labdonic

Background: We report an outbreak of SARS coronavirus-2 (SARS-CoV-2) infection among healthcare workers (HCW) in an NHS elective healthcare facility. Methodology: A narrative chronological account of events after declaring an outbreak of SARS-CoV-2 among HCWs. As part of the investigations, HCWs were offered testing during the outbreak. These were: (1) screening by real-time reverse transcriptase polymerase chain reaction (RT- PCR) to detect a current infection; and (2) serum samples to determine seroprevalence...

Young stars are surrounded by a circumstellar disk of gas and dust, within which planet formation can occur. Gravitational forces in multiple star systems can disrupt the disk. Theoretical models predict that if the disk is misaligned with the orbital plane of the stars, the disk should warp and break into precessing rings, a phenomenon known as disk tearing. We present observations of the triple-star system GW Orionis, finding evidence for disk tearing. Our images show an eccentric ring that is misaligned with the orbital planes and the outer disk...

AMP nucleosidase (EC 3.2.2.4) from Escherichia coli and AMP deaminase (EC 3.5.4.6) from bakers' yeast are proposed to regulate cellular AMP levels under allosteric control of the activator ATP and the inhibitor, PO4. Both enzymes contain catalytic sites which bind AMP and regulatory sites which bind ATP. The deduced amino acid sequences of the proteins revealed only one region of homology in which six of eight amino acids are identical. A similar sequence is found in glyceraldehyde-3-phosphate dehydrogenase, phoE, ras proteins, RNA polymerase, K(+)-ATPase, nucleolin, and other proteins expected to have nucleotide or phosphate binding properties...

A trypsin-resistant core peptide of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) was isolated and analyzed by high-energy Cs+ liquid secondary-ion (LSI) mass spectrometric analysis. This analysis provided successful detection of the high-mass disulfide-linked core peptide as well as information confirming the existence of disulfide pairing. Similarly, LSI mass spectrometric analysis of the peptide fragments isolated chromatographically from a Staphylococcus aureus V8 protease digest of rhGM-CSF provided rapid confirmation of the cDNA-derived sequence and determination of the existing disulfide bonds between cysteine residues 54-96 and 88-121...

The carbohydrate content of all of the species of human leukocyte interferon (IFN-alpha) which have been derived from patients with chronic myelogeneous leukemia (CML) and purified to homogeneity has now been determined. Amino sugar content was measured by high-performance liquid chromatography and fluorescamine detection of acid hydrolysates of each sample. Two species showed significant amounts of glucosamine. Most of the purified species of leukocyte interferon from a myeloblast cell line were also tested, and two species were found to contain sugar residues...

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We have purified recombinant human interleukin 4 (huIL-4), formerly named B-cell stimulatory factor-1, from supernatants of COS-7 monkey kidney and L-929 cells transfected with the cDNA for huIL-4. The purified protein exhibited a specific activity of 2.6 X 10(7) units/mg in a T-cell proliferation assay and consisted of multiple components on sodium dodecyl sulfate-polyacrylamide gel electrophoresis exhibiting Mr values of 15,000, 18,000, and 19,000. All forms of huIL-4 eluted on gel filtration chromatography with an apparent Mr of 22,000...

The nonapeptide Cys-Tyr-Cys-Gln-Asp-Pro-Tyr-Val-Lys was prepared by solid-phase peptide synthesis under oxidizing conditions. Fast atom bombardment mass spectrometric analysis of the untreated molecule produced an ion consistent with a structure involving an intramolecular disulfide bond between Cys(1) and Cys(3). Mass spectra of the peptide after treatment with 2-mercaptoethanol gave signals corresponding to the reduced disulfide form of the peptide and to a mixed disulfide of the peptide with 2-mercaptoethanol...

Recombinant murine interleukin-4 (muIL-4) expressed in COS-7 monkey kidney cells was purified to homogeneity by sequential CM-Sepharose, Sephadex G-100 chromatography and mono-S FPLC to a specific activity of 6.10(7) units per mg of protein based on an in vitro HT-2 cell proliferation assay. Two electrophoretic variants, designated a and b, which migrated on SDS-PAGE as a closely spaced doublet with Mr 19,000, were present in the final product. Gas phase sequencing of the purified protein revealed the presence of an N-terminus corresponding to the mature protein predicted from the cDNA sequence and sequencing of a cyanogen bromide digest confirmed 75 of the 120 predicted amino acids...

The structural characterization of the Escherichia coli-expressed human interferon alpha-2b (rh-IFN alpha-2b) was carried out by employing the fast atom bombardment (FAB) and plasma desorption (PD) mapping methods. The mass spectral data of the rh-IFN alpha-2b and the trypsin-generated peptide mixture allowed rapid and facile confirmation of the cDNA-derived sequence and determination of the existing disulfide pattern in the protein molecule. The same PD/FAB mapping approach was successfully employed in the structural determination of the iodination reaction product of rh-IFN alpha-2b and the potent vasoconstrictor peptide endothelin...

p19 is a highly conserved 19-kDa cytosolic protein that undergoes phosphorylation in mammalian cells upon activation of several distinct signal transduction pathways. Its expression is widespread but developmentally regulated. To determine the in vivo phosphorylation site(s) of p19, the protein was purified from bovine brain and resolved into the unphosphorylated form (p19) and a mixture of the two predominant phospho-forms (pp19). Proteolytic fragments of p19 and pp19 were examined by liquid chromatography/mass spectrometry (LC/MS)...