Engineered yeast gives the U.S. a green edge in the critical minerals market

Researchers genetically engineered the metabolic pathways in yeast to produce oxalic acid, which can be used to extract free rare earth elements from low-grade ore.
Graphic Credit: Courtesy Dan Herchek/LLNL

Scientific Frontline: Extended "At a Glance" Summary: Engineered Yeast for Rare Earth Element Recovery

The Core Concept: A novel, environmentally sustainable biomanufacturing process that utilizes genetically engineered yeast to produce oxalic acid, which is subsequently used to extract and purify free rare-earth elements (REEs) from low-grade ore.

Key Distinction/Mechanism: Conventional oxalic acid production relies on strong acids and generates environmentally hazardous byproducts. In contrast, this new method employs a low-pH-tolerant yeast strain (Issatchenkia orientalis) with modified metabolic pathways to convert glucose directly into oxalic acid. The resulting fermentation broth acts as an oxidizer that selectively binds to REEs, precipitating them into a solid state with over 99% efficiency while leaving unwanted "junk" metals (like zinc) dissolved in solution.

Origin/History: It was developed through a collaboration between the University of Illinois Urbana-Champaign, Lawrence Livermore National Laboratory (LLNL), and the University of Kentucky, in response to a Defense Advanced Research Projects Agency (DARPA) solicitation aimed at utilizing environmental microbes as bioengineering resources.

Programmable proteins use logic to improve targeted drug delivery

Therapies that are sensitive to multiple biomarkers could allow medicines to reach only the areas of the body where they are needed. The diagram above shows three theoretical biomarkers that are present in specific, sometimes overlapping areas of the body. A therapy designed to find the unique area of overlap between the three will act on only that area.
Image Credit: DeForest et al./Nature Chemical Biology

Targeted drug delivery is a powerful and promising area of medicine. Therapies that pinpoint the exact areas of the body where they’re needed — and nowhere they’re not — can reduce the medicine dosage and avoid potentially harmful “off target” effects elsewhere in the body. A targeted immunotherapy, for example, might seek out cancerous tissues and activate immune cells to fight the disease only in those tissues.

The tricky part is making a therapy truly “smart,” where the medicine can move freely through the body and decide which areas to target.

Rice scientists reengineer cancer drugs to be more versatile

Rice University scientists have enlisted widely used cancer therapy systems to control gene expression in mammalian cells, a feat of synthetic biology that could change how diseases are treated.
Photo Credit: Jeff Fitlow/Rice University

Scientific Frontline: Extended "At a Glance" Summary: Engineered PROTAC-CID Systems

The Core Concept: Proteolysis targeting chimeras (PROTACs), highly specific small molecules traditionally used as cancer therapies, have been reengineered by scientists to function as genetic switches that precisely control and induce gene expression in mammalian cells.

Key Distinction/Mechanism: While standard PROTACs function by targeting specific oncogenic proteins and flagging them for targeted degradation, this novel approach repurposes their molecular infrastructure to achieve chemically induced dimerization (CID). In this reengineered system, the small molecules act as inducers that bind two proteins together to turn targeted gene expression on or off, granting unprecedented spatial and temporal control over genetic activation rather than destroying the target protein.

Major Frameworks/Components:

• PROTACs (Proteolysis Targeting Chimeras): Small molecules traditionally utilized to target and disintegrate harmful, disease-causing proteins without prompting drug resistance.
• Chemically Induced Dimerization (CID): A biological mechanism in which two distinct proteins bind together exclusively in the presence of a specific third molecule, known as an inducer.
• Temporal and Spatial Control: A regulatory framework where the natural metabolization of small molecules dictates the duration of gene expression (temporal), and localized delivery restricts activity to specific organs to prevent systemic toxicity (spatial).

Pioneering research using bacteria brings scientists a step closer to creating artificial cells with lifelike functionality

Amoeba-shaped bacteriogenic protocell: membrane (red boundary); nucleus (blue); cytoskeleton (red filaments); vacuole (red circle); ATP production (green). Scale bar, 5 μm.
Credit: Professor Stephen Mann and Dr Can Xu

Scientific Frontline: Extended "At a Glance" Summary: Bacteriogenic Protocells

The Core Concept: Bacteriogenic protocells are advanced synthetic cells constructed by trapping live bacteria within and upon viscous micro-droplets. These structures successfully mimic real-life cellular functionality by utilizing retained bacterial components to produce energy and synthesize proteins.

Key Distinction/Mechanism: While previous attempts to model protocells relied on empty microcapsules with limited capabilities, this approach utilizes a living-material assembly process. By incorporating two types of bacteria into micro-droplets and subsequently destroying them, the process leaves behind thousands of active biological molecules, genetic machinery, and cellular parts integrated directly into the membrane and interior of the synthetic cell.

Major Frameworks/Components: 

• Micro-Droplet Assembly: The foundational step where one population of bacteria is spontaneously captured within viscous droplets while another is trapped at the surface.
• Structural Remodeling: The targeted destruction of the bacteria, which releases components that condense into a single nucleus-like structure, a cytoskeletal-like network of protein filaments, and membrane-bounded water vacuoles.
• Self-Sustainable Energization: The implantation of living bacteria into the protocells to drive self-sustaining ATP production (via glycolysis), ongoing in vitro gene expression, and cytoskeletal assembly.
• Bionic Integration: The resulting cellular bionic system adopts an amoeba-like external morphology driven by on-site bacterial metabolism and growth.

Pathways to production

A graphic illustration of the kind of retrosynthetic analysis conducted by RetSynth software developed at Sandia National Laboratories. Using a novel algorithm, the software identifies the biological or chemical reactions needed to create a desired biological product or compound.
(Graphic by Laura Hatfield)

Scientific Frontline: "At a Glance" Summary: Pathways to Production

• Main Discovery: Biologists at Sandia National Laboratories developed a stand-alone software program called RetSynth that uses a novel algorithm to sort through large, curated databases of biological and chemical reactions.
• Methodology: The platform employs retrosynthetic analysis to map out the biological and chemical steps required to engineer and modify cellular molecules, rapidly evaluating all possible production pathways to determine the most efficient sequences.
• Key Data: The software algorithm optimizes manufacturing routes based on specific metrics: the fewest required steps, the highest economic viability utilizing available resources, and the maximum achievable theoretical yield of the desired bioproduct.
• Significance: This technology substantially accelerates the traditionally slow research and development process for bioproduction by rendering clear visual pathways and offering customizable biological, chemical, or hybrid production options.
• Future Application: The software is being commercially licensed to dramatically reduce manufacturing waste and emissions while producing next-generation therapeutics, biofuels, industrial chemicals, cosmetics, and agricultural compounds.
• Branch of Science: Synthetic Biology, Computational Biology, Bioengineering.