Stings by insects from the Hymenoptera order are known to cause life-threatening allergic reactions and impair life quality. Despite the effectiveness of conventional vespid venom immunotherapy, more standardized and safer allergy vaccines are required and recombinant hypoallergenic variants are important clinical tools. Antigen 5 is a major allergen of vespid venoms and it was previously reported that Antigen 5 from Polybia scutellaris (Poly s 5) could be a hypoallergenic variant.
View Article and Find Full Text PDFCyclodextrin glycosyltransferases (CGTases) are important enzymes in biotechnology because of their ability to produce cyclodextrin (CD) mixtures from starch whose relative composition depends on enzyme source. A multiple alignment of 46 CGTases and Shannon entropy analysis allowed us to find differences and similarities that could be related to product specificity. Interestingly, position 179 has Gly in all the CGTases except in that from Bacillus circulans DF 9R which possesses Gln.
View Article and Find Full Text PDFStings by insects from the Hymenoptera order can cause life-threatening allergic reactions and impair life quality. Immunotherapy with venom extracts is the most extensively employed treatment to reduce morbidity and mortality, but purified and safer allergy vaccines are needed. Antigen 5 is an important allergen of vespid venoms.
View Article and Find Full Text PDFSnake venom toxicity is the consequence of a combination of peptides and proteins whose identification and characterization are of great importance to understand envenomation and develop new clinical treatments. The Elapinae subfamily includes coral snakes whose bite causes mainly neurotoxic effects which disable muscle contraction and paralyse the heart as well as inhibit respiration. However, the structure-function relationship of venom toxins has been investigated only for a few species.
View Article and Find Full Text PDFThe muscle-type nicotinic receptor has two distinguishable acetylcholine binding sites at the alpha-gamma and alpha-delta subunit interfaces; alpha-conotoxins can bind them selectively. Moreover, we previously reported that alpha-conotoxin MI can interact with Torpedo californica and Torpedo marmorata receptors showing that conotoxins can also detect receptors from different species of the same genus [L. Cortez, S.
View Article and Find Full Text PDFBovine chymosin is considered the best milk-clotting enzyme for cheese manufacture; however, the thermophilic Mucor pusillus proteinase is also used nowadays. We herein report structural aspects of the aspartyl proteinase from the local mesophilic Mucor bacilliformis strain. Sequence data indicate a high similarity degree to those of other family members.
View Article and Find Full Text PDFArch Biochem Biophys
November 2002
Vespid venoms contain Antigen 5, an important allergen whose primary structure and immunological behavior have been extensively studied from venoms of vespids of the Northern Hemisphere. We report herein structural and immunological aspects of Antigen 5 from Polybia scutellaris subspecies rioplatensis (vulgar name: camoati) found in South America. Mast cell degranulation, histamine release, and IgE induction experiments performed in mice allow us to suggest that P.
View Article and Find Full Text PDFThe muscle-type nicotinic receptor has two pharmacologically distinguishable acetylcholine binding sites at the alpha-gamma and alpha-delta subunit interfaces; alpha-conotoxins can bind them selectively. As reported, alpha-conotoxin MI has greater affinity for the site near the alpha-delta interface of the BC(3)H1 cell receptor but, in the case of the Torpedo californica receptor, displays greater affinity for that near the alpha-gamma interface. To further investigate ligand selectivity, we study the conotoxin MI-Torpedo marmorata receptor interaction.
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