#dReceived 10 September 2002 Accepted 21 January 2003.
Green Andrew
Institute of Infections and Immunity, Queen's Medical Centre, C-floor West Block, Nottingham NG7 2UH, UK 2Division of Gastroenterology, University Hospital, Nottingham NG7 2UH, UK 3School of Pharmaceutical Sciences, Nottingham University, Nottingham NG7 2RD, UK#dReceived 10 September 2002 Accepted 21 January 2003.
Cockayne Alan
Institute of Infections and Immunity, Queen's Medical Centre, C-floor West Block, Nottingham NG7 2UH, UK 2Division of Gastroenterology, University Hospital, Nottingham NG7 2UH, UK 3School of Pharmaceutical Sciences, Nottingham University, Nottingham NG7 2RD, UK#dReceived 10 September 2002 Accepted 21 January 2003.
Logan Robert P H
Institute of Infections and Immunity, Queen's Medical Centre, C-floor West Block, Nottingham NG7 2UH, UK 2Division of Gastroenterology, University Hospital, Nottingham NG7 2UH, UK 3School of Pharmaceutical Sciences, Nottingham University, Nottingham NG7 2RD, UK#dReceived 10 September 2002 Accepted 21 January 2003.
Hardie Kim R
Institute of Infections and Immunity, Queen's Medical Centre, C-floor West Block, Nottingham NG7 2UH, UK 2Division of Gastroenterology, University Hospital, Nottingham NG7 2UH, UK 3School of Pharmaceutical Sciences, Nottingham University, Nottingham NG7 2RD, UK#dReceived 10 September 2002 Accepted 21 January 2003.
