Free Responses Concepts

How do bacterial amyloids promote Parkinson’s Disease?

a-syn is produced int he gut, E. coli produce amyloid proteins that interact with a-syn, this interaction triggers a-syn misfolding and aggregation, high e. coli population induces gut membrane inflammation and leakage, a-syn aggregates move from the gut to the brain through the vagus nerve, a-syn aggregates seed in the brain and form toxis clusters called “Lewy bodies”

Describe the cross-communication between Pseudomonas aeruginosa and Aspergillus during infection in patients with cystic fibrosis

Pseudomonas aeruginosa and Aspergillus fumigatus use cross-kingdom quorum sensing, in which P. aeruginosa produces autoinducer signaling molecules that interact with Aspergillus as it germinates and forms invasive hyphae in the thick mucus of cystic fibrosis airways. This communication stabilizes a robust polymicrobial biofilm, promoting immune evasion, tissue colonization, and tissue destruction and ultimately worsening the patient’s clinical prognosis.

Describe cross-communication between Lactobacillus and Candida albicans during vaginal health and after antibiotic treatment

During high vaginal health, Lactobacillus produces AI-2 which blocks candida filamentation and induces commensalism, but after antibiotic treatment, Lactobacillus dies and can’t produce AI-2 anymore, so candida colonizes and causes inflammation and infection

Candida Albicans communication

Low fungal cell density, High tyrosol and low farnesol, Induction of attachment and filamentation, Fungal biofilm formation, High fungal cell density, High farnesol and low tyrosol, Induction of dispersion, cell death, and repress biofilm

Steps of biofilm formation

Reversible attachment, Colonization, High EPS production, Biofilm formation, Reduction in EPS production, Degradation of EPS and increase of surfactant production, Microbial dispersion

Quorum Sensing Steps

LuxI produces AI, AI is released outside of the cell, AIs get diluted outside of the cell, All bacterial cells produce AIs, increasing their concentration in the environments, Concentration of AIs increased inside of the cell, AIs bind to LuxR, LuxR becomes active, Activated LuxR binds to the promoter, promoting expression of LuxI, Luciferase, and LuxR, creating a positive feedback loop

Clostridium difficile infection

antibiotic use disturbs gut microbiota, c. difficile spore enter, spore germination and growth, toxin production and inflammation

How is host–microbiome crosstalk affected by ecological vacuum?

loss of SCFAs, which leads to increased Gut permeability and hyper-inflmmation and immune dysregulation

How is the gut–brain axis affected by ecological vacuum?

loss of psychobiotic metabolites leads to altered neurotransmitter production and vagus nerve disruption