Flow Cytometry and Automated Microscopy Integration for Phagocytic Analysis of Hypervirulent Klebsiella pneumoniae in Dictyostelium discoideum.

This chapter introduces protocols for culturing and maintaining Dictyostelium discoideum and methods for conducting virulence assays in this organism to study bacterial pathogenicity. It outlines advanced techniques, such as automated microscopy and flow cytometry, for detailed cellular analysis and traditional microbiological approaches. These comprehensive protocols will enable researchers to probe the virulence factors of pathogens like Klebsiella pneumoniae and to elucidate the details of host-pathogen interactions within a cost-effective and adaptable laboratory framework.

Zebrafish Larvae Microinjection and Automated Fluorescence Microscopy for Studying Klebsiella pneumoniae Infection and the Host Immune Response.

Studying host-pathogen interactions is essential for understanding infectious diseases and developing possible treatments, especially for priority pathogens with increased virulence and antibiotic resistance, such as Klebsiella pneumoniae. Over time, this subject has been approached from different perspectives, often using mammal host models and invasive endpoint measurements (e.g.

Carbapenem-resistant hypervirulent ST23 Klebsiella pneumoniae with a highly transmissible dual-carbapenemase plasmid in Chile.

Background: The convergence of hypervirulence and carbapenem resistance in the bacterial pathogen Klebsiella pneumoniae represents a critical global health concern. Hypervirulent K. pneumoniae (hvKp) strains, frequently from sequence type 23 (ST23) and having a K1 capsule, have been associated with severe community-acquired invasive infections.

Inorganic Polyphosphate Affects Biofilm Assembly, Capsule Formation, and Virulence of Hypervirulent ST23 .

The emergence of hypervirulent (hvKP) strains poses a significant threat to public health due to high mortality rates and propensity to cause severe community-acquired infections in healthy individuals. The ability to form biofilms and produce a protective capsule contributes to its enhanced virulence and is a significant challenge to effective antibiotic treatment. Polyphosphate kinase 1 (PPK1) is an enzyme responsible for inorganic polyphosphate synthesis and plays a vital role in regulating various physiological processes in bacteria.

The Green Tea Polyphenol Epigallocatechin-Gallate (EGCG) Interferes with Microcin E492 Amyloid Formation.

Microcin E492 (MccE492) is an antimicrobial peptide and proposed virulence factor produced by some strains, which, under certain conditions, form amyloid fibers, leading to the loss of its antibacterial activity. Although this protein has been characterized as a model functional amyloid, the secondary structure transitions behind its formation, and the possible effect of molecules that inhibit this process, have not been investigated. In this study, we examined the ability of the green tea flavonoid epigallocatechin gallate (EGCG) to interfere with MccE492 amyloid formation.