Editing Streptococcus pneumoniae (section)

==Interaction with ''Haemophilus influenzae''==
Historically, ''[[Haemophilus influenzae]]''  has been a significant cause of infection, and both ''H. influenzae'' and ''S. pneumoniae'' can be found in the human upper respiratory system. A study of competition ''[[in vitro]]'' revealed  ''S. pneumoniae'' overpowered ''H. influenzae'' by attacking it with  [[hydrogen peroxide]].<ref>{{cite journal |author=Pericone, Christopher D. |author2=Overweg, Karin |author3=Hermans, Peter W. M. |author4=Weiser, Jeffrey N. |title=Inhibitory and Bactericidal Effects of Hydrogen Peroxide Production by Streptococcus pneumoniae on Other Inhabitants of the Upper Respiratory Tract |journal=[[Infection and Immunity|Infect Immun]] |volume=68 |issue=7 |pages=3990–3997 |year=2000 |pmid=10858213 |doi=10.1128/IAI.68.7.3990-3997.2000 |pmc=101678}}</ref> There is also evidence that ''S. pneumoniae'' uses hydrogen peroxide as a virulence factor.<ref>{{cite journal |author=Mraheil, MA. |title=Dual Role of Hydrogen Peroxide as an Oxidant in Pneumococcal Pneumonia |journal=Antioxid Redox Signal |volume=20 |issue=34 |pages=962–978 |year=2021 |pmid=32283950|doi=10.1089/ars.2019.7964 |pmc=8035917}}</ref> However, in a study adding both bacteria to the [[nasal cavity]] of a [[mouse]] within two weeks, only ''H. influenzae'' survives; further analysis showed that [[neutrophil]]s (a type of phagocyte) exposed to dead ''H. influenzae'' were more aggressive in attacking ''S. pneumoniae''.<ref name="PLosPathog2006-Lysenko">{{cite journal | vauthors=Lysenko ES, Ratner AJ, Nelson AL, Weiser JN | title=The Role of Innate Immune Responses in the Outcome of Interspecies Competition for Colonization of Mucosal Surfaces | journal=[[PLOS Pathogens|PLOS Pathog]] | year=2005 | pages=e1 | volume=1 | issue=1 | pmid=16201010 | doi=10.1371/journal.ppat.0010001 | pmc=1238736 | doi-access=free }} [https://archive.today/20130113064742/http://pathogens.plosjournals.org/perlserv/?request=get-document&doi=%2310.1371/journal.ppat.0010001#10.1371/journal.ppat.0010001 Full text]</ref>