Related Experiment Video
Updated: Jun 23, 2026
10:03
Inducing Meningococcal Meningitis Serogroup C in Mice via Intracisternal Delivery
Published on: November 5, 2019
A two-component system is required for colonization of host cells by meningococcus
Anne Jamet1,2, Clotilde Rousseau1,2, Jean-Benoît Monfort1,2
1Université Paris Descartes, Faculté de Médecine René Descartes, F-75006 Paris, France.
Microbiology (Reading, England)
|April 25, 2009
Summary
Neisseria meningitidis uses a two-component system (TCS) to adapt to host cells. This PhoQ/PhoP TCS regulates genes essential for bacterial colonization and growth on human cells.
Area of Science:
- Microbiology
- Bacterial Pathogenesis
- Molecular Biology
Background:
- Bacteria utilize two-component systems (TCSs) for environmental adaptation.
- Host cell colonization is crucial for pathogens like Neisseria meningitidis.
- The PhoQ/PhoP TCS in N. meningitidis is a known signal transduction pathway.
Purpose of the Study:
- To investigate the role of the PhoQ/PhoP TCS in N. meningitidis adaptation to host cell growth.
- To determine if this TCS is involved in the colonization process.
Main Methods:
- Created a mutant lacking the sensor component of the PhoQ/PhoP TCS.
- Assessed the mutant's ability to grow on host cells.
- Analyzed gene expression changes controlled by the TCS.
Main Results:
- The PhoQ/PhoP TCS is essential for N. meningitidis to grow on host cells.
- TCS expression is regulated by cell contact.
- The TCS controls the REP2 regulon, vital for host cell adaptation.
Conclusions:
- The PhoQ/PhoP TCS plays a significant role in N. meningitidis adaptation to host cell colonization.
- This TCS links environmental sensing to gene regulation for pathogenesis.
Related Concept Videos
01:26Bacterial Meningitis II: Pathophysiology
Bacterial meningitis typically begins when pathogens such as Neisseria meningitidis and Streptococcus pneumoniae colonize the nasopharynx and invade the bloodstream. This process is facilitated by bacterial virulence factors, such as polysaccharide capsules, which resist phagocytosis and complement-mediated killing. Less commonly, bacteria reach the central nervous system via contiguous spread from infections like otitis media or sinusitis, through congenital or acquired dural defects, or...
01:24Bacterial Meningitis
Bacterial meningitis is a severe infectious disease involving inflammation of the meninges, the protective membranes surrounding the brain and spinal cord. It occurs when pathogenic bacteria cross the blood–brain barrier and enter the cerebrospinal fluid. Common causative organisms include Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae type b, Listeria monocytogenes, and Escherichia coli K1. The exact route of entry varies by pathogen and host condition.Routes of Entry...
01:22Bacterial Meningitis I: Introduction
Bacterial meningitis is a severe, life-threatening inflammation of the meninges, particularly the pia mater and arachnoid mater, affecting the subarachnoid space, ventricles, and cerebrospinal fluid (CSF). If untreated, it can lead to significant neurological complications or death.Causative AgentsCommon pathogens vary with age and immune status. In adults, major organisms include Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae. Streptococcus agalactiae (group B...
01:25Colonisation of Pathogens
Pathogen colonization of host tissues is a critical step in the development of infectious diseases. Various pathogenic microorganisms, including bacteria, fungi, viruses, and protozoa, have evolved complex strategies to attach to, invade, and persist within host environments. These mechanisms enable pathogens to establish infections, evade immune responses, and resist antimicrobial treatments.Attachment to Host CellsIn bacteria, colonization typically begins with adherence to host epithelial...
01:28Regulation of Bacterial Virulence
Pathogenic bacteria employ a range of regulatory mechanisms to modulate the expression of virulence genes in response to environmental and host-derived signals. These mechanisms ensure that virulence factors are expressed only under favorable conditions, thereby optimizing infection and survival strategies.Mechanisms of Virulence RegulationKey regulatory strategies include:Two-Component Systems: These consist of a membrane-bound sensor kinase and a cytoplasmic response regulator. Environmental...
01:31Defense Against Bacterial Pathogens
The human immune system is a complex network of cells, tissues, and organs that work together to defend the body against bacterial infections. It consists of various immune cells, each playing a specific role in the defense mechanism.
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...