In this study, soil bacteria were isolated and characterized including its antimicrobial peptide. For this, soil samples were collected from agriculture lands. Soil samples were diluted and cultured in nutrient agar plates to obtain the isolated bacterial colonies. Antimicrobial peptide producers were screened by stab overlay, agar well diffusion, cross streaking and lacuna assay methods. The i...

Peptides with potent broad-spectrum antibiotic activity have been identified in many animal species. Recent investigations have demonstrated that epithelial cells are a site of antibiotic peptide expression, suggesting that these peptides contribute to host defense at mucosal surfaces. Expression of tracheal antimicrobial peptide (TAP), a member of the beta-defensin family of peptides, is induc...

There is great interest in the development of antimicrobial peptides as a potentially novel class of antimicrobial agents. Several structural determinants are responsible for the antimicrobial and cytolytic activity of antimicrobial peptides. In our study, a new synthetic peptide analog, AamAP1-Lysine from the naturally occurring scorpion venom antimicrobial peptide AamAP1, was designed by modi...

Susceptibility to bacterial pneumonia in cattle is enhanced by stressors such as transportation, weaning, and commingling, which trigger a physiologic stress response resulting in elevated levels of endogenous corticosteroids and catecholamines. To determine the effect of neuroendocrine mediators on the expression of innate defense peptides in the lung, bovine tracheal epithelial cells were exp...

A number of physicochemical characteristics have been described which contribute to the biological activity of antimicrobial peptides. This information was used to design a novel antimicrobial peptide sequence by using an intrinsically inactive membrane-associated peptide derived from the HIV glycoprotein, gp41, as a starting scaffold. This peptide corresponds to the tryptophan-rich membrane-pr...

Burkholderia thailandensis is a Gram-negative soil bacterium used as a model organism for B. pseudomallei, the causative agent of melioidosis and an organism classified category B priority pathogen and a Tier 1 select agent for its potential use as a biological weapon. Burkholderia species are reportedly "highly resistant" to antimicrobial agents, including cyclic peptide antibiotics, due to mu...

Antimicrobial peptides belonging to the phylloseptin family are mainly found in phyllomedusine frogs. These peptides not only possess potent antimicrobial activity but exhibit low toxicity against eukaryotic cells. Therefore, they are considered as promising drug candidates for a number of diseases. In a recent study, potent antimicrobial activity was correlated with the conserved structures an...

Hosts have developed diverse mechanisms to counter the pathogens they face in their natural environment. Throughout the plant and animal kingdoms, the up-regulation of antimicrobial peptides is a common response to infection. In C. elegans, infection with the natural pathogen Drechmeria coniospora leads to rapid induction of antimicrobial peptide gene expression in the epidermis. Through a larg...

Salt sensitivity of antimicrobial peptides poses a major obstacle in their development as novel antibiotics. Here we report the use of helix-capping motifs to confer salt resistance upon helical antimicrobial peptides. The helical content of the template peptide [RLLR](5) was almost completely destroyed at salt concentrations over 200 mm NaCl, leading to a 8-32-fold decrease in antimicrobial ac...

background and objective : due to the evolution of multidrug-resistant strains, screening of natural resources, especially actinomycetes, for new therapeutic agents discovery has become the interests of researchers. in this study, molecular, chemical and biological screening of soil actinomycetes was carried out in order to search for peptide-producing actinomycetes. materials and methods : 60 ...