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Kenney, G. E.

Publications and source records attributed to Kenney, G. E..

2 recordsLinked to original sources

CRISPR-mediated engineering of bovine satellite cells for Alpha-Gal Syndrome-compatible cultivated meat

Alpha-gal Syndrome (AGS) is a potentially life-threatening allergy caused by an IgE-mediated immune response to galactose--1,3-galactose (alpha-gal), a carbohydrate epitope present in most mammalian meats. Currently, strict avoidance of mammalian meat remains the primary management strategy for affected individuals, and alpha-gal-free beef is not commercially available. Here, we leverage cultivated meat as a biotechnology plat-form to address this unmet clinical need by engineering alpha-gal-free bovine muscle cells. Using CRISPR/Cas9 genome editing, we disrupted GGTA1, the gene encoding 1,3-galactosyltransferase, in immortalized bovine satellite cells (iBSCs). High-efficiency editing produced clonal GGTA1 knockout iBSCs harboring a homozygous frameshift mutation. Flow cytometry and immunofluorescence confirmed loss of the alpha-gal epitope, while bulk RNA-seq indicated minimal disruption of global gene expression and preserved myogenic differentiation capacity. Importantly, lysates from GGTA1 knockout iBSCs elicited substantially reduced basophil activation in assays using plasma from a patient with AGS, indicating reduced basophil activation consistent with reduced allergenic potential. Together, these findings establish a proof of concept for engineering AGS-compatible cultivated meat and demonstrate the potential of cultivated meat technologies to address human health challenges. HIGHLIGHTS{circ} CRISPR/Cas9-mediated disruption of GGTA1 eliminated alpha-gal from bovine satellite cells {circ}GGTA1 knockout cells retained myogenic identity and differentiation capacity {circ}GGTA1 knockout reduced basophil activation in an alpha-gal syndrome immune assay {circ}Genome-edited bovine cells provide a proof of concept for AGS-compatible cultivated meat

bioengineering↗

A new heme enzyme family forms hydrazine groups in diverse biosynthetic pathways

Nitrogen-nitrogen (N-N) bond formation is an inherently challenging chemical process that plays a key role in the global nitrogen cycle. An array of microbial metalloenzyme complexes has evolved to shuttle nitrogen between biologically accessible reduced or oxidized states and its inert form as dinitrogen (N2) gas. More recently, N-N bond formation has been observed in a more specialized context, natural product biosynthesis. Here, we report the discovery of a unique metalloenzyme complex that forms hydrazine functional groups in the biosynthetic pathways of structurally diverse natural products. This heterodimeric system consists of a heme enzyme from a previously unidentified family and a partner ferredoxin. Together, these enzymes effect the unprecedented four-electron reduction of nitrite (NO2-) to form a hydrazine functional group on a substrate amino acid in an oxygen-independent reaction that resembles primary microbial nitrogen metabolism. These enzymes are unexpectedly widespread among bacteria and are present in diverse genomic contexts, including cryptic biosynthetic gene clusters, highlighting the importance of this previously uncharacterized protein family. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=100 SRC="FIGDIR/small/656397v1_ufig1.gif" ALT="Figure 1000"> View larger version (30K): org.highwire.dtl.DTLVardef@232c7forg.highwire.dtl.DTLVardef@13e46f1org.highwire.dtl.DTLVardef@1a3a2e9org.highwire.dtl.DTLVardef@1c7e32_HPS_FORMAT_FIGEXP M_FIG TOC C_FIG

biochemistry↗