Biology subjects

Hurst, G.

Publications and source records attributed to Hurst, G..

4 recordsLinked to original sources

bioRxiv2026

Investigations into cyanobacteria, plant, and insect protein extracts as serum-replacement supplements for the expansion of cells for cultivated meat

Cultivated meat has undeniable potential to address some of the current detrimental impacts of animal farming, while addressing food security worldwide. However, one of the main challenges in cultivated meat production is manufacturing cost. The main contributor to cost is the culture media which comprises expensive components such as growth factors and animal-derived proteins. This study investigated alternative, food grade, high protein extracts as serum replacements in serum-free media formulations. The extracts were chosen to represent various sustainable sources of proteins: marine (spirulina e.g. cyanobacterium), plant (faba bean) and insect (mealworm flour). Different processing methods and different solvents were investigated for production of cell culture-compatible extracts which were then tested with mouse myoblasts (C2C12) and primary porcine myosatellites (pMyoSCs). A serum-free medium formulation containing 2.6% v/v spirulina extract was found to support long term growth of C2C12 cells for [~]10 population doublings compared to only [~]2 in the control. The processing steps were optimized, showing that a glycerine solution was best for free amino acid and protein yield (4950 {micro}M total free amino acids, 11.45 mg/mL protein concentration). This solution had a positive effect on C2C12 cells, increasing their growth by up to 20% when added to the B8 medium. However, this benefit did not translate to pMyoSCs, which showed no significant growth increases in short-term screening. This work demonstrates a method for converting food grade protein powders into effective culture media supplements and highlights the potential of spirulina-based extracts for the use in cultivated meat. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=104 SRC="FIGDIR/small/702276v1_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@206658org.highwire.dtl.DTLVardef@11f28ceorg.highwire.dtl.DTLVardef@b00fd6org.highwire.dtl.DTLVardef@dfaaf4_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphical abstractC_FLOATNO Created in BioRender. Gordon-Petrovskii, W. (2025) https://BioRender.com/by7khs1 C_FIG

bioengineering↗

bioRxiv2023

A selfish genetic element and its suppressor causes gross damage to testes in a fly

Selfish genetic elements (SGEs), specifically X-chromosome meiotic drive (XCMD), create huge conflicts within a hosts genome and can have profound effects on fertility. Suppressors are a common evolutionary response to XCMD to negate its costs. However, whether suppressors themselves can cause negative non-target effects remains understudied. Here, we examine whether the intragenomic conflicts created by XCMD and its suppressor affect gonad morphology in Drosophila subobscura. We found significant differences in testes, seminal vesicle, and accessory gland size depending on whether a male carried a non-driving X chromosome, an XCMD, and if the XCMD was suppressed. We also found the first evidence of abnormal testes development that is specifically associated with a suppressor of XCMD. Unlike other studies, our evidence suggests that XCMD in D. subobscura creates major abnormalities to male gonads. These abnormalities are most frequent if both XCMD and its suppressor are both present. While costs of suppression have importance in theoretical models, they have largely been ignored in empirical XCMD systems. Overall, this study highlights that genetic conflict, created by SGEs and their suppressors, is a potent evolutionary force that can have major impacts on gonad development and gametogenesis.

evolutionary biology↗

bioRxiv2022

History matters: thermal environment before, but not during wasp attack determines the efficiency of symbiont-mediated protection

The outcome of natural enemy attack in insects is commonly impacted by the presence of defensive microbial symbionts residing within the host. Beyond their presence, the outcome of the interaction can also depend on genetic and environmental factors. The thermal environment is a key factor known to affect symbiont-mediated traits in insects, including their ability to defend against natural enemy attack. Cooler temperatures, for instance, have been previously shown to reduce Spiroplasma-mediated protection in Drosophila. Here, we dissect the effect of the thermal environment on Spiroplasma-mediated protection against Leptopilina boulardi in Drosophila melanogaster by examining the effect of temperature before, during and after wasp attack on fly survival and wasp success. We observed that the developmental temperature of the mothers of attacked larvae, and not the temperature of the attacked larvae themselves during or after wasp attack, strongly determines the protective influence of Spiroplasma. Spiroplasma-mediated fly survival was found to be weaker when parental flies were reared at 21{degrees}C before their larvae were exposed to wasps compared to larvae derived from parental flies reared at 23{degrees}C or 25{degrees}C. Contrastingly, there was no effect of thermal environment on protection when mothers were reared at 25{degrees}C, and their progeny exposed to lower temperatures during and after wasp attack. The effect of developmental temperature on Spiroplasma-mediated protection is likely mediated by reduced Spiroplasma titre combined, at cooler temperatures, with segregation of infection. These results indicate the historical thermal environment is a stronger determinant of protection than current environment, and that protective capacity is partly an epigenetic trait.

evolutionary biology↗

bioRxiv2020

Invasive freshwater snails form novel microbial symbioses

Resident microbes (microbiota) can shape host organismal function and adaptation in the face of environmental change. Invasion of new habitats exposes hosts to novel selection pressures, but little is known about the impact of invasion on microbiota and the host-microbiome relationship after this transition (e.g., how rapidly symbioses are formed, whether microbes influence invasion success). We used high-throughput 16S rRNA sequencing of New Zealand (native) and European (invasive) populations of the freshwater snail Potamopyrgus antipodarum and found that while invaders do carry over some core microbial taxa from New Zealand, most of their microbial community is distinct. This finding highlights that invasions can result in the formation of novel symbioses. We further show that the native microbiome is composed of fewer core microbes than the microbiome of invasive snails, suggesting that the microbiota is streamlined to essential members. Together, our findings demonstrate that microbiota comparisons across native and invasive populations can reveal the impact of a long coevolutionary history and specialization of microbes in the native host range, as well as new associations occurring after invasion. We lay essential groundwork for understanding how microbial relationships affect invasion success and how microbes may be utilized in the control of invasive hosts.

evolutionary biology↗