Person:
Mandell, Daniel

Profile Picture

Email Address

AA Acceptance Date

Birth Date

Research Projects

Organizational Units

Job Title

Last Name

Mandell

First Name

Daniel

Name

Mandell, Daniel

Filters

20152

Settings

Author's Publications: search.filters.isAuthorOfPublication.728f26d9-4b66-4994-bc16-f5162ce32f52

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Publication
    A general strategy to construct small molecule biosensors in eukaryotes
    (eLife Sciences Publications, Ltd, 2015) Feng, Justin; Jester, Benjamin W; Tinberg, Christine E; Mandell, Daniel; Antunes, Mauricio S; Chari, Raj; Morey, Kevin J; Rios, Xavier; Medford, June I; Church, George; Fields, Stanley; Baker, David
    Biosensors for small molecules can be used in applications that range from metabolic engineering to orthogonal control of transcription. Here, we produce biosensors based on a ligand-binding domain (LBD) by using a method that, in principle, can be applied to any target molecule. The LBD is fused to either a fluorescent protein or a transcriptional activator and is destabilized by mutation such that the fusion accumulates only in cells containing the target ligand. We illustrate the power of this method by developing biosensors for digoxin and progesterone. Addition of ligand to yeast, mammalian, or plant cells expressing a biosensor activates transcription with a dynamic range of up to ~100-fold. We use the biosensors to improve the biotransformation of pregnenolone to progesterone in yeast and to regulate CRISPR activity in mammalian cells. This work provides a general methodology to develop biosensors for a broad range of molecules in eukaryotes. DOI: http://dx.doi.org/10.7554/eLife.10606.001
  • No Thumbnail Available
    Publication
    Biocontainment of Genetically Modified Organisms by Synthetic Protein Design
    (Nature Research, 2015-02-05) Mandell, Daniel; Lajoie, Marc J.; Mee, Michael T.; Takeuchi, Ryo; Kuznetsov, Gleb; Norville, Julie; Gregg, Christopher J.; Stoddard, Barry L.; Church, George
    Genetically modified organisms (GMOs) are increasingly deployed at large scales and in open environments. Genetic biocontainment strategies are needed to prevent unintended proliferation of GMOs in natural ecosystems. Existing biocontainment methods are insufficient either because they impose evolutionary pressure on the organism to eject the safeguard, because they can be circumvented by environmentally available compounds, or because they can be overcome by horizontal gene transfer (HGT). Here we computationally redesign essential enzymes in the first organism possessing an altered genetic code to confer metabolic dependence on nonstandard amino acids for survival. The resulting GMOs cannot metabolically circumvent their biocontainment mechanisms using environmentally available compounds, and they exhibit unprecedented resistance to evolutionary escape via mutagenesis and HGT. This work provides a foundation for safer GMOs that are isolated from natural ecosystems by reliance on synthetic metabolites.