Biology subjects

Dolgin, J.

Publications and source records attributed to Dolgin, J..

4 recordsLinked to original sources

bioRxiv2026

Precision Fermentation of Recombinant Myofibrillar Proteins for Future Foods

Myofibrillar proteins, namely actin and myosin, are responsible for many of the textural attributes of animal-based meat. Precision fermentation (recombinant production of food ingredients) represents an underexplored approach to producing these proteins without the unsustainable practice of animal agriculture. We show that through the solubility-enhancing SUMO peptide tag and precipitation-based purification, we can produce actin via recombinant DNA methods at titers of 326 mg/L E. coli culture. We also show expression and precipitation of a recombinant fragment of the myosin tail, leading to 572 mg/L culture. For both proteins, yields are improved compared to prior studies, without the need for low-yielding laborious purification columns, with final purities of 69-73%. These recombinant actin and myosin proteins showed macro- and microscopic fibrous features similar to meat. When combined with plant-based proteins, chewiness, hardness, and Youngs modulus were improved towards that of animal-based meat. Preliminary cost analyses suggest a less expensive process for producing myofibrillar proteins compared to established methods. Our results reveal a novel scalable approach to making meat-like foods and ingredients through precision fermentation.

bioengineering↗

bioRxiv2026

Engineered Vibrio natriegens lysate can replace multiple components of cell culture media

Reducing the cost and environmental impact of cell culture media is an important goal for cultivated meat, the process of generating meat in vitro using proliferating animal cells. While prior approaches have demonstrated the use of microbial lysates to replace expensive animal-based fetal bovine serum (FBS) in media, these formulations still rely on large quantities of growth factors such as fibroblast-like growth factor 2 (FGF2). Here, we demonstrate the use of FGF2-expressing Vibrio natriegens to create whole-cell lysates that replace both FBS and FGF2 in cell culture media for cultivated meat applications. This medium, named "VN40FGF", supports rapid proliferation of immortalized bovine muscle satellite cells (iBSCs) in the absence of supplemented FGF2. Cells grown in VN40FGF maintain phenotype and differentiation capacity. We also demonstrate that engineered V. natriegens can grow in spent cell culture media, further improving sustainability and economics, and reducing potential eutrophication concerns associated with waste disposal. Our approach combines multiple strategies for reducing the total number of media inputs, demonstrating opportunities for more economical and sustainable cell culture, especially for cultivated meats.

bioengineering↗

bioRxiv2026

Computational design of blue melanin with peptide motif scaffolding

De novo melanin design seeks to extend natural melanin colors to new, stable colors (blue, purple, green) with sequence-to-color tunability. Natural melanin, polymerized from tyrosine (Y), is a robust pigment with heterogenous molecular weights. Control of melanin size (length) is challenging; thus, only specific colors (yellow to brown) exist in nature. In this work, we describe the design of blue melanin through the polymerization of Y-containing pentapeptides with two key properties: tight packing during peptide assembly and high solubility in aqueous environments. By motif scaffolding a pentapeptide-repeat protein (PRP) with RFdiffusion, we narrowed 160,000 possible combinations to a library of 905 Y-containing pentapeptides with tight packing features. Two of the most soluble designs successfully formed stable blue melanin with {lambda}max absorbing in 615-620 nm, contributed by homogeneous melanin length achieved around 60 Y units. Other designs also formed new colors (purple, green), along with more known colors (red, yellow, brown). We found that blue melanin exhibited thermal stability at an autoclave temperature of 121{degrees}C and photostability of weeks under 600 lux illumination. We also demonstrated the application of blue melanin as an electrophoretic ink. De novo color design from simple peptides could potentially transform how colorants are sourced and produced. Our approach with computational design should also inspire the development of new deep-learning tools to directly predict colors from amino acid sequences.

biochemistry↗

bioRxiv2024

Microbial lysates as low-cost serum replacements in cellular agriculture media formulation

Cultivated meat, the process of generating meat in vitro without sacrificing animals, is a promising alternative to the traditional practice of livestock agriculture. However, the success of this field depends on finding sustainable and economical replacements for animal-derived and expensive fetal bovine serum (FBS) that is typically used in cell culture processes. Here, we outline an effective screening process to vet the suitability of microbial lysates to support the growth of immortalized bovine satellite cells (iBSCs) and mackerel (Mack1) cells. We show that easily producible, low-cost whole-cell lysates from Vibrio natriegens can be used to create serum-free media for the long-term growth of iBSCs. The optimized medium, named "VN40" (basal B8 media containing Vibrio natriegens lysate proteins at 40 {micro}g/mL), outperforms previously established serum-free media while maintaining cell phenotype and myogenicity. Overall, this study shows a novel approach to producing serum-free media for cultivated meat production using microbially-derived lysates.

bioengineering↗