Genomic and Proteomic Characterisation of the European House Dust Mite, Dermatophagoides pteronyssinus

House dust mites are major causative agents in the pathogenesis of allergy. Their proximity with human habitats, association with development of allergenic diseases, and resistance to physical and chemical control measures; make them some of the most medically important mites. Understanding of house dust mites has been hampered by a lack of genomic sequence data and limited to a discrete number of proteins. The work presented here is a detailed characterisation of the European house dust mite, Dermatophagoides pteronyssinus airmid strain, at the genomic and proteomic level. Genomic sequencing and assembly resulted in a high-quality assembly of 70.76 Mb in size with 96.86% coverage. A comprehensive bioinformatic and proteomic examination was conducted on the 12,530 predicted proteins, validating the expression of 4,002. A small group of D. pteronyssinus airmid proteins showed significant homology to known allergens from other species. A large scale comparative proteomic investigation of the mite body and spent growth medium allowed for: (i) qualitative assessment of allergen localisation and (ii) the identification of numerous enzymes that may be involved in key physiological activities. The characterisation of protein extracts from house dust also identified a substantial number of uncharacterised D. pteronyssinus proteins in addition to known and putative allergens. The genes encoding novel β-1,3 glucanases were identified within a trigene cluster in D. pteronyssinus airmid. Recombinant protein expression, biochemical and proteomic analysis revealed Glu1 and Glu2 to exhibit hydrolytic activity toward β-1,3 glucans and have increased expression in the mite body and excretome of D. pteronyssinus in response to yeast diet. Further proteomic and enzymatic analysis correlated glucanase activity in house dust with presence of Glu1 and Glu2. These findings provide evidence that active β-1,3 glucanases are expressed and excreted in the faeces of D. pteronyssinus in response to fungal diet, in both the laboratory and the wild-type environment

An educational blueprint

ArticleMS201

Editorial: Fear of the unknown

EditorialMS201

The Value of Proximity to External Amenities and Mountain Views in the Metropolitan Denver Residential Housing Market

This research examines how natural amenities, such as views of Colorado’s Front Range mountains and proximity to lakes, parks and recreational areas, as well as proximity to community amenities such as hospitals, active wastewater treatment plants, fire and a police stations impact residential housing prices in Adams, Arapahoe and Denver Counties using a hedonic pricing model. Views of the mountains produced the most impact on home sale value in 2000 followed by proximity to a lake of 250 feet. These results demonstrate the importance of environmental amenities to single-family home buyers and can be used to inform parties involved in the future development of the area

Some reflections on the moral quandary of 1960 Africa

MJS201

Pasture Management to Improve Dry Matter Intake

Agricultural producers are constantly looking for ways to maximize returns while reducing input costs. On dairy operations, a move from confinement feeding to pasture grazing offers the potential to reduce costs associated with harvest and storage of feed. In such a transition, producers sometimes report a decline in milk production and growth of livestock—both of which can strongly correlate to dry matter intake. Fortunately, dry matter intake is something that can be influenced by management practices. In this publication, we discuss the pasture management practices to improve dry matter intake

Identification of Radiopure Titanium for the LZ Dark Matter Experiment and Future Rare Event Searches

The LUX-ZEPLIN (LZ) experiment will search for dark matter particle interactions with a detector containing a total of 10 tonnes of liquid xenon within a double-vessel cryostat. The large mass and proximity of the cryostat to the active detector volume demand the use of material with extremely low intrinsic radioactivity. We report on the radioassay campaign conducted to identify suitable metals, the determination of factors limiting radiopure production, and the selection of titanium for construction of the LZ cryostat and other detector components. This titanium has been measured with activities of $^{238}$U$_{e}$~$<$1.6~mBq/kg, $^{238}$U$_{l}$~$<$0.09~mBq/kg, $^{232}$Th$_{e}$~$=0.28\pm 0.03$~mBq/kg, $^{232}$Th$_{l}$~$=0.25\pm 0.02$~mBq/kg, $^{40}$K~$<$0.54~mBq/kg, and $^{60}$Co~$<$0.02~mBq/kg (68\% CL). Such low intrinsic activities, which are some of the lowest ever reported for titanium, enable its use for future dark matter and other rare event searches. Monte Carlo simulations have been performed to assess the expected background contribution from the LZ cryostat with this radioactivity. In 1,000 days of WIMP search exposure of a 5.6-tonne fiducial mass, the cryostat will contribute only a mean background of $0.160\pm0.001$(stat)$\pm0.030$(sys) counts.Comment: 13 pages, 3 figures, accepted for publication in Astroparticle Physic