Metabolic engineering of Yarrowia lipolytica for the production and secretion of the saffron ingredient crocetin.

Background: Crocetin is a multifunctional apocarotenoid natural product derived from saffron, holding significant promises for protection against various diseases and other nutritional applications. Historically, crocetin has been extracted from saffron stigmas, but this method is hindered by the limited availability of high-quality raw materials and complex extraction processes. To overcome these challenges, metabolic engineering and synthetic biology can be applied to the sustainable production of crocetin.

Designing synthetic microbial communities with the capacity to upcycle fermentation byproducts to increase production yields.

Microbial cell factories, which convert feedstocks into a product of value, have the potential to help transition toward a bio-based economy with more sustainable ways to produce food, fuels, chemicals, and materials. One common challenge found in most bioconversions is the co-production, together with the product of interest, of undesirable byproducts or overflow metabolites. Here, we designed a strategy based on synthetic microbial communities to address this issue and increase overall production yields.

Engineered cross-feeding creates inter- and intra-species synthetic yeast communities with enhanced bioproduction.

Microorganisms can be engineered to sustainably produce a variety of products including fuels, pharmaceuticals, materials, and food. However, highly engineered strains often result in low production yield, due to undesired effects such as metabolic burden and the toxicity of intermediates. Drawing inspiration from natural ecosystems, the construction of a synthetic community with division of labor can offer advantages for bioproduction.

Synthetic, marine, light-driven, autotroph-heterotroph co-culture system for sustainable β-caryophyllene production.

Applying low-cost substrate is critical for sustainable bioproduction. Co-culture of phototrophic and heterotrophic microorganisms can be a promising solution as they can use CO and light as feedstock. This study aimed to create a light-driven consortium using a marine cyanobacterium Synechococcus sp.

Modular Metabolic Engineering and Synthetic Coculture Strategies for the Production of Aromatic Compounds in Yeast.

Microbial-derived aromatics provide a sustainable and renewable alternative to petroleum-derived chemicals. In this study, we used the model yeast to produce aromatic molecules by exploiting the concept of modularity in synthetic biology. Three different modular approaches were investigated for the production of the valuable fragrance raspberry ketone (RK), found in raspberry fruits and mostly produced from petrochemicals.

Inducible expression of large gRNA arrays for multiplexed CRISPRai applications.

CRISPR gene activation and inhibition (CRISPRai) has become a powerful synthetic tool for influencing the expression of native genes for foundational studies, cellular reprograming, and metabolic engineering. Here we develop a method for near leak-free, inducible expression of a polycistronic array containing up to 24 gRNAs from two orthogonal CRISPR/Cas systems to increase CRISPRai multiplexing capacity and target gene flexibility. To achieve strong inducibility, we create a technology to silence gRNA expression within the array in the absence of the inducer, since we found that long gRNA arrays for CRISPRai can express themselves even without promoter.

Production of human milk fat substitute by engineered strains of .

Human milk fat has a distinctive stereoisomeric structure where palmitic acid is esterified to the middle (sn-2) position on the glycerol backbone of the triacylglycerol and unsaturated fatty acids to the outer (sn-1/3) positions. This configuration allows for more efficient nutrient absorption in the infant gut. However, the fat used in most infant formulas originates from plants, which exclude palmitic acid from the sn-2 position.

The Role of Hexokinase and Hexose Transporters in Preferential Use of Glucose over Fructose and Downstream Metabolic Pathways in the Yeast .

The development of efficient bioprocesses requires inexpensive and renewable substrates. Molasses, a by-product of the sugar industry, contains mostly sucrose, a disaccharide composed of glucose and fructose, both easily absorbed by microorganisms. , a platform for the production of various chemicals, can be engineered for sucrose utilization by heterologous invertase expression, yet the problem of preferential use of glucose over fructose remains, as fructose consumption begins only after glucose depletion what significantly extends the bioprocesses.

Advances in production of high-value lipids by oleaginous yeasts.

The global market for high-value fatty acids production, mainly omega-3/6, hydroxy fatty-acids, waxes and their derivatives, has seen strong development in the last decade. The reason for this growth was the increasing utilization of these lipids as significant ingredients for cosmetics, food and the oleochemical industries. The large demand for these compounds resulted in a greater scientific interest in research focused on alternative sources of oil production - among which microorganisms attracted the most attention.

A 37-amino acid loop in the Yarrowia lipolytica hexokinase impacts its activity and affinity and modulates gene expression.

The oleaginous yeast Yarrowia lipolytica is a potent cell factory as it is able to use a wide variety of carbon sources to convert waste materials into value-added products. Nonetheless, there are still gaps in our understanding of its central carbon metabolism. Here we present an in-depth study of Y.

Nitrogen as the major factor influencing gene expression in .

is an important industrial microorganism used for the production of oleochemicals. The design of effective biotechnological processes with this cell factory requires an in-depth knowledge of its metabolism. Here we present a transcriptomic study of grown in the presence of glycerol and glucose, and mixture of both at different carbon to nitrogen ratios.

Transforming sugars into fat - lipid biosynthesis using different sugars in Yarrowia lipolytica.

In an era of ever-increasing energy demands, a promising technology is being developed: the use of oleaginous microorganisms such as Yarrowia lipolytica to convert waste materials into biofuels. Here, we constructed two Y. lipolytica strains that displayed both increased lipid accumulation and more efficient use of biomass-derived sugars, including glucose, fructose, galactose and inulin.