Structure-Antimicrobial Activity Relationships of Recombinant Host Defence Peptides Against Drug-Resistant Bacteria

Area of Science:

• Biochemistry
• Microbiology
• Drug Discovery

Background:

• Host defence peptides (HDPs) are crucial antimicrobial agents.
• Antimicrobial resistance (AMR) necessitates novel therapeutic strategies.
• Recombinant HDPs offer a potential solution to combat resistant pathogens.

Purpose of the Study:

• To investigate the antimicrobial activity of novel recombinant HDP constructs.
• To explore structure-activity relationships of engineered HDPs against healthcare-associated infections.
• To assess the efficacy of first-generation (fused HDP-GFP) and second-generation (multidomain HDPs) antimicrobials.

Main Methods:

• Design and synthesis of recombinant HDP constructs (first and second generation).
• In vitro testing of antimicrobial activity against Gram-positive and Gram-negative bacteria.
• In silico analysis to determine structure-activity relationships.

Main Results:

• First-generation HDPs showed activity against Gram-positive bacteria primarily due to amphipathicity.
• Activity against Gram-negative bacteria was linked to the quantity and exposure of Ser and Thr amino acids.
• Second-generation HDPs' effectiveness against Gram-positive bacteria depended on domain order, with terminal positioning of bioactive domains being key.

Conclusions:

• Recombinant HDPs demonstrate significant potential as novel antimicrobial agents.
• Understanding structure-activity relationships is vital for optimizing HDP design.
• Engineered HDPs offer a promising avenue to combat AMR, with specific structural features correlating to targeted efficacy.