Jelleines: a family of antimicrobial peptides from the Royal Jelly of honeybees (Apis mellifera)

Four antimicrobial peptides were purified from Royal Jelly of honeybees, by using reverse phase-HPLC and sequenced by using Q-Tof-MS/MS: PFKLSLHL-NH2 (Jelleine-I), TPFKLSLHL-NH2 (Jelleine-II), EPFKLSLHL-NH2 (Jelleine-III), and TPFKLSLH-NH2 (Jelleine-IV). The peptides were synthesized on-solid phase, purified and submitted to different biological assays: antimicrobial activity, mast cell degranulating activity and hemolysis. The Jelleines-I-III presented exclusively antimicrobial activities against yeast, Gram+ and Gram- bacteria; meanwhile, Jelleine-IV was not active in none of the assays performed. These peptides do not present any similarity with the other antimicrobial peptides from the honeybees; they are produced constitutively by the workers and secreted into Royal Jelly. (C) 2004 Elsevier B.V. All rights reserved.

Structure determination of hydroxytrypargine: A new tetrahydro-beta-carboline toxin from the venom of the spider Parawixia bistriata

A new, highly active tetrahydro-p-carboline toxin from the spider Parawixia bistriata, the most-common species of social spider occurring in Brazil, was isolated. The new toxin was identified as 1,2,3,4-tetrahydro-6-hydroxy-beta-carboline (= N-[3-(2,3,4,9-tetrahydro-6-hydroxy-1H-pyrido[3,4-b]indol-1-yl)propyl]guanidine; 3). This type of alkaloid, not common among spider toxins, was found to be the most-potent constituent of the spider's chemical weaponry to kill prey. When P bistriata catch arthropods in their web, they apparently attack their prey in groups of many individuals injecting their venoms. In vivo toxicity assays with 3 demonstrated a potent lethal effect to honeybees, giving rise to clear neurotoxic effects (paralysis) before death. The compound's toxicity (LD50 value) was determined to be ca. 8 ng/g of honeybee. The investigation of the pharmacological properties and neurotoxic actions of 3 may be used in the future for the development of new drugs to be applied for pest control in agriculture.

The venomous secrets of the web droplets from the viscid spiral of the orb-weaver spider Nephila clavipes (Araneae, Tetragnatidae)

The capture web of N. clavipes presents viscous droplets, which play important roles in web mechanics and prey capture. By using scanning and transmission electron microscopy, it was demonstrated that the web droplets are constituted of different chemical environments, provided by the existence both of an aqueous and a lipid layer, which, in turn, present a suspension of tenths of vesicles containing polypeptides and/or tipids. GC/EI-MS Analysis of the contents of these vesicles led to the identification of some saturated fatty acids, such as decanoic acid, undecanoic acid, dodecanoic acid, tetradecanoic acid, octadecanoic acid, and icosanoic acid, while other components were unsaturated fatty acids, such as (Z)-tetradec-9-enoic acid, (Z)-octadec-9-enoic acid, and (Z)-icosa-11-enoic acid; and polyunsaturated fatty acids like (9Z,12Z)-octadeca-9,12-dienoic acid, (9Z,12Z,15Z)-octadeca-9,12,15-trienoic acid, and (11Z,14Z)-icosa-11,14-dienoic acid. Toxic proteins such as calcium-activated proteinase and metalloproteinase jararhagin-like precursor were also identified by using a proteomic approach, indicating the possible involvement of these enzymes in the pre-digestion of spiders' preys web-captured. Apparently, the mixture of fatty acids are relatively toxic to insects by topical application (LD50 64.3 +/- 7.6 ng mg(-1) honeybee), while the proteins alone present no topical effect; however, when injected into the prey-insects, these proteins presented a moderate toxicity (LD50 40.3 +/- 4.8 ng mg(-1) honeybee); the mixture of fatty acids and proteins is very toxic to the preys captured by the web droplets of the viscid spiral of Nephila clavipes when topically applied on them (LD50 14.3 +/- 1.8ng mg(-1) honeybee).

Programmed cell death in the larval salivary glands of Apis mellifera (Hymenoptera, Apidae)

The morphological and histochemical features of degeneration in honeybee (Apis mellifera) salivary glands were investigated in 5th instar larvae and in the pre-pupal period. The distribution and activity patterns of acid phosphatase enzyme were also analysed. As a routine, the larval salivary glands were fixed and processed for light microscopy and transmission electron microscopy. Tissue sections were subsequently stained with haematoxylin-eosin, bromophenol blue, silver, or a variant of the critical electrolyte concentration (CEC) method. Ultrathin sections were contrasted with uranyl acetate and lead citrate. Glands were processed for the histochemical and cytochemical localization of acid phosphatase, as well as biochemical assay to detect its activity pattern. Acid phosphatase activity was histochemically detected in all the salivary glands analysed. The cytochemical results showed acid phosphatase in vesicles, Golgi apparatus and lysosomes during the secretory phase and, additionally, in autophagic structures and luminal secretion during the degenerative phase. These findings were in agreement with the biochemical assay. At the end of the 5th instar, the glandular cells had a vacuolated cytoplasm and pyknotic nuclei, and epithelial cells were shed into the glandular lumen. The transition phase from the 5th instar to the pre-pupal period was characterized by intense vacuolation of the basal cytoplasm and release of parts of the cytoplasm into the lumen by apical blebbing; these blebs contained cytoplasmic RNA, rough endoplasmic reticule and, occasionally, nuclear material. In the pre-pupal phase, the glandular epithelium showed progressive degeneration so that at the end of this phase only nuclei and remnants of the cytoplasm were observed. The nuclei were pyknotic, with peripheral chromatin and blebs. The gland remained in the haemolymph and was recycled during metamorphosis. The programmed cell death in this gland represented a morphological form intermediate between apoptosis and autophagy.

General morphology and ultrastructure of the venom apparatus and convoluted gland of the fire ant, Solenopsis saevissima

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A morphological view of the relationship between indirect flight muscle maturation and the flying needs of two species of advanced eusocial bees

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cytoskeletal organization of bee ovarian follicles during oogenesis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of the insecticide pyriproxyfen on the flight muscle differentiation of Apis mellifera (Hymenoptera, Apidae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Hymenoptera marking technique

In true social hymenopterans, such as many species of bees, wasps and all species of ants, the main characteristics are the overlapping of generations, the care with the offspring and the division of labor among the members of the colony. The first biological feature means that in a same moment there are groups of individuals, with variable ages, that execute different activities in the colony. In order to study the division of labor among the members of the colony, or to estimate the life span of these insects, or even to analyze any kind of behavior in non-social insects, it is necessary to know the exact age of each individual. For this reason, the insects must be identified soon after emergence. The identification of insects with numbers is an important technological improvement in behavioral studies, mainly in honeybee colonies. The aim of this scientific note is to describe an easy and cheaper technique for marking hymenopterans.

The chelation of metal ions by the acylpolyamine toxins from the web-spider Nephilengys cruentata: effects in the intoxication/detoxification of preys

Orb-web-spiders present a series of different strategies for prey capture, involving the use of different types of silk for web building, the use of adhesive traps in the webs, the secretion of toxic compounds to the spider's preys in the adhesive coating of the capture web and the biosynthesis of a wide range of structurally related acylpolyamine toxins in their venoms. The polyamine toxins usually block neuromuscular junctions and/or the central nervous system (CNS) of Arthropods, targeting specially the ionotropic glutamate receptors; this way these toxins are used are as chemical weapons to kill / paralyze the spider's prey. Polyamine toxins contain many azamethylene groups involved with the chelation of metal ions, which in turn can interact with the glutamate receptors, affecting the toxicity of these toxins. It was demonstrated that the chelation of Ni+2, Fe+2, Pb+2, Ca+2 and Mg+2 ions by the desalted crude venom of Nephilengys cruentata and by the synthetic toxin JSTX-3, did not cause any significant change in the toxicity of the acylpolyamine toxins to the model-prey insect (honeybees). However, it was also reported that the chelation of Zn+2 ions by the acylpolyamines potentiated the lethal / paralytic action of these toxins to the honeybees, while the chelation of Cu+2 ions caused the inverse effect. Atomic absorption spectrometry and Plasma-ICP analysis both of N.cruentata venom and honeybee's hemolymph revealed that the spider's venom concentrates Zn+2 ions, while the honeybee's hemolymph concentrates Cu+2 ions. These results are suggesting that the natural accumulation of Zn+2 ions in N. cruentata venom favors the prey catching and/or its maintenance in the web, while the natural accumulation of Cu+2 ions in prey's hemolymph minimizes the efficiency of the acylpolyamine toxins as killing/paralyzing tool.

Análise de caracteres morfológicos e comportamentais em abelhas africanizadas, caucasianas e em descendentes dos seus cruzamentos

Twetve external morphological traits and seven traits of food-gathering behavior were studied in africanized and caucasian (A. m. caucasica), bees. Discriminant analysis showed that neither the length of the fourth segment of the abdomen, nor bee weight can be considered as the traits with the highest discriminatory power between africanized and caucasian bees, with any in-bred bees. In the case of in-bred bees the discriminam traits had a lower interorbital width and time to reach the feeder. Multivariate comparisons between the data of in-bred colonies and twenty hibrid colonies, suggest dominance of the genes group of the africanized subspecies.

Acidentes por lepidópteros (larvas e adultos de mariposas): estudo dos aspectos epidemiológicos, clínicos e terapêuticos

Os autores apresentam e discutem aspectos dos acidentes causados por larvas de lepidópteros (mariposas), enfatizando as manifestações dermatológicas e a dor intensa que caracterizam estes agravos. Além disso, são apresentadas larvas de mariposas que causam manifestações extracutâneas, tais como severos distúrbios de coagulação e artropatias anquilosantes, e ainda dermatites provocadas por insetos adultos. Os principais grupos de lepidópteros causadores de acidentes em humanos são demonstrados, e as medidas terapêuticas atualizadas são discutidas. O lepidopterismo e o erucismo são acidentes comuns, e é importante que o dermatologista saiba reconhecer e tratar esse tipo de envenenamento.

Polinização entomófila em pessegueiro (Prunus persica L.)

Este experimento, realizado na região de Jaboticabal (SP), utilizou uma cultura de pêssego (Prunus persica L.), durante a sua florada com a finalidade de verificar a atuação dos insetos visitantes nas flores na produção de frutos. A concentração média de açucares no néctar e a quantidade média produzida por dia de néctar é de 27,9% e de 3,2 mg, respectivamente. O peso médio das anteras por flor foi de 1,59 mg. A abelha Apis mellifera (73%) foi o principal inseto visitante seguida da Trigona spinipes (17%) e Xylocopa sp (4%). Observou-se a presença de beija-flores (6%), coletando néctar. A freqüência máxima das abelhas A. mellifera, para coleta de néctar e pólen, ocorreu as 12 horas. O número de frutos resultantes do tratamento em que as flores recebiam as visitas foi 14% maior que no tratamento em as flores não eram visitadas. do total de frutos colhidos no tratamento coberto (sem visitas), 82% apresentaram-se perfeitos, com boa formação e simetria. No tratamento descoberto, 90,2% apresentaram-se com boa formação, havendo diferença estatística entre os dois tratamentos.

Polinização em cultura de laranja (Citrus sinensis L. Osbeck, var. Pera-Rio)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Description of an injury in a human caused by a false tocandira (Dinoponera gigantea, Perty, 1833) with a revision on folkloric, pharmacological and clinical aspects of the giant ants of the genera Paraponera and Dinoponera (sub-family Ponerinae)

A partir de um acidente causado pela picada de uma formiga falsa tocandira na mão de um pescador amador, os autores descrevem os achados clínicos locais observados, tais como edema, eritema e dor excruciante e a evolução do envenenamento, que cursou com fenômenos sistêmicos imediatos, como sudorese fria, náuseas, vômitos, mal estar, taquicardia e linfadenopatia axilar à esquerda. Após três horas, a dor intensa persistia e o paciente apresentou um episódio de hematoquesia, sem história anterior de enfermidades do trato digestivo, hematológicas ou vasculares. O uso de analgésicos (Tramal® 300 mg/dia), água quente e gelo não melhorou a dor, que arrefeceu em oito horas, tendo permanecido por cerca de 24 horas. São apresentados ainda os aspectos folclóricos, farmacológicos e clínicos relacionados às picadas de tocandiras.