Protein and Peptide Letters - Volume 12, Issue 1, 2005

The first issue of Volume 12 of Protein and Peptide Letters brings many changes to our journal following a very successful 2004. First, we are pleased to welcome Anna Maria Papini as the new Editor-for-Europe. Dr. Papini replaces Robin Leatherbarrow, who served with distinction from 1997 through 2004. We also want to acknowledge the outstanding contributions of John Wade, Editor-for-Asia & Australia. Authors in tho Read More

Antimicrobial peptides (AMPs) are ubiquitous molecules as they are found in microorganisms as well as in plants, invertebrates and also vertebrates. They represent the first line of defense against pathogens acting as effector molecules of innate immunity. The emergence of resistance to commonly used antibiotics has stimulated the search for new naturally occurring bactericidal and fungicidal agents that m Read More

Antimicrobial peptides (AMPs) are part of the armament that insects have developed to fight off pathogens. Insect AMPs are typically cationic and often made of less than 100 amino acid residues. Although their structures are diverse, most of the AMPs can be assigned to a limited number of families. The most common structures are represented by peptides assuming a α-helical conformation in organic solutions or disulfide-s Read More

Plants are constantly exposed to a large array of pathogenic organisms and the survival in these conditions demands quick defense responses which include the synthesis of defense peptides and proteins with antimicrobial properties. The main groups of antimicrobial peptides found in plants are thionins, defensins and lipid transfer proteins. They constitute interesting candidates to engineer disease resistance in plants.

Reports of cationic antimicrobial peptides (CAPs) have become standard fare in research literature. But with several hundred peptides described to date, the investigator who tries to navigate the proposed models of their activity is only treated to a generous serving of incongruencies. Rather than acting in isolation as antimicrobial molecules, CAPs also may synergize with other molecules of innate immunity and modulate both Read More

Oblique orientated α-helices are highly specialised protein structural elements that penetrate membranes at a shallow angle and are used to promote membrane destabilisation by a number of protein classes. Here, the use of extended hydrophobic moment methodology shows that the amphibian extrudates, aurein 1.2 and citropin 1.1, may use oblique orientated α-helices in their antimicrobial action and that such use Read More

To facilitate microbial membrane invasion, amphiphilic α-helical antimicrobial peptides (α-AMPs) show a spatial segregation of hydrophobic and hydrophilic residues about the α-helical long axis. Here we discuss potential mechanisms by which these peptides are able to disrupt membrane structure and the structural characteristics, which are required for function.

Cationic antimicrobial peptides and proteins are among the earliest molecular effectors of the innate arm of immunity in humans and other vertebrates. This review, inspired by recent emphasis on the development of topical preventatives for sexually transmitted infections, describes antimicrobial peptides and proteins in the context of microbicide design and development. Particular emphasis is placed on the defensin Read More

Antimicrobial peptides are present in organisms spanning virtually every kingdom, and employ sophisticated mechanisms to exert rapid microbicidal action consistent with their key roles in host defense. Offsetting these mechanisms, some microbial pathogens have evolved complex countermeasures to neutralize exposure to and subvert mechanisms of antimicrobial peptides. The following discussion highlights recen Read More

β-Alanine synthase (EC 3.5.1.6) catalyzes the conversion of N-carbamyl-β-alanine to β-alanine, ammonia and CO2. The enzyme has been purified to apparent homogeneity from calf liver. The molecular size, pH optimum and substrate specificity have been determined. Sequence alignment of β-alanine synthases with N-carbamyl-D-amino acid amidohydrolase from Agrobacter sp. revealed the conservation of a catalytically impor Read More

Human neuronal tau was incubated in formaldehyde solution at low concentrations and the intensity of light scattering of tau-40 solution at 480 nm increased markedly. Then potassium iodide was used to quench the intrinsic fluorescence of tau. The fluorescent quenching constants decreased as formaldehyde concentrations increased. 8-anilino- 1-naphthalenesulfonic acid (ANS) binding assay showed that a putative hydrophobic c Read More

Here we present atomic force microscopy images of the fibrils formed by human amylin(20-29). This peptide is a fragment of the polypeptide amylin, the major proteinaceous component of amyloid deposits found in cases of type-II diabetes mellitus. Our results demonstrate that the amylin(20-29) peptide fragment forms amyloid-like fibrils that display polymorphic structures. Twisting along the axis of fibrils was often Read More

The recombinant minichaperone sht GroEL191-345 was cultivated in a 3.7 L stirred bioreactor with the high yield of 216.2 mg / L broth. In the refolding of recombinant human interferon gamma (rhuIFN-γ) inclusion bodies, more than 2-3 fold enhancement in protein mass recovery and total activity were observed in the presence of free or immobilized minichaperone to the refolding buffer.

Two hemolytic peptides were isolated from the skin secretion of the Brazilian Hylidae frog Hyla biobeba, using reversed-phase chromatographic procedures. Hylins b1 and b2 exhibit short linear polypeptide chains, a large number of hydrophobic residues, amidated C-termini and hemolytic properties. These two novel peptides are the first examples of bombinins H-like peptides isolated from anurans species not related to Bo Read More

Previously, we have cloned ccdA and its associated thiol-disulfide oxidoreductase gene, catA, in Brevibacillus choshinensis. CcdA is known to be an integral membrane protein and its associated oxidoreductase homologues are believed to be membrane anchoring proteins, both providing reducing equivalents across the membrane to control correct disulfide bond formation. Here, we found that CatA is first localized as a m Read More