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There are concerns that sotrovimab has reduced efficacy at reducing hospitalisation risk against the BA.2 sub-lineage of the Omicron SARS-CoV-2 variant. We performed a retrospective cohort (n = 8850) study of individuals treated with sotrovimab in the community, with the objective of assessing whether there were any differences in risk of hospitalisation of BA.2 cases compared with BA.1. We estimated that the hazard ratio of hospital admission with a length of stay of 2 days or more was 1.17 for BA.2 compared with BA.1 (95%CI 0.74-1.86). These results suggest that the risk of hospital admission was similar between the two sub-lineages., (© 2023 Crown copyright. Influenza and Other Respiratory Viruses published by John Wiley & Sons Ltd. This article is published with the permission of the Controller of HMSO and the King’s Printer for Scotland.)

When SARS-CoV-2 Omicron emerged in 2021, S gene target failure enabled differentiation between Omicron and the dominant Delta variant. In England, where S gene target surveillance (SGTS) was already established, this led to rapid identification (within ca 3 days of sample collection) of possible Omicron cases, alongside real-time surveillance and modelling of Omicron growth. SGTS was key to public health action (including case identification and incident management), and we share applied insights on how and when to use SGTS.

Chatoyant is a tool for the simulation and the analysis of heterogeneous free-space optoelectronic architectures. It is capable of modeling digital and analog electronic and optical signal propagation with mechanical tolerancing at the system level. We present models for a variety of optoelectronic devices and results that demonstrate the system's ability to predict the effects of various component parameters, such as detector geometry, and system parameters, such as alignment tolerances, on system-performance measures, such as the bit-error rate.

The preparation and purification of cyanogen bromide fragments from [(14)C]carboxymethylated coelacanth triose phosphate isomerase is presented. The automated sequencing of these fragments, the lysine-blocked tryptic peptides derived from them, and also of the intact protein, is described. Combination with results from manual sequence analysis has given the 247-residue amino acid sequence of coelacanth triose phosphate isomerase in 4 months, by using 100mg of enzyme. (Two small adjacent peptides were placed by homology with the rabbit enzyme.) Comparison of this sequence with that of the rabbit muscle enzyme shows that 207 (84%) of the residues are identical. This slow rate of evolutionary change (corresponding to two amino acid substitutions per 100 residues per 100 million years) is similar to that found for glyceraldehyde 3-phosphate dehydrogenase. The reliability of sequence information obtained by automated methods is discussed.

Membrane-bound HLA-A and HLA-B antigens have been extensively purified in good yield. The sequences of the N-terminal 16 amino acids have been determined using about 1 nmol of protein eluted from polyacrylamide gel after electrophoresis in sodium dodecyl sulphate.

A partial characterization of the primary structure of D-amino-acid oxidase (D-Amino-acid:oxygen oxidoreductase (deaminating), EC 1.4.3.3.) from hog kidney has been achieved by a CNBr cleavage of the 14C-carboxymethylated protein. Four fragments have been isolated and purified and their alignment made possible by overlapping with methionine-containing peptides derived from tryptic digestion of the 14C-carboxymethylated protein. A partial sequencing of the CNBr fragments has been carried out by the automated Edman procedure and by manual sequence analysis. Chymotryptic peptides containing the 5 alkylated thiols of the monomer enzyme (Curti, B., Ronchi, S., branzoli, U., Ferri, G. and Williams, Jr., C. H. (1973) Biochim. Biophys. Acta 327, 266-273) have been isolated and their sequence determined. The present results do not show any significant homologies with the known sequences of other flavoproteins.

The apparent molecular weight of the purple membrane protein of Halobacterium halobium was found to be 20 000 by sodium dodecyl sulfate gel electrophoresis and by gel filtration in sodium dodecyl sulfate. However, the molecular weight value determined by gel filtration in 6 M guanidine was 28 000. To resolve this discrepancy, methods insensitive to or independent of the conformation of the protein were used to estimate the molecular weight. Analytical ultracentrifugation of the sodium dodecyl sulfate-protein complex, peptide mapping, and amino acid analysis all gave values of 25 000 +/- 1000, a figure in agreement with a recent x-ray study. Borohydride reduction was used to attach the retinal cofactor covalently to a lysine residue. After digestion with thermolysin, peptide maps were prepared of the protein labeled at lysine residues with [14C] succinic anhydride both before and after reduction. Comparison of the maps showed one radioactive peptide with changed mobility. This peptide was isolated and shown to have the sequence Val-Ser-Asp-Pro-Asp-Lys-Lys with only one of the two lysine residues alkylated. Solid-phase sequencing showed the succinyl group to be at position 6 and hence the retinal group to be at position 7. It was possible that a small amount of retinal was also bound to Lys-6. There was no apparent homology with the corresponding peptide of vertebrate rhodopsin. No evidence of chain heterogeneity was found by radiochemical peptide mapping and sequence analysis of peptides containing lysine residues indicating that all protein chains of purple membrane are very similar or identical.

An automatic solid-phase procedure is described for determining the amino-terminal amino acid sequence of very small quantities of proteins. The sample is covalently attached to an inert support so that mechanical and physical losses during sequencing are eliminated. High sensitivity is achieved by using an initial coupling with high specific activity phenyl [35S]isothiocyanate followed by a longer reaction with the unlabeled reagent. The radioactive phenylthiohydantoins are identified by autoradiography after two-dimensional thin-layer chromatography. Unlabeled phenylthiohydantoin-amino acids are added to each fraction to assist in the identification and to act as carriers, hence reducing absorptive and extractive losses of the small quantities of sample. The method may be used on proteins eluted from polyacrylamide gels containing sodium dodecyl sulfate without removal of the detergent. Sequences of up to 20 residues have been obtained on quantities of protein ranging from 2.5 to 70 pmol. Results from proteins of hitherto unknown sequence are included.

1. The complete amino acid sequence of D-glyceraldehyde-3-phosphate dehydrogenase from the moderate thermophile Bacillus stearothermophilus has been determined. 2. This has been achieved largely by the automated sequence analysis of large fragements derived by chemical cleavage with cyanogen bromide, BNPS-skatole [the product of reaction between N-bromosuccinimide and 2-(nitrophenyl-sulphenyl)-3-methylindole] and hydroxylamine and enzymic hydrolysis with trypsin at arginine residues. 3. The sequence is as follows: (See Text). It has been numbered to maximise homology with the four complete sequences of this enzyme from other sources. Hence the N-terminal residue is numberd 0 and two deletions and two insertions have been introduced. 4. The inability of the B. stearothermophilus apo-enzyme to transfer an acyl moiety from Cys-149 to Lys-183 oberved with muscle enzymes is explained by the replacement of lysine by arginine in the enzyme from the thermophilic organism. 5. The sequences of the S-loop regions, which form the core of the tetrameric enzyme, are similar to each other in B. stearothermophilus and Thermus aquaticus and differ from the highly conserved S-loops of three enzymes from mesophiles.

The three major proteins of chick scale keratin were isolated as their S-carboxymethylated derivatives and shown to be similar or identical in molecular weight by gel filtration but to be distinct by amino acid analysis and gel electrophoresis. The major amino-terminal sequence of scale keratin chains was determined and shown to be highly homologous to the corresponding region of feather keratin chains. The carboxyl-terminal peptides of the three scale keratin fractions differed in sequence but were all homologous to the carboxyl-terminal segment of feather keratin chains. The pronounced concentration of cysteine residues at the amino-terminal and carboxyl-terminal segments suggested a similar role for these regions in both scale and feather keratin chains, namely to provide a disulphide-linked matrix to maintain the organisation of fibrils which arise from the internal hydrophobic segments of both types of chain. Analysis of a large hydrophobic segment from each of the three isolated protein fractions revealed that each was composed largely of repeating tripeptide units of the type Gly-Gly-X (where X = Phe, Leu or Tyr). At a few positions in each hydrophobic peptide, microheterogeneity was apparent in the sequences indicating that each isolated protein fraction was composed of at least three different chains each encoded by a different gene. A minimum of nine keratin genes are therefore expressed in scale tissue.

Four unique carboxymethylcysteine-containing peptides were isolated from tryptic and chymotryptic digests of trout muscle actin carboxymethylated with iodo[2-(14)C]acetic acid in 6m-guanidinium chloride. The amino acid sequences of these peptides were determined and showed a high degree of homology with the corresponding sequences from rabbit actin. One of the radioactive peptides was the C-terminal peptide and another sequence probably contained the cysteine residue from the N-terminal region of the protein.