Rapid and reliable discrimination between Shigella species and Escherichia coli using MALDI-TOF mass spectrometry

E. coli-. Shigella species are a cryptic group of bacteria in which the Shigella species are distributed within the phylogenetic tree of E. coli. The nomenclature is historically based and the discrimination of these genera developed as a result of the epidemiological need to identify the cause of shigellosis, a severe disease caused by Shigella...

Novel role of the antimicrobial peptide LL-37 in the protection of neutrophil extracellular Traps against degradation by bacterial nucleases

Neutrophil extracellular traps (NETs) have been described as a fundamental innate immune defence mechanism. They consist of a nuclear DNA backbone associated with different antimicrobial peptides (AMPs) which are able to engulf and kill pathogens. The AMP LL-37, a member of the cathelicidin family, is highly present in NETs. However, the...

The antimicrobial peptide LL-37 facilitates the formation of neutrophil extracellular traps

NETs (neutrophil extracellular traps) have been described as a fundamental innate immune defence mechanism. Duringformation of NETs, the nuclear membrane is disrupted by an asyet unknown mechanism. In the present study we investigated the role of human cathelicidin LL-37 in nuclear membrane disruption and formation of NETs. Immunofluorescence...

A cathelicidin-2-derived peptide effectively impairs Staphylococcus epidermidis biofilms

Staphylococcus epidermidis is a major cause of nosocomial infections owing to its ability to form biofilms on the surface of medical devices. Biofilms are surface-adhered bacterial communities. In mature biofilms these communities are encased in an extracellular matrix composed of bacterial polysaccharides, proteins and DNA. The antibiotic...

Avian cathelicidins: Paradigms for the development of anti-infectives

The broad-spectrum defense system based on host defense peptides (HDPs) is evolutionary very old and many invertebrates rely on this system for protection from bacterial infections. However, in vertebrates the system remained important in spite of the superposition of a very sophisticated adaptive immune system. The cathelicidins comprise a...

Improved proteolytic stability of chicken cathelicidin-2 derived peptides by d-amino acid substitutions and cyclization

A truncated version of host defense peptide chicken cathelicidin-2, C1-15, possesses potent, broad spectrum antibacterial activity. A variant of this peptide, F2,5,12W, which contains 3 phenylalanine to tryptophan substitutions, possesses improved antibacterial activity and lipopolysaccharide (LPS) neutralizing activity compared to C1-15. In...

Development of cathelicidin-derived peptides for the treatment of infectious diseases

Chicken cathelicidin-2-derived peptides with enhanced immunomodulatory and antibacterial activities against biological warfare agents

Host defence peptides (HDPs) are considered to be excellent candidates for the development of novel therapeutic agents. Recently, it was demonstrated that the peptide C1-15, an N-terminal segment of chicken HDP cathelicidin-2, exhibits potent antibacterial activity while lacking cytotoxicity towards eukaryotic cells. In the present study, we...

Identification of chicken cathelicidin-2 core elements involved in antibacterial and immunomodulatory activities

Chicken host defense peptide cathelicidin-2 (CATH-2) is known to exert antimicrobial and immunomodulatory activities and consists of two α-helices connected by a hinge region. Here we report the biological properties of the separate α-helical segments and the importance of the proline residue in the hinge region. Substitution of proline-14 in...

C1-15 derived antimicrobial peptides for therapeutic applications against BWA

Structure-function relationship of the human antimicrobial peptide LL-37 and LL-37 fragments in the modulation of TLR responses

Cathelicidins are effector molecules of the innate host defense system that establish an antimicrobial barrier at epithelial interfaces. The human cathelicidin LL-37, in addition to its antimicrobial activity, also exhibits immunomodulatory effects, such as inhibition of pro-inflammatory responses to bacterial LPS in human monocytic cells. In...