Recombinant expression and characterization of a lysozyme from the midgut of Triatoma brasiliensis (Hemiptera,Reduviidae) in comparison with intestinal muramidase activity

Insect c‐type lysozymes are antibacterial proteins that are synthesized in different organs with high activity against Gram‐positive bacteria. Because lysozymes possess muramidase activity, they also play an important role in the digestion of bacteria in Diptera. Triatomines express lysozyme‐encoding genes constitutively in the anterior region (cardia and stomach) of the midgut and the fat body after injection of bacteria into the haemocoel. The present study describes the overexpression of the Triatoma brasiliensis lysozyme 1 (lys1) in Escherichia coli. Recombinant T. brasiliensis Lys1 (TbLys1) is purified after solubilization of the inclusion bodies. The protein refolds successfully, showing muramidase activity against Micrococcus lysodeikticus lyophilized cells, after enterokinase cleavage of its thioredoxin fusion protein. In in‐gel zymograms and turbidimetric liquid assays TbLys1 is broadly active under alkaline and acid conditions, indicating a possible digestive function in the two physiologically different midgut regions of the bug: the stomach and small intestine. Muramidase activity is shown in the stomach and small intestine content of unfed bugs and bugs at different days after feeding, respectively. Western blot analysis identifies TbLys1 as lysozyme.     

Effects of photoperiod and temperature on the development of Bonagota cranaodes

Abstract.  The Brazilian apple leafroller, Bonagota cranaodes (Meyrick) (Lepidoptera: Tortricidae) is reared in the laboratory under a long-day (LD 14 : 10 h) and a short-day (LD 7 : 17 h) photoperiod at 22 °C, and under two different temperatures (10–13 °C and 21–22 °C). The development time from larval to adult eclosion do not differ between the two photoperiods, but did between the two temperature regimes. However, the larvae do not enter diapause, even under short day conditions and low temperatures. The number of adults obtained does not differ with temperature and light conditions. Field captures with pheromone traps show that Brazilian apple leafroller occurs in apple orchards throughout the year and the population densities are lower in winter. Accordingly, control measures should be taken during the off-season.     

Contrasting patterns of population structure in the montane caddisflies Hydropsyche tenuis and Drusus discolor in the Central European highlands

1. In this study, we compared mitochondrial sequence data (cytochrome oxidase I) to infer the population structure of the two montane caddisflies Hydropsyche tenuis and Drusus discolor. The two species are contrasting examples of montane aquatic insects with insular distributions: D. discolor is restricted to altitudes above 600 m, H. tenuis is limited to the same mountain ranges in Central Europe but inhabits lower altitudes. 2. In particular, we ask whether these two species with similar regional distributions show similar patterns of population structure and haplotype diversity, and whether any differences can be attributed to population history and/or autecology. 3. To determine the population structure of both species, we applied conventional population genetics analyses to mitochondrial sequence data. We collected and sampled 121 specimens of H. tenuis from 29 sites in 10 different regions of the Central European highlands and 138 individuals of D. discolor from 40 sites in 11 different regions. 4. Nine unique haplotypes were identified for H. tenuis and 34 for D. discolor. There were eight variable positions in H. tenuis and 41 in D. discolor. The maximum difference between haplotypes was 0.8% (4 bp) for H. tenuis and 4.2% (21 bp) for D. discolor. We observed haplotype overlap between geographic regions for both species. Analysis of molecular variance showed that two‐thirds of the total variance in H. tenuis was found among regions while in D. discolor, a larger portion of variance was found within regions and populations due to a higher number of haplotypes observed within regions. Mantel test showed a significant relationship between genetic and geographic distance in D. discolor, but no significant relationship in H. tenuis. 5. Our analyses show that, despite their very similar overall distribution pattern in Europe, the two species exhibit distinct population structures, which may reflect differences in phylogeographic history, dispersal capabilities, habitat specifity or within‐region geographic occurrence.     

Systematic notes on some Antarctic Ascophora (Bryozoa, Cheilostomata)

Nine new species of ascophoran cheilostome Bryozoa are described from Antarctic localities. Five species are considered to be new to science ( Smittina favulosa, Smittina diffidentia, Smittoidea pugiuncula, Escharella mamillata, Fenestrulina antarctica ), while four others have been previously recorded under other names ( Smittoidea malleata, Escharella watersi, Lacerna watersi, Hippothoa belgica ). Escharella crozetensis Waters, formerly recorded from Antarctica, is considered to be limited to the Kerguelen region of the South Indian Ocean.     

Analysis of Pneumocystis carinii Cyst Wall I. Evidence for an Outer Surface Membrane

ABSTRACT. It has long been thought that the cyst form of Pneumocystis carinii , which can resist host defenses and antimicrobial drugs, is responsible for relapses of P. carinii pneumonia. The thick wall of the cyst is immunogenic and rich in glucosyl/mannosyl and N-acetyl-D-glucosamine residues. In this study we have demonstrated the presence of a hitherto unreported outer membrane in the cyst wall of P. carinii . This membrane was detected by a combination of techniques, including transmission electron microscopy, freeze-fracture electron microscopy, and membrane labeling with fluorescent lipid analogs following treatment of P. carinii cysts from infected rats for 30 min with Zymolyase, a β-1–3 glucanase. As in gram-negative bacteria and blue-green algae, this 2nd membrane may have an important role in osmoregulation and nutrient utilization; it may also mediate the interaction of P. carinii with its host and serve as a target for drug therapy.     

Studies on the local dispersal of the New Zealand flatworm, a predator of earthworms, in Edinburgh between 1993 and 1999

The flatworm Artioposthia triangulata was found, from studies using weighted down plastic sheeting, to move predominantly through the soil rather than over it and to use earthworm burrows. Under compost‐filled plastic sacks the flatworm was most active at night although its numbers were similar to those during the day. The transfer of specimens into an area covered with weighted plastic sheeting had no lasting effect on their numbers. The flatworm was regularly removed over 6 years from under paving stones, sheets of newspaper and cardboard placed on the ground in a garden. The rise and fall of the numbers of the flatworm under this debris suggest a predator‐prey periodicity between the flatworm and earthworms of 3 years.     

Cryptic diversity in the long‐horn moth Nemophora degeerella (Lepidoptera: Adelidae) revealed by morphology,DNA barcodes and genome‐wide ddRAD‐seq data

The growth of DNA barcode libraries has now revealed many cases of potentially cryptic diversity in various groups of generally well‐studied European Lepidoptera. In this paper, we revise a complex of cryptic species, which were formerly all classified as one species, Nemophora degeerella (Linnaeus, 1758). We found that this complex consists of three taxa: N. degeerella (Linnaeus, 1758), which is widely distributed across temperate Europe north of the Alps, from Portugal to Finland, Central Russia and Ukraine; N. scopolii sp.n. , which inhabits central and southern Europe (Slovakia, southern Germany, Austria, Slovenia and Italy); and N. deceptoriella sp.n. from the Caucasus (Russia and Georgia). These species are separated by subtle but stable external morphological characters (forewing size and pattern, relative size of the labial palpus, scapus and compound eyes) and divergent cytochrome c oxidase subunit I (COI) lineages, with at least one geographical region (Austria to southern Germany and Slovakia) where two of these species (N. degeerella and N. scopolii) co‐occur. The characters of the male genitalia and four nuclear markers (CAD, EF‐1a, MDH and MDH; available for two of the three taxa) did not support the separation of the taxa, but data derived from 1363 and 390 restriction‐site associated DNA sequencing (RAD) loci (altogether consisting of 259 311 and 71 778 bp) of four specimens of each N. degeerella and N. scopolii, which were collected mostly from the contact zone strongly supported their distinctiveness as independent lineages. Our study is one of the still quite few cases where morphological and COI analyses are supplemented with nuclear data, and one of the very first cases where next‐generation sequencing based on double‐digest RAD sequencing (ddRAD‐seq) methods have been applied to address taxonomic questions in insects. This published work has been registered in ZooBank: http://zoobank.org/urn:lsid:zoobank.org:pub:FBA1953A‐412E‐4395‐BB36‐B650621DD0D0 .