Approaches for High-throughput Quantification of Periplasmic Recombinant Proteins

The Gram-negative periplasm is a convenient location for the accumulation of many recombinant proteins including biopharmaceutical products. It is the site of disulphide bond formation, required by some proteins (such as antibody fragments) for correct folding and function. It also permits simpler protein release and downstream processing than cytoplasmic accumulation. As such, targeting of recombinant proteins to the E. coli periplasm is a key strategy in biologic manufacture. However, expression and translocation of each recombinant protein requires optimisation including selection of the best signal peptide and growth and production conditions. Traditional methods require separation and analysis of protein compositions of periplasmic and cytoplasmic fractions, a time- and labour-intensive method that is difficult to parallelise. Therefore, approaches for high throughput quantification of periplasmic protein accumulation offer advantages in rapid process development

Engineering bacteria to produce pure phage-like particles for gene delivery

Natural and engineered phages have been used in many applications, but their use to deliver user-defined genetic cargoes has been hampered by contamination with replicative phage, restricting use of the technology beyond the laboratory. Here we present a method to produce transducing particles without contamination. In addition, we demonstrate the use of a helper phage-free transducing particle preparation as an antimicrobial agent. This will pave the way for the development of new phage-based technologies with greater scope than lytic phage therapy

New Vectors for Urea-Inducible Recombinant Protein Production

We have developed a novel urea-inducible recombinant protein production system by exploiting the Proteus mirabilis urease ureR-ureD promoter region and the ureR AraC-family transcriptional regulator. Experiments using the expression of β-galactosidase and green fluorescent protein (GFP) showed that promoter activity is tightly regulated and that varying the concentration of urea can give up to 100-fold induction. Production of proteins of biopharmaceutical interest has been demonstrated, including human growth hormone (hGH), a single chain antibody fragment (scFv) against interleukin-1β and a potential Neisserial vaccine candidate (BamAENm). Expression levels can be fine-tuned by temperature and different urea concentrations, and can be induced with readily available garden fertilisers and even urine. As urea is an inexpensive, stable inducer, a urea-induced expression system has the potential to considerably reduce the costs of large-scale recombinant protein production

Programming placental nutrient transport capacity

Many animal studies and human epidemiological findings have shown that impaired growth in utero is associated with physiological abnormalities in later life and have linked this to tissue programming during suboptimal intrauterine conditions at critical periods of development. However, few of these studies have considered the contribution of the placenta to the ensuing adult phenotype. In mammals, the major determinant of intrauterine growth is the placental nutrient supply, which, in turn, depends on the size, morphology, blood supply and transporter abundance of the placenta and on synthesis and metabolism of nutrients and hormones by the uteroplacental tissues. This review examines the regulation of placental nutrient transfer capacity and the potential programming effects of nutrition and glucocorticoid over-exposure on placental phenotype with particular emphasis on the role of the Igf2 gene in these processes

Men and masculinity in men's magazines: A review

© 2018 John Wiley & Sons Ltd. This review article provides a thematic synthesis and overview of 30 years of research into the study of men and masculinity in men's magazines. Over 100 articles, book chapters, and books were reviewed to explore how scholars have approached the study of masculinity in such magazines and identify four major areas of inquiry: the commodification of masculinity; the relationship between sexism and misogyny in men's magazines and men's attitudes towards women; the vulnerability of men to, and the role of magazines in the construction of, men's body image anxieties; and the increasing sexualisation of men's bodies. The strengths and potential limitations of these four thematic approaches are identified, including an insufficiently nuanced account of the ways in which men might actually engage with images and ideas about masculinity in such magazines; an overly singular view of male sexuality that naturalises sexist and predatory behaviour; and an overemphasis on men's bodies as sites of vulnerability, risk, or crisis at the expense of more substantive considerations of the relationship between the representation of body modification practices and technologies, and men's embodied identities. The review concludes with an overview of the present field and some suggestions for future research