Absence of wing polymorphism in the arboreal, phytophagous species of some taxa of temperate Hemiptera: an hypothesis

ABSTRACT.

• 1 Most arboreal Cicadellidae (Homoptera) and the arboreal, phytophagous Heteroptera are macropterous and capable of flight.
• 2 The low incidence of flightless morphs in the above insects is compared with its frequency in the species living on low vegetation.
• 3 It is suggested that in spite of the permanence of arboreal habitats, the almost complete absence of flightless morphs in these groups of the temperate Hemiptera is related to the architectural complexity of trees.

     

Electrophoretic methods for differentiating glycolytic enzymes of mouse and human origin

Summary Methods for electrophoresis and specific staining of all of the enzymes of the glycolytic pathway are illustrated. Interspecies differences between the enzymes of moue and of human origin are readily demonstrated and are applicable to studies, in mouse-human hybrid cell clones, of linkage, chromosomal assignment, and regulation of the gene loci controlling glycolytic enzymes This study was supported by Grants 1-F03-HD 43122-01 and GM 15253 from the National Institutes of Health.     

The salivary gland secretions of a neotropical bumblebee

Summary The larval salivary gland secretions ofBombus atratus were studied with cytochemical and cytophysical methods. In the young feeding larvae a proteic filamentous secretion depicting striations perpendicular to the long axis of its fibrillary threads and exhibiting a wellordered macromolecular array was found. It appears not to differ from the silk secretion described for the fully grown larvae of an europeanBombus species. However, in the fully grown larvae ofB. atratus changes which have not yet been reported for other bees occur involving the salivary gland secretion. Two secretion types are then distinguishable. One is composed of carboxylated and sulfated acid glycosaminoglycans and glycoprotein(s) (mucous secretion), and the other has the same composition as that of the filamentous secretion of the young larvae, although differing morphologically and in terms of macromolecular alignment (flocculent secretion). The filamentous secretion is assumed to be involved inB. atratus with the spinning of the silken partitions which at a relatively early stage separate the larvae reared within a common cell from one another. The mucous and flocculent secretions will participate in the cocoons which will cover the pupating larvae. The filamentous and flocculent secretions appear to contain an -helical fibroin, glycoprotein(s) and lipoprotein(s), but not collagen-type proteins.     

Salivary digestive enzymes of the wheat bug, Eurygaster integriceps (Insecta: Hemiptera: Scutelleridae)

The digestive enzymes from salivary gland complexes (SGC) of Eurygaster integriceps, and their response to starvation and feeding were studied. Moreover, digestive amylases were partially purified and characterized by ammonium sulfate precipitation and gel filtration chromatography. The SGC are composed of two sections, the principal glands and accessory glands. The principal glands are further divided into the anterior lobes and posterior lobes. The SGC main enzyme was α-amylase, which hydrolyzed starch better than glycogen. The other carbohydrases were also present in the SGC complexes. Enzymatic activities toward mannose (α/β-mannosidases) were little in comparison to activities against glucose (α/β-glucosidases) and galactose (α/β-galactosidases), the latter being the greatest. Acid phosphatase showed higher activity than alkaline phosphatase. There was no measurable activity for lipase and aminopeptidase. Proteolytic activity was detected against general and specific protease substrates. Activities of all enzymes were increased in response to feeding in comparison to starved insects, revealing their induction and secretion in response to feeding pulse. The SGC amylases eluted in four major peaks and post-electrophoretic detection of the α-amylases demonstrated the existence of at least five isoamylases in the SGC. The physiological implication of these findings in pre-oral digestion of E. integriceps is discussed.     

Fine structure of the salivary glands of Triatoma infestans (Hemiptera: Reduviidae)

The fine structure of the salivary glands of adult Triatoma infestans (Hemiptera: Reduviidae) bugs has been analyzed. Stereomicroscopy and scanning electron microscopy showed that each insect presents a pair of salivary glands, each pair containing three distinct units (main, supplementary, and accessory) with different sizes and colors. Transmission electron microscopy demonstrated that all gland units consist of a monolayer of epithelial cells surrounding a large central lumen. The gland units are enveloped by a thick basal lamina containing bundles of muscle cells. Microvilli are present at the apical plasma membrane domain of the gland cells, thus enlarging the available membrane area for saliva secretion towards the large gland lumen, although occasionally budding vesicles could be observed among the microvilli. Cytochemical analysis showed that the salivary gland cells of T. infestans present abundant endoplasmic reticulum profiles and several lipid droplets.     

Composition and variability of the saliva of coreids in relation to phytoxicoses and other aspects of the salivary physiology of phytophagous Heteroptera

In the saciform, principal salivary glands ofMictis profana (Fabr.) (Coreidae: Heteroptera, Pentatomorpha), the contents of all lobes other than the posterior form gels consistent with their contributing to the solidifying saliva (stylet sheath); the posterior lobe secretes most if not all of a sucrose-hydrolysing enzyme that occurs in the nongelling (watery) saliva. Evidence for the occurrence of such an enzyme in the saliva of other coreids is presented. That inM. profana has a pH optimum near neutral and a substrate specificity consistent with sucrase (sucrose α-D-glucohydrolase, EC 3.2.1.48) as distinct from plant invertase (β-D-fruccofuranosidase, EC 3.2.1.26). Apart from some maltose-hydrolysing activity in the salivary glands, also consistent with sucrase, no other carbohydrases and neither proteinase nor lipase were detected. Phosphatases were found in gland extracts but not in secreted saliva. The saliva contains catechol oxidase (EC 1.10.3.1) from the accessory gland and ducts. Topical application of pilocarpine caused individualM. profana to secrete up to 58 μl watery saliva which showed continuous and independent variation of sucrase activity (up to ca 0.012 Units/μl) and pH (6–8), although high sucrase content tended to coincide with high pH. Total protein varied up to 10 μg/μl, and free amino acids up to 1.8 μg/μl leucine eq. Of the many proteins and/or protein subunits separable by electrophoresis of gland contents and saliva, four had sucrase activity, the most mobile with MW ca 66 000. TLC indicatedinter alia phenyl alanine and tyrosine, but no DOPA nor other diphenolic substrates of the catechol oxidase in the watery saliva. The soluble components of the saliva, which also has marked surfactant properties, are discussed in relation to the feeding process of coreids and the characteristic lesions they produce in their food plants.     

Comparison of pectolytic enzymes covalently bound to synthetic ion exchangers using different methods of binding

Several methods have been compared for the immobilization of a crude commercial pectolytic enzyme product (Pectofoetidin G3X) on derivatives of technical ion exchangers. The conditions were optimized for maximum retention of the enzyme activity and the efficiency of the hydrolysis of pectin solution was measured for all the immobilized enzyme preparations. The merits and drawbacks of the methods used are discussed.     

The activity of the carbon metabolism enzymes inchromatium minutissimum after long-term storage

The activity of the enzymes of the tricarboxylic acid cycle and glyoxylate shunt, as well as of some enzymes involved in carbohydrate metabolism, were determined in the purple sulfur bacteriumChromatium minutissimum either maintained by subculturing in liquid medium or stored in the lyophilized state for 36 years. In cultures stored in the lyophilized state, the activities of the key enzymes of the tricarboxylic acid cycle, glyoxylate shunt, and Embden-Meyerhof-Parnas pathway were higher, whereas the activities of glucoses-phosphate dehydrogenase, pyruvate kinase, and ribulose bisphosphate carboxylase were somewhat lower than in cultures maintained by regular transfers.     

食物致敏蛋白及其检测方法

食物过敏是威胁人类健康的一大问题,并随着环境的恶化和新食物资源的出现而趋于严重,因此受到科研工作者,政府职能部门以及消费者的关注。本文就食物来源的致敏蛋白加以分类并对其结构特点进行了概述,同时也介绍了现阶段致敏蛋白的主要检测手段。以期对食品安全有进一步的了解和认识,从而减少因食物过敏造成的危害。     

Molecular cloning of cDNAs encoding a range of digestive enzymes from a phytophagous beetle, Phaedon cochleariae

To gain better knowledge of the variety of digestive enzymes in phytophagous coleopteran pests, a sequencing screen of 76 random cDNAs from a gut library from Phaedon cochleariae larvae was performed. The screen yielded 21 cDNAs encoding amino-acid sequences homologous to known digestive enzymes, most of them were cell wall-hydrolysing enzymes. The deduced protein sequences of 7 cDNAs encoding putative α-amylase, cysteine proteinase, trypsin, chymotrypsin, cellulase, pectinase and xylanase display all the structural features that characterize these enzymes in other eukaryotic organisms. Except the α-amylase and chymotrypsin cDNAs, the other cDNAs probably derive from multigene families. The distribution of the corresponding enzymatic activities at various developmental stages of P. cochleariae was examined. α-amylase activity is present in guts of larvae and adults, proteinases are abundant in guts of larvae and adults, but scarce in eggs and larval carcasses, xylanases are present in the guts of larvae and adults, as well as in carcasses of larvae, whereas cellulase and pectinase activities are distributed in larval and adult guts, larval carcasses, and eggs. Only a minor fraction of the cellulases is secreted by microorganisms, suggesting that P. cochleariae synthesizes most of its own cell-wall hydrolysing enzymes. The physiological role of the enzymes is discussed, as well as the significance of these results for pest management strategies involving transgenic plants expressing enzyme inhibitors.     

New record of Compsidolon elaegnicola Yasunaga (Hemiptera: Miridae) from Korea

In this paper, two Korean Compsidolon species, C. salicellum (Herrich-Schaeffer) and C. elaegnicola Yasunaga, were treated. Of these, C. elaegnicola Yasunaga, 1999, which was previously known only from Japan, is reported from Korea for the first time and diagnosed. A dorsal habitus image and illustrations of the male genitalia are provided.     

Review of established and innovative detection methods for carbapenemase‐producing Gram‐negative bacteria

The minimal antibiotic options for carbapenemase‐producing Gram‐negative bacteria necessitate their rapid detection. A literature review of a variety of phenotypic and genotypic methods is presented. Advances in culture methods and screening media are still subject to long incubation hours. Biochemical methods have shorter turnaround times and higher sensitivities and specificities, but cannot differentiate between various types and variants. Spectrophotometric methods are cheap and efficient, but are uncommon in many clinical settings, while the MALDI‐TOF MS is promising for species identification, typing and resistance gene determination. Although next generation sequencing (NGS) technologies provide a better platform to detect, type and characterize carbapenem‐resistant bacteria, the different NGS platforms, the large computer memories and space needed to process and store genomic data and the nonuniformity in data analysis platforms are still a challenge. The sensitivities, specificities and turnaround times recorded in the various studies reviewed favours the use of the biochemical tests (Carba NP or Rapid Carb screen tests) for the detection of putative carbapenemase‐producing isolates. MALDI‐TOF MS and/or molecular methods like microarray, loop‐mediated isothermal amplification and real‐time multiplex PCR assays could be used for further characterization in a reference laboratory. NGS may be used for advanced epidemiological and molecular studies.     

Influence of dietary nutritional composition on caterpillar salivary enzyme activity

Caterpillars are faced with nutritional challenges when feeding on plants. In addition to harmful secondary metabolites and protein- and water-limitations, tissues may be carbohydrate-rich which may attenuate optimal caterpillar performance. Therefore, caterpillars have multiple strategies to cope with surplus carbohydrates. In this study, we raise the possibility of a pre-ingestive mechanism to metabolically deal with excess dietary sugars. Many Noctuid caterpillars secrete the labial salivary enzyme glucose oxidase (GOX), which oxidizes glucose to hydrogen peroxide and gluconate, a nutritionally unavailable carbohydrate to the insect. Beet armyworm, Spodoptera exigua, larvae were restricted to diets varying in protein to digestible carbohydrate (P:C) ratio (42p:21c; 33p:30c; 21p:42c) and total nutrient concentration (42% and 63%). High mortality and longer developmental time were observed when caterpillars were reared on the C-biased, P-poor diet (21p:42c). As the carbohydrate content of the diet increased, caterpillars egested excess glucose and a diet-dependent difference in assimilated carbohydrates and pupal biomass was not observed, even though caterpillars restricted to the C-biased diet (21p:42c) accumulated greater pupal lipid reserves. Larval labial salivary GOX activity was also diet-dependent and gluconate, the product of GOX activity, was detected in the frass. Unexpectedly, GOX activity was strongly and positively correlated with dietary protein content.     

阔颈叶蝉属一新种记述(半翅目:叶蝉科)

记述阔颈叶蝉属Drabescoides 1新种,即长臂阔颈叶蝉Drabescoides longiarmus sp.nov..新种近似于圆突阔颈叶蝉Drabescoides umbonata Shang, Zhang et Shen,2003,主要区别为:本种体形稍大,翅脉色泽较深,体背、颜面黄褐色,雄虫阳茎干背面两片状脊大且显著靠拢,尾节侧瓣三角形,具2个刺突,连索干细,臂极长,两臂夹角小,阳基侧突端部马蹄状,表面着生微齿,雌虫第7腹板后缘弧形深凹入.提供了新种的鉴别特征图.模式标本保存在贵州大学昆虫研究所.     

伊朗猎蝽科四新记录种(半翅目:猎蝽科)

记述伊朗猎蝽科Reduviidae真猎蝽亚科Harpactorinae昆虫4新记录种:争土猎蝽Coronus contrarius Reuter,1881、环瑞猎蝽Rhynocons annulatus(Linnaeus,1758)、红胸瑞猎蛴Rhynocoris rubrogularis (Horvfith,1880)及沙地枯猎蝽Vachiria deserta(Becker,1867).     

The shieldbug genus Parastrachia and its position within the Pentatomoidea (Insecta: Hemiptera)

A new hemipteran subfamily, Parastrachiinae , is proposed in the Cydnidae for the single genus Parastrachia Distant 1883. There are two included species, P. japonensis (Scott 1880) and P. nagaensis Distant 1908. The morphology, relationships, and taxonomic history of Parastrachia are discussed     

Repetitive mating and female fitness in Dysdercus cardinalis (Hemiptera: Pyrrhocoridae)

Using three mating-treatment groups–pairing with a male for life, pairing with a male from adult emergence to first oviposition, and no pairing (virgin)–of Dysdercus cardinalis females in a laboratory study, the following results were obtained. Most of the virgin females did not lay eggs; those that did oviposited for the first time at a considerably older age than females in the other two groups. In a lifetime, females pairing with a male for life and those pairing with a male up to first oviposition produced essentially the same number of eggs, and this was more than 3.5 times the number of eggs laid by a virgin female. Virgin females produced an average of 1.3 clutches in a lifetime, compared with about 4.5 clutches produced by females in the other two groups. Reproductive span was significantly shorter, and fecundity per day of reproductive span significantly greater, for females pairing with males for life than for those pairing with a male up to first oviposition. Age at death was significantly different amongst females in different mating-treatment groups. Virgin females had the longest life, followed by females pairing with a male up to first oviposition and females pairing with a male for life, in that order. There was a positive correlation between lifetime gross reproduction and age at death for females pairing with a male for life. There was no relationship between these two characters for females pairing with a male up to first oviposition. Both females pairing with a male for life and those pairing with a male to first oviposition exhibited a significant inverse relationship between fecundity per day and age at death. The results obtained indicate that (1) mating is a prerequisite for normal gonadal activity in Dysdercus cardinalis , and (2) repetitive mating increases the rate of reproduction. This would reduce the mean age of parenthood which is inversely related to the intrinsic rate of increase.     

Solid-phase assay for the detection of low-abundance enzymes, and antibodies to enzymes in immune reactions, using acid sphingomyelinase as a model

The development of a solid-phase immunosorbent assay, suitable for use with enzyme antigens, is described. Acid sphingomyelinase and a mouse monoclonal anti-sphingomyelinase antibody have been used to determine optimal conditions for the assay. The assay involves immobilization of a second antibody (anti-mouse IgG) in the wells of a polyvinyl microtiter plate. Soluble immune complexes of first antibody (monoclonal anti-sphingomyelinase) and antigen (sphingomyelinase), incubated in separate vials, are then reacted in the anti-mouse IgG-coated assay wells, and the extent of the cross-reaction between antibody and antigen is measured by direct assay of enzyme retained in the well. A necessary condition of the assay is that antibody must not inhibit enzyme activity, which makes it especially suitable for monoclonal antibodies. The assay finds useful application in hybridoma fluid screening, equivalence point determination, and demonstration of cross-reacting enzyme from various tissue sources.     

破骨细胞骨吸收功能的检测方法

破骨细胞是一种多核的,具有骨吸收功能的骨组织细胞,在骨吸收过程中起着至关重要的作用.破骨细胞骨吸收功能的异常会引发一系列的临床病症,如骨质疏松症、关节置换术后假体松动、骨硬化症和牙周病变等.破骨细胞骨吸收功能的进一步研究对于各类骨疾病的防治具有重要的意义.然而破骨细胞骨吸收功能的检测方法一直以来是制约破骨细胞研究的瓶颈之一.为此,围绕破骨细胞骨吸收功能的检测方法做一综述.     

The innervation of the salivary gland of the tick,Boophilus microplus

Summary Salivary of the ixodid tick Boophilus microplus Canestrini are at least partially innervated by a branch of the pedipalpal nerve. Axons containing both large granular and smaller agranular vesicles were observed within the acini associated with all types of secretory cells. A modification of the Falk-Hillarp histochemical technique was used to demonstrate discrete areas of fluorescence within the salivary acini. It is suggested that the transmitter involved with the control of salivary activities is a catecholamine and may even be dopamine.This work formed part of a thesis submitted to the University of Cambridge for the degree of Ph.D. and was supported by a studentship from the Science Research Council. I would like to thank Drs. D.J. Beadle, M.J. Berridge and H.A. Robertson for their encouragement and advice