Antimicrobial Peptides and Their Assemblies

Abstract

Antibiotic resistance requires alternatives to fight multi-drug resistant strains. Antimicrobial peptides (AMPs) act by disrupting or solubilizing microbial cell walls or membranes in accordance with mechanisms difficult to counteract from the microbe’s point of view. In this review, structure–activity relationships for AMPs and their assemblies are discussed, considering not only their self-assembly but also their interactions with their carriers for optimal delivery or their combinations with other complementary antimicrobials or moieties covalently bound to their chemical structure. The effect of the formulations on AMP activity is also evaluated, revealing a myriad of possibilities. Depending on the interaction forces between the AMP, the carrier, or the elements added to the formulations, AMP activity can be reduced, enhanced, or remain unaffected. Approaches protecting AMPs against proteolysis may also reduce their activity.

Emerging Cationic Nanovaccines

“…Melittin, a main component of bee venom, is a cationic amphiphilic peptide with a linear α-helix structure with antitumor, antiviral and anti-inflammatory effects in vitro and in vivo as comprehensively reviewed recently [207]. In fact, the potential of antimicrobial peptides and their assemblies shaped as NPs requires further investigations for the benefit of cancer immunotherapy [208,209]. Some probiotics such as Lactobacillus rhamnosus and Bifidobacterium longum coated with lipid membrane could be protected against loss of activity and thereby achieve better colonization in colon; subcutaneous transplant of colon cancer in mice was studied in the presence of this probiotic formulation; there were preventive and therapeutic effects that could be further improved by adding cancer nanovaccines; probiotics formulation alone efficiently reduced tumor numbers in colon whereas in combination with cancer nanovaccines improved immune responses were obtained [210].…”