Functional expression of human cathepsin S in Saccharomyces cerevisiae. Purification and characterization of the recombinant enzyme.

A cDNA encoding the human lysosomal cysteine proteinase cathepsin S precursor has been expressed in yeast using the pVT100-U expression vector containing the alpha-factor promoter. The procathepsin S gene was expressed either as a fusion protein with the pre-region or with the prepro-region of the yeast alpha-factor precursor gene. Following in vitro processing both constructs gave an identical active mature enzyme with a molecular weight of 24,000. After prolonged cultivation of the cells the recombinant protein is also found as an active proteinase in the culture supernatant. The precursor can be activated in vitro at pH 4.5 and 40 degrees C under reducing conditions. The in vitro activated enzyme has a 6-amino acid NH2-terminal extension when compared with the native bovine enzyme. The purified enzyme displays a bell-shaped pH activity profile with a pH optimum of 6.5 and pK values of 4.5 and 7.8. The isoelectric point of the recombinant human cathepsin S is between 8.3 and 8.6 and about 1.5 pH units higher than for the bovine enzyme. The kinetic data for several synthetic substrates and inhibitors reveal a preference for smaller amino acid residues in the binding subsites S2 and S3 of cathepsin S. Like the bovine enzyme, the recombinant human cathepsin S is characterized by a broader range of pH stability (pH 5-7.5) than cathepsins B and L

The energy spectrum of cosmic rays beyond the turn-down around 10^17 eV as measured with the surface detector of the Pierre Auger Observatory

We present a measurement of the cosmic-ray spectrum above 100 PeV using the part of the surface detector of the Pierre Auger Observatory that has a spacing of 750 m. An inflection of the spectrum is observed, confirming the presence of the so-called second-knee feature. The spectrum is then combined with that of the 1500 m array to produce a single measurement of the flux, linking this spectral feature with the three additional breaks at the highest energies. The combined spectrum, with an energy scale set calorimetrically via fluorescence telescopes and using a single detector type, results in the most statistically and systematically precise measurement of spectral breaks yet obtained. These measurements are critical for furthering our understanding of the highest energy cosmic rays

Reconstruction of events recorded with the surface detector of the Pierre Auger Observatory

Cosmic rays arriving at Earth collide with the upper parts of the atmosphere, thereby inducing extensive air showers. When secondary particles from the cascade arrive at the ground, they are measured by surface detector arrays. We describe the methods applied to the measurements of the surface detector of the Pierre Auger Observatory to reconstruct events with zenith angles less than 60o using the timing and signal information recorded using the water-Cherenkov detector stations. In addition, we assess the accuracy of these methods in reconstructing the arrival directions of the primary cosmic ray particles and the sizes of the induced showers

Missense Variants in the Histone Acetyltransferase Complex Component Gene TRRAP Cause Autism and Syndromic Intellectual Disability

Contains fulltext : 202928.pdf (publisher's version ) (Open Access)Acetylation of the lysine residues in histones and other DNA-binding proteins plays a major role in regulation of eukaryotic gene expression. This process is controlled by histone acetyltransferases (HATs/KATs) found in multiprotein complexes that are recruited to chromatin by the scaffolding subunit transformation/transcription domain-associated protein (TRRAP). TRRAP is evolutionarily conserved and is among the top five genes intolerant to missense variation. Through an international collaboration, 17 distinct de novo or apparently de novo variants were identified in TRRAP in 24 individuals. A strong genotype-phenotype correlation was observed with two distinct clinical spectra. The first is a complex, multi-systemic syndrome associated with various malformations of the brain, heart, kidneys, and genitourinary system and characterized by a wide range of intellectual functioning; a number of affected individuals have intellectual disability (ID) and markedly impaired basic life functions. Individuals with this phenotype had missense variants clustering around the c.3127G>A p.(Ala1043Thr) variant identified in five individuals. The second spectrum manifested with autism spectrum disorder (ASD) and/or ID and epilepsy. Facial dysmorphism was seen in both groups and included upslanted palpebral fissures, epicanthus, telecanthus, a wide nasal bridge and ridge, a broad and smooth philtrum, and a thin upper lip. RNA sequencing analysis of skin fibroblasts derived from affected individuals skin fibroblasts showed significant changes in the expression of several genes implicated in neuronal function and ion transport. Thus, we describe here the clinical spectrum associated with TRRAP pathogenic missense variants, and we suggest a genotype-phenotype correlation useful for clinical evaluation of the pathogenicity of the variants

Hydrothermal synthesis of amorphous MoS₂nanofiber bundles via acidification of ammonium heptamolybdate tetrahydrate

<p>Abstract</p><p>MoS₂nanofiber bundles have been prepared by hydrothermal method using ammonium molybdate with sulfur source in acidic medium and maintained at 180 &#176;C for several hours. The obtained black crystalline products are characterized by powder X-ray diffraction (PXRD), Fourier transform infrared spectrometer (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The PXRD pattern of the sample can be readily indexed as hexagonal 2H-MoS₂. FTIR spectrum of the MoS₂shows the band at 480 cm^&#8722;1corresponds to the &#947;_as(Mo-S). SEM/TEM images of the samples exhibit that the MoS₂nanofiber exist in bundles of 120&#8211;300 nm in diameter and 20&#8211;25 &#956;m in length. The effects of temperature, duration and other experimental parameters on the morphology of the products are investigated.</p

The FRAM robotic telescope for atmospheric monitoring at the Pierre Auger Observatory

FRAM (F/Photometric Robotic Atmospheric Monitor) is a robotic telescope operated at the Pierre Auger Observatory in Argentina for the purposes of atmospheric monitoring using stellar photometry. As a passive system which does not produce any light that could interfere with the observations of the fluorescence telescopes of the observatory, it complements the active monitoring systems that use lasers. We discuss the applications of stellar photometry for atmospheric monitoring at optical observatories in general and the particular modes of operation employed by the Auger FRAM. We describe in detail the technical aspects of FRAM, the hardware and software requirements for a successful operation of a robotic telescope for such a purpose and their implementation within the FRAM system