Publications by authors named "Callum McGregor"

Article Synopsis
  • The stability of plasmids in microbial cells is crucial for efficient industrial biocatalysis, as these multicopy systems offer better product outcomes compared to genomic integrations.
  • The study focuses on H16, a bacterium capable of converting inorganic carbon from CO fixation into valuable products, which has struggled with plasmid stability.
  • Researchers developed a plasmid addiction system that stabilized a multicopy plasmid, allowing H16 to successfully produce approximately 10 g/L of mevalonate with carbon yields around 25%, marking a record for C6 compounds from C1 feedstocks.
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3-Hydroxypropionate (3-HP) is a versatile compound for chemical synthesis and a potential building block for biodegradable polymers. Cupriavidus necator H16, a facultative chemolithoautotroph, is an attractive production chassis and has been extensively studied as a model organism for biopolymer production. Here, we engineered C.

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Polyhydroxyalkanoates are attractive alternatives to traditional plastics. However, although polyhydroxybutyrate (PHB) is produced in large quantities by H16, its properties are far from ideal for the manufacture of plastic products. These properties may be improved through its coproduction with 3-hydroxypropionate (3HP), which leads to the formation of the copolymer poly(3-hydroxybutyrate--3-hydroxypropionate) (poly(3HB--3HP).

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Using hydrogen oxidising bacteria to produce protein and other food and feed ingredients is a form of industrial biotechnology that is gaining traction. The technology fixes carbon dioxide into products without the light requirements of agriculture and biotech that rely on primary producers such as plants and algae while promising higher growth rates, drastically less land, fresh water, and mineral requirements. The significant body of scientific knowledge on hydrogen oxidising bacteria continues to grow and genetic engineering tools are well developed for specific species.

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Background: Sepsis and meningitis in neonates and infants are a source of substantial morbidity, mortality and economic loss. The objective of this review is to estimate the acute costs associated with treating sepsis, meningitis and meningococcal septicemia, in neonates and infants, worldwide.

Methods: The electronic databases Medline, Embase and EconLit were searched and exported on November 24, 2018.

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This observational study aimed to describe immunopathogenesis and treatment outcomes in children with and without severe acute malnutrition (SAM) and HIV-infection. We studied markers of microbial translocation (16sDNA), intestinal damage (iFABP), monocyte activation (sCD14), T-cell activation (CD38, HLA-DR) and immune exhaustion (PD1) in 32 HIV-infected children with and 41 HIV-infected children without SAM prior to initiation of antiretroviral therapy (ART) and cross-sectionally compared these children to 15 HIV-uninfected children with and 19 HIV-uninfected children without SAM. We then prospectively measured these markers and correlated them to treatment outcomes in the HIV-infected children at 48 weeks following initiation of ART.

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Disease-free infection in HIV-infected adults is associated with human leukocyte antigen-mediated suppression of viremia, whereas in the sooty mangabey and other healthy natural hosts of simian immunodeficiency virus (SIV), viral replication continues unabated. To better understand factors preventing HIV disease, we investigated pediatric infection, where AIDS typically develops more rapidly than in adults. Among 170 nonprogressing antiretroviral therapy-naïve children aged >5 years maintaining normal-for-age CD4 T cell counts, immune activation levels were low despite high viremia (median, 26,000 copies/ml).

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