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Worboys, S.

Publications and source records attributed to Worboys, S..

2 recordsLinked to original sources

From mountaintops to metacollections: using genomics to evaluate ex situ conservation collections. A case study from tropical montane cloud forest plants

A core aim of ex situ conservation is to represent wild genetic diversity in managed living collections. For the climate-threatened tropical montane cloud forest (TMCF) flora of northeast Australia, an ex situ metacollection of plants and seeds has been established by the Tropical Mountain Plant Science (TroMPS) project. In this study we used reduced-representation sequencing (DArTseq) of wild, herbarium, and ex situ material alongside provenance information for ten species, to pursue two central aims: to characterise landscape-scale genetic structure across species ranges, and to evaluate how well the assembled metacollections represent that wild diversity. Analyses revealed consistent patterns of genetic differentiation among mountain top populations across multiple species, reflecting the isolating influence of lowland gaps between upland habitats, with the degree of differentiation varying among species. These results provide the first genetic baseline for Australian TMCF flora and reinforce the importance of treating individual mountain top populations as distinct units for conservation management. Additionally, the project provided valuable insights into the logistical challenges of coordinated multi-institutional collecting, informing strategies for metacollection design more broadly. Evaluation of the metacollection revealed both strengths and gaps in representation across species, providing an evidence base to refine the current holdings and guide future targeted collecting to strengthen their long-term conservation value.

genomics↗

Inhibition of systemic mammalian metabolism by carnitine mimics from the gut microbiota

BackgroundThe gut microbiota and microbiome-derived metabolites are implicated in various aspects of human health. Here we sought to determine the systemic effects, and mechanism of action, of microbiome-derived carnitine analogues in germ free and conventionally colonised mice. ResultsHere we report the systemic localization of the microbiome-derived carnitine analogues, 3-methyl-4-(trimethylammonio)butanoate (3M-4-TMAB) and 5-aminovalerate betaine (5-AVAB), post-administration to germ free mice, with systemic carnitine depletion and mitochondrial dysregulation, reflected in altered acylcarnitine profiles due to incomplete carnitine-mediated fatty acid oxidation. Studies on the inhibitory potency of 3M-4-TMAB at the enzymatic, cellular, and organism levels indicate that, in part, this is a result of inhibition of gammabutyrobetaine hydroxylase, which catalyses the final step in carnitine biosynthesis. Systemic administration of 13C- labelled 3M-4-TMAB to conventionally colonised animals to further investigate the physiological relevance of this inhibition, identified a significant reduction in systemic carnitine levels due to increased excretion in urine and faeces and disruption of carnitine-mediated metabolism across ten organs. ConclusionsThese results highlight the physiological relevance and significance of microbiome-derived metabolites in vivo. The depletion of carnitine and inhibition of its function have potentially long-term impacts on both mammalian energy generation and the protective, signalling and immune regulatory effects of this critical molecule.

microbiology↗