Open AccessThe CovS/CovR Acid Response Regulator Is Required for Intracellular Survival of Group B Streptococcus in Macrophages
Author(s) -
Nicola Cumley,
Laurence Smith,
Mark Anthony,
Robin C. May
Publication year - 2012
Publication title -
infection and immunity
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.508
H-Index - 220
eISSN - 1070-6313
pISSN - 0019-9567
DOI - 10.1128/iai.05443-11
Subject(s) - biology , streptococcus pyogenes , intracellular , regulator , microbiology and biotechnology , streptococcus , group a , streptococcaceae , group b , bacteria , genetics , gene , medicine , antibiotics , staphylococcus aureus
Group BStreptococcus (GBS) is a leading cause of neonatal meningitis and septicemia. The ability of this organism to survive inside phagocytic cells is poorly understood but thought to be an important step for the establishment of disease in the host. Here, we demonstrate that GBS shows prolonged survival within J774 macrophages and that the capacity to survive is not significantly changed across a diverse range of strains representing different serotypes, multilocus sequence types (MLST), and sites of clinical isolation. Using staining for the lysosome-associated membrane protein (LAMP) and by pharmacological inhibition of phagosome acidification, we demonstrate that streptococci reside in a phagosome and that acidification of the phagosome is required for GBS to survive intracellularly. Moreover, we show that the GBS two-component system CovS/CovR, which is the major acid response regulator in this organism, is required for survival inside the phagosome.