Lyme disease is a tick-borne, multi-systemic disease, caused by the bacterium Borrelia burgdorferi. Though antibiotics are used as a primary treatment, relapse often occurs after the discontinuation of antimicrobial agents. The reason for relapse remains unknown, however previous studies suggest the possible presence of antibiotic resistant Borrelia round bodies, persisters and attached biofilm...

Monitoring insertion and orientation of peptides in situ on cell membranes remains a challenge. To this end, we synthesized an l-amino acid (AFaa) containing a dual-fluorescence dye of the 3-hydroxyflavone family, as a side chain. In contrast to other labeling approaches using a flexible linker, the AFaa fluorophore, introduced by solid phase synthesis into desired position of a peptide, is att...

To better understand the role of surface chemical heterogeneity in natural nanoscale hydration, we study via molecular dynamics simulation the structure and thermodynamics of water confined between two protein-like surfaces. Each surface is constructed to have interactions with water corresponding to those of the putative hydrophobic surface of a melittin dimer, but is flattened rather than hav...

The venom of the European honey bee Apis mellifera is an intricate mixture of chemical compositions, including proteins, peptides, enzymes, and other small molecules. Lately, there has been growing interest in the use of melittin, due to its wide range of biological and potential therapeutic applications. Melittin, which is considered to be an antimicrobial, antitumor, and antiinflammatory pept...

Depth of bilayer penetration and effects on lipid mobility conferred by the membrane-active peptides magainin, melittin, and a hydrophobic helical sequence KKA(LA)7KK (denoted KAL), were investigated by colorimetric and time-resolved fluorescence techniques in biomimetic phospholipid/poly(diacetylene) vesicles. The experiments demonstrated that the extent of bilayer permeation and peptide local...

A novel electrochemical immunosensor based on the principles of liposome signal ampli®cation and immunochromatography has been developed for the determination of theophylline. The immunosensor is composed of two major parts including a screen-printed electrode and an immunochromatographic nitrocellulose membrane strip. On the membrane, anti-theophylline antibody is immobilized in an antibody co...

Plasma membrane (PM) and endoplasmic reticulum (ER) enriched fractions were isolated from the homogenized rat kidney. Transmission electron micrographs of PM showed empty vesicles but no granules present in the fraction. Kallikrein activity was detected in the homogenate, microsomal, and PM and ER fractions; it was most enriched in PM fraction. PM-kallikrein released a klnin, cleaved the peptid...

In this work, we used the Minimum Inhibitory Concentration (MIC) technique to evaluate the antibacterial potential of the apitoxin produced by Apis mellifera bees against the causative agents of tooth decay. Apitoxin was assayed in natura and in the commercially available form. The antibacterial actions of the main components of this apitoxin, phospholipase A2, and melittin were also assessed, ...