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Abstract BackgroundAstyanax mexicanusis a well‐established fish model system for evolutionary and developmental biology research. These fish exist as surface forms that inhabit rivers and 30 different populations of cavefish. Despite important progress in the deployment of new technologies, deep mechanistic insights into the genetic basis of evolution, development, and behavior have been limited by a lack of transgenic lines commonly used in genetic model systems. ResultsHere, we expand the toolkit of transgenesis by characterizing two novel stable transgenic lines that were generated using the highly efficientTol2system, commonly used to generate transgenic zebrafish. A stable transgenic line consisting of the zebrafish ubiquitin promoter expresses enhanced green fluorescent protein ubiquitously throughout development in a surface population ofAstyanax. To define specific cell‐types, a Cntnap2‐mCherry construct labels lateral line mechanosensory neurons in zebrafish. Strikingly, both constructs appear to label the predicted cell types, suggesting many genetic tools and defined promoter regions in zebrafish are directly transferrable to cavefish. ConclusionThe lines provide proof‐of‐principle for the application ofTol2transgenic technology inA. mexicanus. Expansion on these initial transgenic lines will provide a platform to address broadly important problems in the quest to bridge the genotype‐phenotype gap.
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Breakdown of polyethylene therepthalate microplastics under saltwater conditions using engineered Vibrio natriegens
Abstract Poly(ethylene terephthalate) (PET) is a highly recyclable plastic that has been extensively used and manufactured. Like other plastics, PET resists natural degradation, thus accumulating in the environment. Several recycling strategies have been applied to PET, but these tend to result in downcycled products that eventually end up in landfills. This accumulation of landfilled PET waste contributes to the formation of microplastics, which pose a serious threat to marine life and ecosystems, and potentially to human health. To address this issue, our project leveraged synthetic biology to develop a whole‐cell biocatalyst capable of depolymerizing PET in seawater environments by using the fast‐growing, nonpathogenic, moderate halophileVibrio natriegens. By leveraging a two‐enzyme system—comprising a chimera ofIsPETase andIsMHETase fromIdeonella sakaiensis—displayed onV. natriegens, we constructed whole‐cell catalysts that depolymerize PET and convert it into its monomers in salt‐containing media and at a temperature of 30°C.
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- Award ID(s):
- 2029327
- PAR ID:
- 10475295
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- AIChE Journal
- Volume:
- 69
- Issue:
- 12
- ISSN:
- 0001-1541
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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