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Rutter, J. W.

Publications and source records attributed to Rutter, J. W..

4 recordsLinked to original sources

Engaging cancer patients on their attitudes towards microbiome engineering technologies

Microbiome engineering aims to develop engineered live biotherapeutic products to diagnose and treat human disease. One of the most active areas is in the engineering of modified bacteria that act as cancer therapeutics, with many products currently in clinical trials. With the emergence of any novel technologies, it is important to consult the public and end users throughout their development to address any concerns that may arise from their use. This is particularly true for therapeutics, for which it is vital that both clinicians and patients have confidence in the treatments that are available to them. Here, we surveyed a cohort of cancer patients and their relatives to gauge their knowledge of modern microbiome engineering techniques. We focus predominately on the use of bacterial eLBPs to treat cancer. Overall, most participants indicated that they would be comfortable taking cancer treatment options based on microbiome engineering technologies.

scientific communication and education↗

Bacterial microcompartment utilisation in the human commensal Escherichia coli Nissle 1917

Bacterial microcompartments (BMCs) are self-assembled protein structures often utilised by bacteria as a modular metabolic unit, enabling the catalysis and utilisation of less common carbon and nitrogen sources within a self-contained compartment. The ethanolamine (EA) utilisation (eut) BMC has been widely demonstrated in enteropathogens, such as Salmonella enterica, and current research is exploring its activity in the commensal species that populate the human gut. Escherichia coli Nissle 1917 (EcN) is a strong coloniser and probiotic in gut microbial communities, and has been used extensively for microbiome engineering. In this study, the utilisation of ethanolamine as a sole carbon source and the formation of the eut BMC in EcN were demonstrated through growth assays and visualisation with transmission electron microscopy. Subsequently, flux balance analysis was used to further investigate the metabolic activity of this pathway. It was found that not only is the utilisation of the eut BMC for the degradation of EA as a carbon source in EcN comparable to that of Salmonella enterica, but also that ammonium is released into solution as a byproduct in EcN but not in S. enterica. Control of EA-dependent growth was demonstrated using different concentrations of the operon inducer, vitamin-B12. We show that vitamin B12-dependent EA utilisation as the sole carbon source enables growth in EcN, and demonstrate the concurrent formation of the BMC shell and inducible control of the eut operon.

microbiology↗

An antimicrobial peptide expression platform for targeting pathogenic bacterial species

Bacteriocins are antimicrobial peptides that are naturally produced by many bacteria. They hold great potential in the fight against antibiotic resistant bacteria, including ESKAPE pathogens. However, they often have low stability in vivo and therefore, may not be effective when administered orally. Engineered live biotherapeutic products (eLBPs) that secrete bacteriocins can be created to deliver bacteriocins directly at the site of infection. Here we develop a modular bacteriocin secretion platform that can be used to express and secrete multiple bacteriocins from non-pathogenic Escherichia coli host strains. As a proof of concept we create Enterocin A and Enterocin B secreting strains that show strong antimicrobial activity against Enterococcus faecalis and Enterococcus faecium, and characterise this activity in both solid culture and liquid co-culture. We then develop a Lokta-Volterra model that can be used to capture the interactions of these competitor strains. We show that simultaneous exposure to EntA and EntB can delay the point of Enterococcus growth. Our system has the potential to be used as an eLBP to secrete additional bacteriocins for the targeted killing of other pathogenic bacteria.

synthetic biology↗

Detecting changes in the Caenorhabditis elegans intestinal environment using an engineered bacterial biosensor

Caenorhabditis elegans has become a key model organism within biology. In particular, the transparent gut, rapid growing time and ability to create a defined gut microbiota make it an ideal candidate organism for understanding and engineering the host microbiota. Here we present the development of an experimental model which can be used to characterise whole-cell bacterial biosensors in vivo. A dual-plasmid sensor system responding to isopropyl {beta}-D-1-thiogalactopyranoside was developed and fully characterised in vitro. Subsequently, we show the sensor was capable of detecting and reporting on changes in the intestinal environment of C. elegans after introducing exogenous inducer into the environment. The protocols presented here may be used for aiding the rational design of engineered bacterial circuits, primarily for diagnostic applications. In addition, the model system may serve to reduce the use of current animal models and aid in the exploration of complex questions within general nematode and host-microbe biology.

synthetic biology↗