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Polymerase chain reaction (PCR) has proven to be the gold-standard for SARS-CoV-2 detection in clinical settings. The most common approaches rely on nasopharyngeal specimens obtained from swabs, followed by RNA extraction, reverse transcription and quantitative PCR. Although swab-based PCR is sensitive, swabbing is invasive and unpleasant to administer, reducing patient compliance for regular testing and resulting in an increased risk of improper sample collection. To overcome these obstacles, we developed a non-invasive one-step RT-qPCR assay performed directly on saliva specimens. The University of Nottingham Asymptomatic Testing Service (UoNATS) protocol simplifies sample collection and bypasses the need for RNA extraction, additives, or extraneous processing steps, thus helping to encourage more regular testing and reducing processing time and costs. We have evaluated the assay against the performance criteria specified by the UK regulatory bodies and attained accreditation (BS EN ISO/IEC 17025:2017) for SARS-CoV-2 diagnostic testing by the United Kingdom Accreditation Service (UKAS). We observed a sensitivity of 1 viral copy per microlitre of saliva and demonstrated a concordance of >99.4% between our results and those of other accredited testing facilities. We concluded that saliva is a stable medium with surprising longevity, and allows for a highly precise, repeatable, and robust testing method.

Detection of SARS-COV-2 in Saliva Samples

The actinomycete Rhodococcus jostii RHA1 contains a multitude of oxygenase enzymes, consonant with its remarkable activities in the catabolism of hydrophobic xenobiotic compounds. In the interests of identifying activities for the transformation of drug molecules, we have cloned genes encoding 23 cytochrome P450 heme domains from R. jostii and expressed them as fusions with the P450 reductase domain (RhfRED) of cytochrome P450Rhf from Rhodococcus sp. NCIMB 9784. Fifteen of the fusions were expressed in the soluble fraction of Escherichia coli Rosetta (DE3) cells. Strains expressing the fusions of RhfRED with genes ro02604, ro04667, ro11069, ro11320, ro11277, ro08984 and ro04671 were challenged with 48 commercially available drugs revealing many different activities commensurate with P450-catalyzed hydroxylation and demethylation reactions. One recombinant strain, expressing the fusion of P450 gene ro11069 (CYP257A1) with RhfRED, and named Ro07-RhfRED, catalyzed the N-demethylation of diltiazem and imipramine. This observation was in accord with previous reports of this enzyme's activity as a demethylase of alkaloid substrates. Ro07-RhfRED was purified and characterised, and applied in cell-free biotransformations of imipramine (7 μM) giving a 63% conversion to the N-desmethyl product.

Two complex structures of the γ-aminobutyrate (GABA) transaminase A1R958 from Arthrobacter aurescens TC1 are presented. The first, determined to a resolution of 2.80 A, features the internal aldimine formed by reaction between the ∊-amino group of Lys295 and the cofactor pyridoxal phosphate (PLP); the second, determined to a resolution of 2.75 A, features the external aldimine adduct formed between PLP and GABA in the first half-reaction. This is the first structure of a microbial GABA transaminase in complex with its natural external aldimine and reveals the molecular determinants of GABA binding in this enzyme.

Cytochromes P450 (P450s) are a family of haem-containing oxidases with considerable potential as tools for industrial biocatalysis. Organismal genomes are revealing thousands of gene sequences that encode P450s of as yet unknown function, the exploitation of which will require high-throughput tools for their isolation and characterisation. In this report, a ligationindependent cloning vector "LICRED" is described that enables the high-throughput generation of libraries of redox-self-sufficient P450s by fusing a range of P450 haem domains to the reductase of P450RhF (RhF-Red) in a robust and generically applicable way. Cloning and expression of fusions of RhF-Red with the haem domains of P450cam and P450-XplA resulted in soluble, active, redox-self-sufficient, chimeric enzymes. In vitro studies also revealed that electron transfer from NADPH to haem was primarily intramolecular. The general applicability of the LICRED platform was then demonstrated through the creation of a library of RhF-Red fusion constructs by using the diverse complement of P450 haem domains identified in the genome of Nocardia farcinica. The resultant fusion-protein library was then screened against a panel of substrates; this revealed chimeric enzymes competent for the hydroxylation of testosterone and methyltestosterone, and the dealkylation of 7-ethoxycoumarin.

‘Impressive’ will not do when describing this volume. No adequate word exists. Its scope is far wider than its short title suggests. Engravers who made their name in other areas of the engraving pr...

SUDDENLY, in these days of war‐waging against planners, developers, and demolition contractors, local history has come into its own. In almost any part of the country you care to name, local amenity societies are popping up to defend, conserve, preserve, and restore the little, if we are lucky, ‘they’ have still left us with. All of which is — or ought to be — very heartening for local history librarians.

‘CARTO‐BIBLIOGRAPHY’ must surely be just about the ugliest term in a cartographer's vocabulary, but to its inventor, Sir Henry George Fordham, it represented something of the very greatest significance, and it is as well for us that it did. It was in 1896 that Sir George made his decision to compile a catalogue of Hertfordshire maps, ‘little conscious’, he was later to confide, ‘of the amplitude such a work could assume’. Can there be anyone who has undertaken a carto‐bibliography since who has not echoed at some point Fordham's confession? Working alone, and without guidance from any similar previous compilations, he had no choice but to devise his own forms, methods, and arrangements, ‘digesting my materials’, as he put it, ‘according to the lights they seemed to throw upon the subject’. The resulting compilation, the first real British carto‐bibliography to see the light of day, began to appear in the Transactions of the Hertfordshire Natural History Society in October 1901. Six years later, in September 1907, it was completed and published in volume form as Hertfordshire maps: a descriptive catalogue of the maps of the county, 1579–1900. A supplement followed in 1914.

Until quite recently librarians on the whole were ill‐equipped for being custodians of maps. Even now one fears this is less rarely the case than it ought to be. Hair‐raising stories of early maps in public libraries, wrongly dated, wrongly ascribed, completely unorganised, accounts of antique atlases deposited with love by nineteenth‐century aldermanic benefactors, unguarded, rebound in buckram bindings with ‘912’ stamped on their spines — these and other horror stories are still being swopped by bemused researchers who have had the fortune to stumble on them. What makes this sort of thing the more disturbing is that the number of maps — thanks to natural wear and tear and exports to American universities — is constantly diminishing. Decreasing numbers and increasing demand spells soaring prices. A copy of Horwood's 32 sheet map of London 1792–99 went for £3 at the Gardner sale in 1924. Today one would have to pay something in the region of £250 for the same map. Just on financial grounds alone then we have something of a moral duty to know about our map stocks.