Biomedical activity and related volatile compounds of Thai honeys from three different honeybee species Puttamayutanon P., Angeli S., Thakeow P., Abraham J. and Disayathanoowat T. Department of Biology, Faculty of Science, Chiang Mai
University, Chiang Mai, Thailand This study investigated the effect of 3 factors
(floral source, honeybee species, and postcollection
processing) that influence the antibacterial activity,
free radical reduction, and other biochemical
compositions of different honey types typical of
Thailand. Honey samples from 3 honeybee species (
Apis mellifera, Apis cerana, and Apis
dorsata) were obtained from 9 floral sources
(longan, wild flower, lychee, coffee, sunflower,
sesame, bitter bush, para-rubber, and manuka as a
control) in different regions of Thailand. These
samples were evaluated for both their total and
nonperoxide antibacterial activity against 10 human
pathogens by agar incorporation technique. Honey
samples were further analyzed to evaluate the capacity
for free radical-scavenging activity, total phenolic
content, and the total flavonoid contents by the
2,2-diphenyl- 1-picrylhydrazyl assay, Folin–Ciocalteu
method, and aluminum chloride colorimetric assay,
respectively. Furthermore, the volatile organic
compounds (VOCs) of Thai honey samples were
investigated by headspace solid-phase microextraction
and gas chromatography-mass spectrometry analysis.
Findings of this study suggest a strong correlation
between floral origin and honeybee species on one
hand, and differences in %Brix, total acidity, protein
content, antimicrobial activities, free radical
reduction, phenolic, and flavonoid contents on the
other hand. Moreover, VOCs of wild and coffee honey
types were remarkably different, depending on the
floral source. Both honeys contained characteristics
of VOCs, some of which are involved in antibacterial
and antioxidant activities.
Root damage of apple plants by cockchafer larvae induces a change in volatile signals below- and above-ground Abraham J., Giacomuzzi V. and Angeli S. Faculty of Science and Technology, Free University
of Bozen-Bolzano, Bolzano, Italy Volatile organic compounds (VOCs) mediate
communication between plants and insects. Plants
under insect herbivore attack release VOCs either at
the site of attack or systemically, indicating
within-plant communication. Some of these VOCs,
which may be induced only upon herbivore attack,
recruit parasitoids and predatory insects to feed on
the attacking insects. Moreover, some plants are
able to ‘eavesdrop’ on herbivore-induced plant
volatiles (HIPVs) to prime themselves against
impending attack; such eavesdropping exemplifies
plant–plant communication. In apple orchards, the
beetle Melolontha melolontha L. (Coleoptera:
Scarabaeidae) is an important insect pest whose
larvae live and feed on roots for about 4 years. In
this study, we investigated whether the feeding
activity of M. melolonthalarvae (1) alters
the volatile profile of apple roots, (2) induces the
release of HIPVs systemically in the leaves, and (3)
whether infested plants communicate to neighbouring
non-infested conspecifics through HIPVs. To answer
these questions, we collected constitutive VOCs from
intact M9 roots as well as M. melolontha
larvae-damaged roots using a newly designed
‘rhizobox’, to collect root-released volatiles in
situ, without damaging the plant root system. We
also collected VOCs from the leaf-bearing shoots of
M9 whose roots were under attack by M.
melolontha larvae and from shoots of
neighbouring non-infested conspecifics. Gas
chromatography-mass spectrometry analysis showed
that feeding activity of M. melolontha
larvae induces the release of specific HIPVs; for
instance, camphor was found in the roots only after
larvae caused root damage. Melolontha melolontha
also induced the systemic release of methyl
salicylate and (E, E)-a-farnesene from
the leaf-bearing shoots. Methyl salicylate and (E,
E)-a-farnesene were also released by the
shoots of noninfested neighbouring conspecifics.
These phenomena indicate the induction of specific
VOCs below- and above-ground upon M. melolontha
larvae feeding on apple roots as well as plant–plant
communication in apple plants.
Multilocus genotyping of Amylostereum spp. associated with Sirex noctilio and other woodwasps from Europe reveal clonal lineage introduced to the US Castrillo L.A., Hajek A. E., Kepler R. M., Pajares J. A., Thomsen I. M., Csóka G., Zamora P., Angeli S. Department of Entomology, Cornell University,
Ithaca, USA Sirex noctilio is a woodwasp of Eurasian
origin that was inadvertently introduced to the
southern hemisphere in the 1900s and to North
America over a decade ago. Its larvae bore in Pinus
spp. and can cause significant mortality in pine
plantations. Sirex noctilio is associated
with a symbiotic white rot fungus, Amylostereum
areolatum, which females inject into trees
when they oviposit and which is required for
survival of developing larvae. We compared the
genetic diversity of A. areolatum isolated
from S. noctilio and other woodwasps
collected from Europe and from northeastern North
America to determine the origin of introduction(s)
into the United States. Multilocus genotyping of
nuclear ribosomal regions and protein coding genes
revealed two widespread multilocus genotypes
(MLGs) among the European samples, one of which is
present in the US. The other two A. areolatum
MLGs associated with S. noctilio in the US
represented unique yet very similar haplotypes,
with variation primarily in the laccase locus, and
the other loci having conserved sequences. These
latter two haplotypes were likely from
unrepresented source populations, and together
with the widespread haplotype introduced to the US
reveal multiple A. areolatum haplotypes
introduced by S. noctilio and indicate
possible multiple S. noctilio
introductions to North America from Europe. Our
results also showed a lack of fidelity between
woodwasp hosts and Amylostereum species.
We found a North American woodwasp carrying an A.
amylostereum MLG likely introduced by S.
noctilio and we report that two Urocerus
spp. specimens from Spain, previously only
reported as associated with A. chailletii,
instead carried A. areolatum in their
mycangia. These results underscore the need to
study North American siricids and their fungal
symbionts as S. noctilio continues to
spread in North America.
Development of concentrated strawberry beverage fortified with longan seed extract Sriwattana S., Phimolsiripol Y., Pongsirikul I., Utama-ang N., Surawang S., Decharatanangkoon S., Chindaluang Y., Senapa J., Wattanatchariya W., Angeli S. and Thakeow P. 1Division of Product Development Technology,
Faculty of Agro-Industry, Chiang Mai University,
Chiang Mai, Thailand Longan (Dimocarpus longan Lour.) is an
important and economic crop in northern
Thailand. Longan fruits can be consumed as fresh
or processed products, such as canned longan,
dried longan and longan in baked goods. Longan
processing often consists of removing the shell
and seeds that are then discarded. In fact,
longan seeds contain phenolic compounds, which
are antioxidants and free radical scavengers.
Therefore, in this research we aimed to extract
longan seeds (cultivar Edor) and fortify the
crude extract into a concentrated strawberry
beverage. The efficiency of two extraction
solvents, hot water (70-75°C) and ethanol (70%),
were compared. The total phenolic compounds of
the crude extracts were 41.2 ± 0.2 and 11.7 ±
0.1 mg GAE/g for hot water and ethanol
extraction, respectively. The strawberry
concentrate was produced using a
freeze-concentration process. The effect of the
number of freeze cycles on the quality of the
strawberry concentrate was also evaluated. The
concentrated strawberry produced by two freezing
cycles was selected to develop a beverage
according to the richness in vitamin C,
anthocyanin contents, and consumer acceptance.
The optimized formula of concentrated strawberry
beverage fortified with longan seed extract was
5.58% sweetener and 0.42% longan seed extract.
This drink contained 248.73 mg/100 g vitamin C,
35.6 mg/100 g anthocyanin content, and 0.17 g/L
DPPH free radical scavenging activity. An
acceptance test using a 9-point hedonic scale
showed that consumers (n=100) accepted the
concentrated product with a ‘like very much’
judgment (7.2-7.7 marks). The concentrated
strawberry beverage fortified with longan seed
extract developed here offers several health
benefits and shows potential as a commercial
product.
Behavioral and antennal responses of Spotted Wing Drosophila, Drosophila suzukii, to volatiles from fruit extracts Abraham J., Zhang A., Angeli S., Abubeker S., Michel C., Feng Y. and Rodriguez-Saona C. Faculty of Science and Technology, Free
University of Bozen-Bolzano, Italy Native to Southeast Asia, the spotted wing
drosophila, Drosophila suzukii Matsumura
(Diptera: Drosophilidae), has become a serious
pest of soft-skinned fruit crops since its
introduction into North America and Europe in
2008. Current monitoring strategies use baits
based on fermentation products; however, to
date, no fruit-based volatile blends attractive
to this fly have been identified. This is
particularly important because females are able
to cut into the epicarp of ripening fruit for
oviposition. Thus, we conducted studies to: 1)
investigate the behavioral responses of adult
D. suzukii to volatiles from blueberry,
cherry, raspberry, and strawberry fruit
extracts; 2) identify the antennally active
compounds from the most attractive among the
tested extracts (raspberry) using gas
chromatography (GC)– mass spectrometry and
coupled gas chromatography –
electroantennographic detection (GC-EAD); and 3)
test a synthetic blend containing the EAD-active
compounds identified from raspberry extract on
adult attraction. In olfactometer studies, both
female and male D. suzukii were
attracted to all four fruit extracts. The
attractiveness of the fruit extracts ranks as:
raspberry > strawberry > blueberry >
cherry. GC analyses showed that the fruit
extracts emit distinct volatile compounds. In
GC-EAD experiments, 11 raspberry extract
volatiles consistently elicited antennal
responses in D. suzukii. In choice test
bioassays, a synthetic EAD-active blend
attracted more D. suzukii than a blank
control, but was not as attractive as the
raspberry extract. To our knowledge, this is the
first report of a behaviorally and antennally
active blend of host fruit volatiles attractive
to D. suzukii, offering promising
opportunities for the development of improved
monitoring and behaviourally based management
tools.
Loss of Drosophila pheromone reverses its role in sexual communication in Drosophila suzukii Dekker T., Mansourian S., Revadi S., Ramasamy S., Lebreton S., Becher P.G., Angeli S., Rota-Stabelli O. and Anfora G. Department of Plant Protection Biology, Swedish
University of Agricultural Sciences, Alnarp,
Sweden The Drosophila pheromone cis-11-octadecenyl
acetate (cVA) is used as pheromone
throughout the melanogaster group and fulfils a
primary role in sexual and social behaviours.
Here, we found that Drosophila suzukii,
an invasive pest that oviposits in undamaged
ripe fruit, does not produce cVA. In
fact, its production site, the ejaculatory bulb,
is atrophied. Despite loss of cVA
production, its receptor, Or67d, and cognate
sensillum, T1, which are essential in cVA-mediated
behaviours, were fully functional. However, T1
expression was dramatically reduced in D.
suzukii, and the corresponding antennal
lobe glomerulus, DA1, minute. Behavioural
responses to cVA depend on the input
balance of Or67d neurons (driving cVA-mediated
behaviours) and Or65a neurons (inhibiting cVA-mediated
behaviours). Accordingly, the shifted input
balance in D. suzukii has reversed cVA's
role in sexual behaviour: perfuming D.
suzukii males with Drosophila
melanogaster equivalents of cVA strongly
reduced mating rates. cVA has thus
evolved from a generic sex pheromone to a
heterospecific signal that disrupts mating in D.
suzukii, a saltational shift, mediated
through offsetting the input balance that is
highly conserved in congeneric species. This
study underlines that dramatic changes in a
species' sensory preference can result from
rather ‘simple’ numerical shifts in underlying
neural circuits.
Olfactory responses of Drosophila suzukii females to host plant volatiles Revadi S., Vitagliano S., Rossi Stacconi M.V., Ramasamy S., Mansurian S., Carlin S., Vrhovsek U., Becher P.G., Mazzoni V., Rota-Stabelli O., Angeli S., Dekker T., Anfora G. Fondazione Edmund Mach, San Michele
all'Adige, Italy Drosophila suzukii Matsumura, an endemic pest
in southeast Asia, has invaded Europe and the
U.S.A. Unlike most of its closely related
sibling species, the serrated ovipositor of D.
suzukii permits ovipositing in undamaged fresh
fruits. In the present study, volatiles are
identified from host plants that are
potentially involved in D. suzukii host
recognition and oviposition behaviour. It is
shown that mated females are attracted to
volatiles emitted from intact fruits. The
antennally-active suite of compounds released
from the fresh fruits is identified by gas
chromatography coupled with
electroantennographic detection, as well as
gas chromatography-mass spectrometry. In
olfactometer bioassays, mated females are
significantly attracted to an
electroantennographically active volatile,
isoamyl acetate, when tested at 10 µg of
synthetic compound in a rubber septa, which
has a release rate comparable to that of fresh
fruits. In addition, a genomic survey shows
that D. suzukii not only possesses the full
repertoire of genes encoding odorant receptors
activated by isoamyl acetate in D.
melanogaster, but also that one of the genes,
OR67a, is represented by five duplicated
copies. These results indicate that D. suzukii
uses olfactory cues to select oviposition
sites. The identification of volatiles emitted
by host fruits that attract D. suzukii may aid
in the development of a selective and
efficient synthetic lure for monitoring this
pest. As a close relative of Drosophila
melanogaster, D. suzukii provides a unique
opportunity for understanding the
physiological mechanisms involved in the shift
of this species from use of rotten to ripe
fruits for oviposition.
Tissue-specific transcriptomics, chromosomal localization, and phylogeny of chemosensory and odorant binding proteins from the red flour beetle Tribolium castaneum reveal subgroup specificities for olfaction or more general functions Dippel S., Oberhofer G., Kahnt J., Gerischer L., Opitz L., Schachtner J., Stanke M., Schuetz S., Wimmer E. A. and Angeli S. Department of Developmental Biology,
University of Goettingen, Germany Background: Chemoreception is based on the
senses of smell and taste that are crucial for
animals to find new food sources, shelter, and
mates. The initial step in olfaction involves
the translocation of odorants from the
periphery through the aqueous lymph of the
olfactory sensilla to the odorant receptors
most likely by chemosensory proteins (CSPs) or
odorant binding proteins (OBPs).
Olfactory cues of mahogany trees to female Hypsipyla robusta Abraham J., Opuni-Frimpong E., Weissbecker B., Schuetz S. and Angeli S. Faculty of Science and Technology, Free University of Bozen-Bolzano, Italy The mahogany shoot borer, Hypsipyla
robusta (Moore) (Lepidoptera Pyralidae),
is a serious pest insect in the tropical
forests of Africa, Asia and Australia. This
insect causes multiple branching of young
shoots in indigenous mahogany plantations.
Gravid insects are attracted to oviposition
sites by volatile organic compounds (VOCs)
released by their hosts. Therefore, in this
study, we aimed to (i) identify and
characterise the VOCs released by the shoots
of Entandrophragma and Khaya
mahogany and (ii) to determine the
electrophysiologically active VOCs which could
influence the olfactory response of H.
robusta. Volatile samples were collected
from shoots of Entandrophragma angolense
(Welwitsch) de Candolle, Entandrophragma
utile (Dawe et Sprague) Sprague, Khaya
anthotheca (Welwitsch) de Candolle and Khaya
ivorensis Chevalier by
closed-loop-stripping-analysis. The VOCs were
identified by gas-chromatography
mass-spectrometry (GC-MS) and characterised by
comparing their retention times with those of
authentic standards. For the first time, 29
VOCs were characterised as typical of the four
mahogany species studied. The VOCs included
alcohols, aldehydes, alkanes, alkenes, esters,
ketones, monoterpenes, alcohol sesquiterpenes
and sesquiterpenes. The majority were esters
(10) and sesquiterpenes (8).
GC-MS/electroantennographic detection
experiments revealed antennal responses of the
female moth to (Z)-β-ocimene, (Z)-3-hexen-1-yl
acetate, hexan-1-ol, nonanal, (Z)-3-hexen-1-yl
butanoate, 2-ethyl hexan-1-ol, decanal,
β-caryophyllene, (Z)-3-hexen-1-yl hexanoate
and germacrene D. Dose-response experiments
with three of the compounds revealed antennal
responses at concentrations of 10-7 to 10-2.
We therefore suggest that these compounds are
olfactory cues of female H. robusta
and could be used in behaviour-based control
of H. robusta.
Effect of extraction and
concentration processes on properties of
longan syrup Surin S., Thakeow P., Seesuriyachan P., Angeli S. and Phimolsiripol, Y. Faculty of Agro-Industry, Chiang Mai University, Thailand Longan (Dimocarpus longan Lour.) syrup
is a novel liquid sweetener produced from
longan, one of the traditional and economic
fruits in the Northern of Thailand. In this
research, the effect of extraction and
concentration processes on properties of
longan syrup was investigated. There were two
extraction methods (juice extractor and
hydraulic press) and three concentration
methods (direct heating, steam heating and
vacuum evaporation). Results overall showed
that the extraction method had no significant
(p≥0.05) effect on longan syrup properties,
while concentration resulted in the quality
changes of longan syrup. Concentration using
direct heating of longan juice caused
reduction of sucrose content, and longan syrup
dark in color. The headspace volatile
compounds of longan syrup were sampled using
direct headspace technique and further
characterized using gas chromatography-mass
spectrometry. The identified volatile
compounds could be divided into two groups of
aroma characteristics which were (1) floral
aroma: 3-methybutyl acetate, (β)-ocimene and
2-phenylethyl alcohol and (2) caramel aroma:
butyraldehyde, furfural and benzaldehyde.
2-Phenylethyl alcohol, contributing to floral
odor, was retained using vacuum evaporation as
a concentration method. Result revealed that
the optimal concentration process for longan
syrup production was vacuum evaporation,
providing the highest floral volatile and
lowest caramel volatile. Sensory tests
confirmed that longan flavor of the syrup
produced from the vacuum evaporation process
had significantly higher hedonic scores than
other processes.
Ecology and management of exotic Drosophila suzukii Vitagliano S., Grassi A., Anfora G. and Angeli S. Faculty of Science and Technology, Free University of Bozen-Bolzano, Italy This paper reviews the taxonomy,
distribution, basic biology, behaviour,
ecology and management of exotic D.
suzukii (Diptera: Drosophilidae) with
particular emphasis to the Italian situation.
D. suzukii is native to the South East
Asia and was found for the first time outside
its native habitat in the Hawaiian Islands in
1980, then in California and in Spain in 2008.
Over the last 5 years the species has been
found in many States of North America and
several European countries. In Italy D.
suzukii was identified for the first
time in Trentino-Alto Adige in 2009, with
subsequent detections in Piedmont, Valle
d'Aosta, Lombardy, Veneto, Emilia-Romagna,
Tuscany, Liguria, Marche, Campania and
recently in Sicily. The species has caused
extensive damage in all Regions where it
became established and has demonstrated a very
rapid expansion. In the Trento Province, for
instance, the damage to small berry fruits
production has been estimated in 3.000.000 €
in 2010. D. suzukii is a polyphagous
insect but the most damages are recorded
mainly on fruits of blueberry, strawberry,
raspberry, cherry, and on some varieties of
grapes. In natural ecosystems D. suzukii
reproduces on blackberry, elder, buckthorn,
etc. Unlike other Drosophilids, D. suzukii
shows the peculiar characteristic of females
being able to lay their eggs inside ripening
fruits, starting from veraison and preferring
fruits with a thin epicarp. Females have a
well-developed saw-like ovipositor, which can
penetrate beneath the skin of host fruits. How
males and females find each other is not yet
well understood. Currently, the species has
established in many European countries and
North America. Control strategies adopted so
far include preventive measures, the use of
specific insecticides and trapping of adults.
Several biocontrol agents, such as parasitoids
of larvae and pupae and natural predators are
under investigation. These studies could help
to apply classical biological control
strategies, by introducing D. suzukii
natural enemies, coming from the pest’s native
habitat. At present, management techniques
referring to an ecological control, as the
“push-pull” strategy, are not developed. Early
investigations are currently focused on the
possibility to reduce pest populations through
the exploitation of the pest association with
endosymbionts; moreover, studies aiming to
investigate D. suzukii host fruits
relationships are also in progress, to
identify the most attractive volatile
compounds, to be used in the preparation of
highly selective and attractive baits for D.
suzukii.
Physical, chemical and sensory characterization of the Thai-crispy pork rind ‘Kaeb Moo’ Sriwattana S., Utama-ang N., Thakeow P., Senapa J., Phimolsiripol Y., Surawang S., Pongsirikul I. and Angeli S. Faculty of Agro-Industry, Chiang Mai University, Thailand Crispy pork rind, called ‘Kaeb Moo’ in Thai,
is a typical and very popular food in the
northern region of Thailand. It is made from
deep frying pork skin, previously cut in
slices. There are basically two different
types of Kaeb Moo, the first one consisting
only of the skin layer and the second one
where subcutaneous fat is also present. Kaeb
Moo may undergo rapid change of quality, as
rancidity, after it has been processed.
However, little has been done so far for
quality assessments and certification of the
Thai crispy pork rind. In this research,
investigations on chemical, physical and
sensorial aspects of Kaeb Moo were performed
in order to determine the quality parameters
of this product. Samples were purchased from
well-known local producers of Chiang Mai
province, or prepared in-house. The average
hardness of each sample ranged from 15.0 to
40.0 kgf, while moisture and fat contents were
0.3 - 2.3 and 20.0 - 36.5%, respectively. The
degrees of lipid oxidation were in the range
of 0.10 - 2.57 μg malondialdehyde g-1.
Volatile compounds were investigated by
headspace-solid phase microextraction
technique and GC-MS. The following compounds
were found: propanal, hexanal, heptanal,
2-heptanone, 2-pentyl furan, heptane, octane,
and 4-methyl octane. Descriptive analysis
profiling was used to express the sensorial
attributes and 18 important attributes of Kaeb
Moo were described by 12 trained panelists.
Finally, consumer acceptance test (n = 400)
using 9-point hedonic scale was carried out in
respect to colour, odour, taste, crispness,
and overall-liking.
Eco-physiology of dorsal versus ventral cuticle in flattened sawfly larvae Boevé J.-L. and Angeli S. Department of Entomology, Royal Belgian Institute of Natural Sciences of Bruxelles, Belgium Platycampus larvae are highly cryptic
leaf feeders characterised by a
dorso-ventrally flattened body, the dorsal
integument resembling a shield. Dorsal and
ventral cuticles from Platycampus
luridiventris were compared by
histology and gel electrophoresis. By
Azan-staining, a red and a blue layer were
distinguished in the dorsal cuticle, while the
ventral cuticle showed one, almost uniform
blue layer, as in both cuticles of control
species. The two cuticles from P. luridiventris
had similar amounts and sodium dodecyl
sulphate-polyacrylamide gel electrophoresis
profiles of soluble proteins, but not
insoluble proteins. One insoluble protein
(MW≈41 kDa) was visible as a large band in the
ventral cuticle only. It is likely that this
protein renders the cuticle elastic, and that
the dorsal, red layer is the exocuticle,
mainly composed of insoluble proteins. We
discuss eco-physiological implications of the
exocuticle in insects. Further, data from the
literature indicate that the defence strategy
in P. luridiventris larvae relies on
being visually cryptic towards avian predators
and tactically cryptic towards arthropod
predators and parasitoids. Crypsis in both
senses is favoured by the shield effect,
itself based on an abnormally thick dorsal
exocuticle. Although the larvae are external
feeders, they may be considered as hidden from
an ecological perspective.
Ecology and management of exotic and endemic Anoplophora glabripennis (Coleoptera: Cerambycidae) Hu J., Angeli S., Schuetz S., Luo Y. and Hajek A.E. Faculty of
Science and Technology, Free University of
Bozen-Bolzano, Italy 1 The Asian longhorned beetle is native to
China and Korea, and was found for the first
time outside its native habitat in the U.S.A.
in 1996, with subsequent detections being made
in Canada and several European countries.
The genome of the model beetle and pest Tribolium castaneum ..., Robertson H.M., Angeli S., Forêt S., ...(Tribolium Genome Sequencing Consortium) Human Genome Sequencing Center, Baylor
College of Medicine, USA Tribolium castaneum is a member of the most species-rich eukaryotic order, a powerful model organism for the study of generalized insect development, and an important pest of stored agricultural products. We describe its genome sequence here. This omnivorous beetle has evolved the ability to interact with a diverse chemical environment, as shown by large expansions in odorant and gustatory receptors, as well as P450 and other detoxification enzymes. Development in Tribolium is more representative of other insects than is Drosophila, a fact reflected in gene content and function. For example, Tribolium has retained more ancestral genes involved in cell-cell communication than Drosophila, some being expressed in the growth zone crucial for axial elongation in short-germ development. Systemic RNA interference in T. castaneum functions differently from that in Caenorhabditis elegans, but nevertheless offers similar power for the elucidation of gene function and identification of targets for selective insect control. PMID: 18362917 [PubMed]
Antennal and behavioral responses of Cis boleti to fungal odor of Trametes gibbosa Thakeow P., Angeli S., Weissbecker B. and Schuetz S. Institute of Forest Zoology and Forest
Conservation, University of Goettingen,
Germany Cis boleti (Coleoptera: Ciidae) preferentially colonizes fungi from the genus Trametes that are known as important wood decomposers. The aim of our research was to investigate if C. boleti uses the chemical volatile composition of its fungal host, Trametes gibbosa, as a key attraction factor. Therefore, the T. gibbosa fruiting body volatiles were analysed by using gas chromatography-mass spectrometry, with parallel electroantennographic detection (GC-MS/EAD) using adults of C. boleti. Furthermore, we examined the behavioral responses of C. boleti to the T. gibbosa volatile compounds. The dominant component of the T. gibbosa fruiting body bouquet was 1-octen-3-ol. Other volatiles, like the aldehydes hexanal, nonanal, and (E,E)-2,4-decadienal and the terpene alpha-bisabolol, were present in minor quantities. 1-Octen-3-ol was released with a ratio of the (R)- and (S)-enantiomers of 93:7, respectively. Electroantennography (EAG) employing C. boleti antennae yielded consistently dominant responses to 1-octen-3-ol. GC-EAD and EAG responses to pure standard compounds showed that C. boleti also perceived other host fungal volatiles. A highly significant attraction to 1-octen-3-ol was observed in behavioral tests. Female beetles were significantly attracted to the (S)-(+)- enantiomer at 10 times lower doses than male beetles. Our finding is the first direct proof that ciid beetles use 1-octen-3-ol as a key cue for host finding. PMID: 18283043 [PubMed]
Use of CLSA and SPME-headspace techniques followed by GC-MS analysis to extract and identify the floral odorants Shonouda M., Angeli S., Schuetz S. and Vidal S. AgroEntomology Section, Department of Crop Sciences, University of Goettingen, Germany Flowers of Ziziphus spina christi are known to be attractive for parasitoids and predators. In Y-tube olfactometer experiments, the dried flowers attracted significantly (p < 0.001) the female parasitoids Aphelinus abdominalis. The flower volatile compounds were analyzed to understand which compounds could be specifically responsible for this attractiveness. The volatile compounds of Ziziphus flowers were extracted by closed-loop-stripping-analysis (CLSA) and also by solid phase microextraction (SPME) followed by gas chromatography-mass spectrometry (GC-MS) analysis. The main chemical classes of the volatile compounds are aldehydes, monoterpene-alcohols, ketones and hydrocarbons. Flower extract and some specific compounds will be further tested for their responsiveness to predators and parasitoids in behavioural and electrophysiological experiments. PMID: 18819533 [PubMed]
Solution structure of a chemosensory protein from the desert locust Schistocerca gregaria Tomaselli S., Crescenzi O., Sanfelice D., Ab E., Wechselberger R., Angeli S., Scaloni A., Boelens R., Tancredi T., Pelosi P. and Picone D. Department of Chemistry, University of Naples, Italy Chemical stimuli, generally constituted by small volatile organic molecules, are extremely important for the survival of different insect species. In the course of evolution, insects have developed very sophisticated biochemical systems for the binding and the delivery of specific semiochemicals to their cognate membrane-bound receptors. Chemosensory proteins (CSPs) are a class of small soluble proteins present at high concentration in insect chemosensory organs; they are supposed to be involved in carrying the chemical messages from the environment to the chemosensory receptors. In this paper, we report on the solution structure of CSPsg4, a chemosensory protein from the desert locust Schistocerca gregaria, which is expressed in the antennae and other chemosensory organs. The 3D NMR structure revealed an overall fold consisting of six alpha-helices, spanning residues 13-18, 20-31, 40-54, 62-78, 80-90, and 97-103, connected by loops which in some cases show dihedral angles typical of beta-turns. As in the only other chemosensory protein whose structure has been solved so far, namely, CSP from the moth Mamestra brassicae, four helices are arranged to form a V-shaped motif; another helix runs across the two V's, and the last one is packed against the external face. Analysis of the tertiary structure evidenced multiple hydrophobic cavities which could be involved in ligand binding. In fact, incubation of the protein with a natural ligand, namely, oleamide, produced substantial changes to the NMR spectra, suggesting extensive conformational transitions upon ligand binding. PMID: 16939212 [PubMed]
Surface structure, model and mechanism of an insect integument adapted to be damaged easily Boevé J.-L., Ducarme V., Mer tens T., Bouillard P., Angeli S. Department of Entomology, Royal Belgian Institute of Natural Sciences of Bruxelles, Belgium BACKGROUND: Several sawfly larvae of the
Tenthredinidae (Hymenoptera) are called easy
bleeders because their whole body integument,
except the head capsule, disrupts very easily
at a given spot, under a slight mechanical
stress at this spot. The exuding haemolymph
droplet acts as a feeding deterrent towards
invertebrate predators. The present study
aimed to describe the cuticle surface, to
consider it from a mechanistic point of view,
and to discuss potential consequences of the
integument surface in the predator-prey
relationships. RESULTS: The integument surface
of sawfly larvae was investigated by light
microscopy (LM) and scanning electron
microscopy (SEM) which revealed that the
cuticle of easy bleeders was densely covered
by what we call "spider-like" microstructures.
Such microstructures were not detected in
non-easy bleeders. A model by finite elements
of the cuticle layer was developed to get an
insight into the potential function of the
microstructures during easy bleeding. Cuticle
parameters (i.e., size of the
microstructures and thickness of the epi-
versus procuticle) were measured on integument
sections and used in the model. A shear force
applied on the modelled cuticle surface led to
higher stress values when microstructures were
present, as compared to a plan surface.
Furthermore, by measuring the diameter of a
water droplet deposited on sawfly larvae, the
integument of several sawfly species was
determined as hydrophobic (e.g., more
than Teflon®), which was related to the sawfly
larvae's ability to bleed easily. CONCLUSION:
Easy bleeders show spider-like microstructures
on their cuticle surface. It is suggested that
these microstructures may facilitate
integument disruption as well as render the
integument hydrophobic. This latter property
would allow the exuding haemolymph to be
maintained as a droplet at the integument
surface.
Plant stress proteins of the thaumatin-like family discovered in animals Brandazza A., Angeli S., Tegoni M., Cambillau C. and Pelosi P. Dipartimento di Chimica e Biotecnologie Agrarie, University of Pisa, Italy Thaumatin-like proteins (TLPs) are polypeptides of about 200 residues synthesized by plants in response to fungal infection. In addition to the exceptionally strong sweet taste exhibited by some members, they are also reported to be endowed with endo-beta-1,3-glucanase activity and alpha-amylase inhibiting properties. However, the detailed mechanism of their antifungal action is not completely understood. So far, TLPs have only been described in plants, with several members of the family expressed in the same species. Here, for the first time in animals, we report the identification of two genes encoding members of the thaumatin-like proteins family in the desert locust Schistocerca gregaria and show their expression in different parts of the body. Southern blot and Western blot experiments revealed the presence of orthologous genes and their expression products in the related species Locusta migratoria. A search through the available genomes yielded similar sequences in the nematode Caenorhabditis but not in Drosophila and other insects. A three-dimensional model of S. gregaria TLP suggests a glucanase function. As in plants, TLPs could play a defense role in insects against pathogens.PMID: 15304314 [PubMed]
Chemosensory proteins of Locusta migratoria Ban L., Scaloni A., Brandazza A., Angeli S., Zhang L., Yan Y. and Pelosi P. Dipartimento di Chimica e Biotecnologie Agrarie, University of Pisa, Italy Two different classes of chemosensory proteins (CSPs) in Locusta migratoria have been identified on the basis of the molecular cloning of a series of different cDNAs from the antennae of this insect. Several CSP isoforms have been purified and biochemically characterized from antennal and wing extracts, some of them corresponding to expression products predicted for the identified cDNAs. In wings, the nature of the main endogenous ligand binding to these proteins was determined as oleoamide by a gas chromatography–mass spectrometric approach. One of these isoforms has been expressed in a bacterial system with high yield and used in a fluorescent binding assay. Competitive binding experiments have indicated the presence of long-chain compounds among the best ligands.PMID: 12653934 [PubMed]
Ultrastructural characterization of antennal sensilla and immunocytochemical localization of a chemosensory protein in Carausius morosus Brünner (Phasmida: Phasmatidae) Monteforti G., Angeli S., Petacchi R. and Minnocci A. Sant'Anna School of Advanced Studies of Pisa, Italy The aim of this work was to investigate the olfactory system of the walking stick insect, Carausius morosus. Morphological, ultrastructural and immunocytochemical studies of adult female antennae were conducted by scanning and transmission electron microscopy. Extensive cross-section series were made through the last antennal segment to define the cuticular apparatus, wall pore distribution and the number of innervating receptor neurons of each sensillum type. Single-walled wall pore sensilla occur in three subtypes: (i) with 27 or 28 branched receptor neurons, (ii) with two branched neurons and (iii) with one or two unbranched neurons, respectively. Double-walled wall pore sensilla were found in two subtypes with spoke channels, one with four unbranched neurons, the other with two unbranched neurons. One terminal pore sensillum was found, showing two cavities within the hair and being innervated by six sensory cells. Immunocytochemical experiments were performed to show the localization of a 19kDa soluble protein found in the chemosensory organs of C. morosus. This protein shows an amino acid sequence homologous to the family of chemosensory proteins (CSP). The polyclonal antibody raised against the purified protein (CSP-cmA) showed, for the first time in CSPs, a strong labeling in olfactory sensilla, specifically in the sensillum lymph surrounding the dendritic branches of SW-WP sensilla and in the uninnervated lumen between the two concentric walls of DW-WP type 1 sensilla.PMID: 18088955 [PubMed]
Bacterial expression and conformational analysis of a chemosensory protein from Schistocerca gregaria Picone D., Crescenzi O., Angeli S., Marchese S., Brandazza A., Ferrara L., Pelosi P. and Scaloni A. Dipartimento di Chimica, University of Naples, Italy. Chemosensory proteins (CSPs) are a class of
small, soluble proteins present at high
concentrations in chemosensory organs of
different insect species. Several pieces of
evidence suggest their involvement in carrying
chemical messages from the environment to
chemosensory receptors. However, a structural
description of the mechanism of delivery has
not been reported. In order to provide the
first detailed conformational characterization
of these molecules, we cloned a specific
isoform (CSP-sg4) from Schistocerca
gregaria and expressed it in Escherichia
coli
Soluble proteins from chemosensory organs of Eurycantha calcarata (Insects, Phasmatodea) Marchese S., Angeli S., Andolfo A., Scaloni A., Brandazza A., Mazza M., Picimbon J., Leal W.S. and Pelosi P. Dipartimento di Chimica e Biotecnologie Agrarie, University of Pisa, Italy Three related nucleotide sequences, encoding
mature proteins of 108-113 amino acids, have
been obtained from antennal cDNA of the
Phasmid Eurycantha calcarata. Among
these, one is also expressed in the tarsi as
demonstrated by N-terminal sequence and mass
spectrometric analyses of protein samples
isolated from both organs. PCR experiments
performed with specific primers, showed that
this species is also expressed in the mouth
organs and in the cuticle, while the other two
are antennal specific. All three isoforms are
similar to Drosophila OS-D and other
proteins reported in several insect orders,
but one of them is significantly different
from the other two. The best conserved
elements are the N-terminal region and the
four cysteine residues. Accurate ESMS
measurements indicated that all cysteines are
involved in two disulphide bonds and ruled out
the occurrence of additional
post-translational modifications. Polyclonal
antibodies, raised against the purified
protein, did not react with proteins of the
same class expressed in another Phasmid
species, Carausius morosus, and in the
orthopteran Schistocerca gregaria, nor
did antibodies against these proteins
recognise those of E. calcarata.
Purification and molecular cloning of chemosensory proteins from Bombyx mori Picimbon J.F., Dietrich K., Angeli S., Scaloni A., Krieger J., Breer H. and Pelosi P. Institute for Physiology, University of Hohenheim, Germany. Soluble low molecular weight acidic proteins
are suspected to transport stimulus molecules
to the sensory neurons within insect sensilla.
From the antennae of Bombyx mori, we
have purified and sequenced a protein
(BmorCSP1) bearing sequence similarity to a
class of soluble chemosensory proteins
recently discovered in several orders of
insects. Based on its N-terminal sequence, the
cDNA encoding this protein has been amplified
and cloned. Differential screening of a B.
mori antennal cDNA library led to the
identification of a second gene encoding a
related protein (BmorCSP2), sharing 35-40%
identity to BmorCSP1 and chemosensory proteins
from other species. The predicted secondary
structures of moth's, chemosensory proteins
comprise alpha-helical foldings at conserved
positions and a reduced hydrophobicity with
respect to this novel family of chemosensory
proteins.
Structural analysis and disulfide-bridge pairing of two odorant-binding proteins from Bombyx mori Scaloni A., Monti M., Angeli S. and Pelosi P. Centro Internazionale Servizi di
Spettrometria di Massa-IABBAM, National
Research Council, Italy Pheromone-binding protein (PBP) and general
odorant-binding proteins (GOBPs) were purified
from the antennae of Bombyx mori and
structurally characterised. The amino acid
sequence of GOBP-2 has been corrected. The
disulphide arrangements of PBP and GOBP-2 have
been determined by a combined mass
spectrometric/Edman degradation approach. The
same cysteine pairings, Cys19-Cys54,
Cys50-Cys108, and Cys97-Cys117, were found in
both proteins, suggesting that such patterns
occur commonly throughout this family of
molecules. This arrangement of disulphide
bonds indicates that the three-dimensional
structure of insect OBPs is defined by three
loops, rich in helical content, which can vary
in size and charge distribution from one
protein to another.
Purification, structural characterization, cloning and immunocytochemical localization of chemoreception proteins from Schistocerca gregaria Angeli S., Ceron F., Scaloni A., Monti M., Monteforti G., Minnocci A., Petacchi R. and Pelosi P. Sant'Anna School of Advanced Studies of Pisa, Italy Soluble low-molecular-mass protein isoforms
were purified from chemosensory organs
(antennae, tarsi and labrum) of the desert
locust Schistocerca gregaria. Five
genes encoding proteins of this group were
amplified by PCR from cDNAs of tarsi and
sequenced. Their expression products are
polypeptide chains of 109 amino acids showing
40-50% sequence identity with putative
olfactory proteins from Drosophila
melanogaster and Cactoblastis
cactorum. Direct structural
investigation on isoforms purified from
chemosensory organs revealed the presence in
the expression products of two of the genes
cloned. Two additional protein isoforms were
detected and their molecular structure
exhaustively characterized. MS analysis of all
isoforms demonstrated that the four cysteine
residues conserved in the polypeptide chain
were involved in disulfide bridges
(Cys29-Cys38 and Cys57-Cys60) and indicated
the absence of any additional
post-translational modifications.
Immunocytochemistry experiments, performed
with rabbit antiserum raised against the
protein isoform mixture, showed selective
labelling of the outer lymph in contact
sensilla of tarsi, maxillary palps and
antennae. Other types of sensilla were not
labelled, nor were the cuticle and dendrites
of the sensory cells. No binding of
radioactively labelled glucose or bicarbonate
was detected, in disagreement with the
hypothesis that this class of proteins is
involved in the CO2-sensing cascade. Our
experimental data suggest that the proteins
described here could be involved in contact
chemoreception in Orthoptera. |
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Last update: 16-09-2015
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