Three oyster defensin variants (Cg-Defh1, Cg-Defh2, and Cg-Defm) were produced as recombinant peptides and characterized in terms of activities and mechanism of action. In agreement with their spectrum of activity almost specifically directed against Gram-positive bacteria, oyster defensins were shown here to be specific inhibitors of a bacterial biosynthesis pathway rather than mere membrane-a...

introduction: scorpion venom is a source of bioactive peptides, and some antimicrobial peptides (amps) have been found in the venom gland of scorpions. therefore, the discovery of new anti-infective agents is an essential need to overcome the problem of antibiotic resistance of clinical isolates. here, we describe three new cationic amps, including meuvap-6, meuap-18-1, and meupep34 from the ve...

The high resistance to infections in lizard wounds suggests that these reptiles possess effective antimicrobial peptides in their tissues. The present immunocytochemical study shows the cellular localization of beta-defensin 27 in tail tissues and in the blood, a defensin previously identified in the lizard Anolis carolinensis through biomolecular methods. Beta-defensin-27 immunoreactivity is o...

There is substantial interest in the identification of circulating human tumor-derived proteins in serum for the purposes of early cancer diagnosis. We have implemented an approach based on the analysis of microarray data for the identification of tumor proteins that may have utility as biomarkers in colon cancer. Expression analysis of microarray data obtained from a variety of 283 tumors and ...

Human α-defensins are potent anti-microbial peptides with the ability to neutralize bacterial and viral targets. Single alanine mutagenesis has been used to identify determinants of anti-bacterial activity and binding to bacterial proteins such as anthrax lethal factor. Similar analyses of α-defensin interactions with non-enveloped viruses are limited. We used a comprehensive set of human α-def...

Progress in molecular genetics makes possible the development of alternative disease control strategies that target the competence of mosquitoes to transmit pathogens. We tested the regulatory region of the vitellogenin (Vg) gene of Aedes aegypti for its ability to express potential antipathogen factors in transgenic mosquitoes. Hermes-mediated transformation was used to integrate a 2.1-kb Vg-p...

BACKGROUND In the past 60 years, antibiotics have been critical in the fight against infectious diseases caused by bacteria and other microbes. Development of resistance to the antibiotics is emerging as a major public health issue which has resulted in the search for new antibiotics in order to maintain a pool of effective drugs at all times. Currently, there is a great interest in cationic pe...

BACKGROUND The damaging effects of cigarette smoke on the lungs are well known in terms of cancer risks. Additional molecular changes within the lung tissue can also occur as a result of exposure to cigarette smoke. The human β-defensin (hBD) class of antimicrobial peptides is the focus of our research. In addition to antimicrobial activity, β-defensins also have immunomodulatory functions. Ove...

OBJECTIVE To determine alterations in quantities and distributions of natural antimicrobials following ischemia-reperfusion injury. We hypothesized that these compounds would be upregulated in areas of small intestine where changes in permeability and cellular disruption were likely and where protective mechanisms would be initiated. METHODS Rats with ischemia-reperfusion underwent superior m...

Hemolymph from partially fed virgin Dermacentor variabilis females was collected following Borrelia burgdorferi challenge and assayed for antimicrobial activity against Bacillus subtilis and B. burgdorferi. A small inducible cationic peptide was identified by SDS-PAGE in the hemolymph of these ticks as early as 1h post challenge. Following purification by a three-step procedure involving sequen...