What Is: Synthetic Biology

Scientific Frontline: Extended "At a Glance" Summary: Synthetic Biology

The Core Concept: Synthetic biology is a transformative discipline that merges the biological sciences with rigorous, quantitative engineering principles to fundamentally redesign genetic sequences and construct entirely new biological parts, devices, and systems from the ground up.

Key Distinction/Mechanism: Unlike traditional "top-down" genetic engineering, which relies on retrofitting existing, naturally occurring cells by splicing or modifying small collections of genes, synthetic biology utilizes a predictable, "bottom-up" approach. It treats biology as an engineering discipline, building complex biological circuits and dynamic cellular functions entirely from scratch using rational design and computer science.

Major Frameworks/Components:

• Core Engineering Principles: The strict enforcement of standardization, modularity, and abstraction to bypass biological chaos and render cellular processes as predictable as microchip manufacturing.
• The Abstraction Hierarchy: A multi-tiered framework designed to manage biological complexity by intentionally hiding information across four levels: DNA (informational substrate), Bioparts/BioBricks (standardized sequences encoding isolated functions), Devices (assembled parts for specific tasks like logic gates), and complex Biological Systems functioning within a host cell "chassis."
• The Design-Build-Test-Learn (DBTL) Cycle: An iterative manufacturing workflow reliant on computer-aided design (CAD) and thermodynamic simulations (Design), automated gene synthesis and robotics (Build), high-throughput screening and multi-omics (Test), and artificial intelligence/machine learning for data parsing (Learn).

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.

UC Irvine scientists create powerful enzyme that quickly, accurately synthesizes RNA

“This work shows that enzymes are far more adaptable than we once thought,” says study leader John Chaput, UC Irvine professor of pharmaceutical sciences. “By harnessing evolution, we can create new molecular tools that open the door to advances in RNA biology, synthetic biology and biomedical innovation.”
Photo Credit: Steve Zylius / UC Irvine

Scientific Frontline: "At a Glance" Summary

• Main Discovery: Researchers engineered a novel DNA polymerase, designated C28, that efficiently synthesizes RNA with high fidelity and speed, a capability that natural DNA polymerases are biologically designed to reject.
• Methodology: The team utilized directed evolution within a high-throughput, single-cell screening platform to recombine related polymerase genes, evaluating millions of variants to identify unexpected structural solutions without manually redesigning the active site.
• Key Data: The C28 enzyme contains dozens of specific mutations selected from a pool of millions of variants, enabling it to operate at near-natural speeds while accommodating chemically modified RNA building blocks.
• Significance: This breakthrough overcomes fundamental biological barriers to RNA synthesis, creating a versatile tool that can also perform reverse transcription and generate hybrid DNA-RNA molecules using standard PCR techniques.
• Future Application: The enzyme provides critical functionality for developing next-generation mRNA vaccines and RNA-based therapeutics that require customized or chemically modified RNA sequences.
• Branch of Science: Biochemistry, Pharmaceutical Sciences, and Synthetic Biology.
• Additional Detail: Led by Professor John Chaput and published in Nature Chemical Biology, this research demonstrates that directed evolution can unlock molecular functions nonexistent in nature, such as the ability of a DNA polymerase to transcribe RNA.

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.

Scientists are taking major steps towards completing the world’s first synthetic yeast.

Photo Credit: Karyna Panchenko

A UK-based team of Scientists, led by experts from the University of Nottingham and Imperial College London, have completed construction of a synthetic chromosome as part of a major international project to build the world’s first synthetic yeast genome.

The work, which is published today in Cell Genomics, represents completion of one of the 16 chromosomes of the yeast genome by the UK team, which is part of the biggest project ever in synthetic biology; the international synthetic yeast genome collaboration.

The collaboration, known as 'Sc2.0' has been a 15-year project involving teams from around the world (UK, US, China, Singapore, UK, France and Australia), working together to make synthetic versions of all of yeast's chromosomes. Alongside this paper, another 9 publications are also released today from other teams describing their synthetic chromosomes. The final completion of the genome project - the largest synthetic genome ever - is expected next year.

Harnessing evolution: Evolved synthetic disordered proteins could address disease, antibiotic resistance

Yifan Dai and his team designed a method based on directed evolution to create synthetic intrinsically disordered proteins that can facilitate diverse phase behaviors in living cells. Intrinsically disordered proteins have different phase behaviors that take place at increasing or decreasing temperatures, as shown in the image above. The intrinsically disordered proteins on the left are cold responsive, and those on the right are hot responsive. The tree image in the center depicts the directed evolution process with the reversible intrinsically disordered proteins near the top. Feeding into the process from the bottom are soluble intrinsically disordered proteins.
Illustration Credit: Dai lab

The increased prevalence of antibiotic resistance could make common infections deadly again, which presents a threat to worldwide public health. Researchers in the McKelvey School of Engineering at Washington University in St. Louis have developed the first directed evolution-based method capable of evolving synthetic condensates and soluble disordered proteins that could eventually reverse antibiotic resistance.

Yifan Dai, assistant professor of biomedical engineering, and his team designed a method that is directed evolution-based to create synthetic intrinsically disordered proteins that can facilitate diverse phase behaviors in living cells. This allows them to build a toolbox of synthetic intrinsically disordered proteins with distinct phase behaviors and features that are responsive to temperatures in living cells, which helps them to create synthetic biomolecular condensates. In addition to reversing antibiotic resistance, the cells can regulate protein activity among cells. 

Scientists use quantum biology, AI to sharpen genome editing tool

ORNL scientists developed a method that improves the accuracy of the CRISPR Cas9 gene editing tool used to modify microbes for renewable fuels and chemicals production. This research draws on the lab’s expertise in quantum biology, artificial intelligence and synthetic biology.
Illustration Credit: Philip Gray/ORNL, U.S. Dept. of Energy

Scientists at Oak Ridge National Laboratory used their expertise in quantum biology, artificial intelligence and bioengineering to improve how CRISPR Cas9 genome editing tools work on organisms like microbes that can be modified to produce renewable fuels and chemicals.

CRISPR is a powerful tool for bioengineering, used to modify genetic code to improve an organism’s performance or to correct mutations. The CRISPR Cas9 tool relies on a single, unique guide RNA that directs the Cas9 enzyme to bind with and cleave the corresponding targeted site in the genome. Existing models to computationally predict effective guide RNAs for CRISPR tools were built on data from only a few model species, with weak, inconsistent efficiency when applied to microbes.

“A lot of the CRISPR tools have been developed for mammalian cells, fruit flies or other model species. Few have been geared towards microbes where the chromosomal structures and sizes are very different,” said Carrie Eckert, leader of the Synthetic Biology group at ORNL. “We had observed that models for designing the CRISPR Cas9 machinery behave differently when working with microbes, and this research validates what we’d known anecdotally.”

Tapping the engines of cellular electrochemistry and forces of evolution

Biological condensates are clumps of molecules that condense and scatter apart based on the surrounding chemical and electrical environment in a cell. Recent work from WashU researchers shows how to design and embed these proteins into living systems to serve as electron generators.
Image Credit: AI-generated image courtesy of Dai lab

Scientific Frontline: "At a Glance" Summary

• Main Discovery: Researchers successfully engineered "intrinsically disordered proteins" into biological condensates that function as nanoscale electrochemical "battery droplets" within living cells, capable of generating voltage and driving redox reactions.
• Methodology: The team utilized "directed evolution" in E. coli bacteria, subjecting protein sequences to selective pressures to guide the self-assembly of condensates that create interfacial electric fields similar to electrode-electrolyte boundaries in traditional batteries.
• Key Data: The engineered bio-batteries successfully drove the synthesis of gold and copper nanoparticles directly inside cells and executed redox reactions capable of killing bacteria without the use of traditional antibiotics.
• Significance: This establishes a new framework for "electrogenic protein powerhouses," proving that soft biological matter can store and release electrochemical energy on demand to power synthetic biological signals and reactions.
• Future Application: Applications include sustainable bioproduction, wastewater decontamination (via pollutant degradation), and "biohybrid" medical devices designed to fight infection or reverse antibiotic resistance.
• Branch of Science: Synthetic Biology, Biomedical Engineering, and Electrochemistry.
• Additional Detail: The study overcomes a significant hurdle in evolutionary biology by successfully applying directed evolution to non-structured (disordered) proteins, enabling the programmable design of cellular function based on survival and fitness.

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).

Computational Biology: In-Depth Description

Computational Biology is the interdisciplinary science that uses computational approaches, mathematical modeling, and algorithmic analysis to understand biological systems and relationships. Its primary goal is to extract meaningful insights from vast biological datasets—such as genetic sequences, protein structures, and cell signaling pathways—to simulate biological processes and predict outcomes in living systems.

Enzymes Can’t Tell Artificial DNA From the Real Thing

Like adding new letters to an existing language’s alphabet to expand its vocabulary, adding new synthetic nucleotides to the genetic alphabet could expand the possibilities of synthetic biology. This image shows a rendering of RNA polymerase (center) and a synthetic nucleotide (lower right).
Image Credit: UC San Diego Health Sciences

The genetic alphabet contains just four letters, referring to the four nucleotides, the biochemical building blocks that comprise all DNA. Scientists have long wondered whether it’s possible to add more letters to this alphabet by creating brand-new nucleotides in the lab, but the utility of this innovation depends on whether or not cells can actually recognize and use artificial nucleotides to make proteins.

Now, researchers at Skaggs School of Pharmacy and Pharmaceutical Sciences at the University of California San Diego have come one step closer to unlocking the potential of artificial DNA. The researchers found that RNA polymerase, one of the most important enzymes involved in protein synthesis, was able to recognize and transcribe an artificial base pair in exactly the same manner as it does with natural base pairs.

The findings, published in Nature Communications, could help scientists create new medicines by designing custom proteins.

Bioengineering: In-Depth Description

Bioengineering is an interdisciplinary field that applies engineering principles, design concepts, and quantitative methods to biological systems. It bridges the gap between engineering and the life sciences to create solutions for problems in biology, medicine, agriculture, and environmental science. Its primary goals are to analyze and understand complex biological systems and to develop new technologies, materials, and therapies to improve human health, quality of life, and sustainability.

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.

New biosensors shine a light on CRISPR gene editing

Detecting the activity of CRISPR gene editing tools in organisms with the naked eye and an ultraviolet flashlight is now possible using technology developed at the Department of Energy’s Oak Ridge National Laboratory.

Scientists demonstrated these real-time detection tools in plants and anticipate their use in animals, bacteria and fungi with diverse applications for biotechnology, biosecurity, bioenergy and agriculture. The team described the successful development of the UV system in Horticulture Research and their proof-of-principle demonstration in ACS Synthetic Biology.

CRISPR technologies have quickly become the primary tools of bioengineering, and new versions are continually in development. Identifying whether an organism has been modified by CRISPR technology was previously a complex and time-consuming process.

“Before this, the only way to tell if genome engineering occurred was to do a forensic analysis,” said Paul Abraham, a bioanalytical chemist and head of ORNL’s Secure Ecosystem Engineering and Design Science Focus Area. “To be successful, you would need to know what the genome looked like before it was rewritten. We wanted to design a platform where we could proactively observe CRISPR activity.”

The research team developed an efficient self-detect solution that takes advantage of the way CRISPR works to trigger the technology to reveal itself. Under normal conditions, CRISPR works by connecting with a short RNA sequence, known as the guide RNA, as it leads CRISPR to a matching DNA sequence. When the target DNA is found, CRISPR modifies the DNA by acting like tiny molecular scissors to cut through one or both strands of DNA, depending on the type of CRISPR technology in use.

Not only toxic but also a nutrient: guanidine as a nitrogen source

Cyanobacteria convert light energy into chemical energy through photosynthesis and are becoming increasingly important for carbon-neutral biotechnology.
Photo Credit: André Künzelmann / UFZ

Scientific Frontline: "At a Glance" Summary

• Main Discovery: Cyanobacteria possess the capability to actively absorb and catabolize guanidine (CH5N3) as their sole nitrogen source, refuting the prior scientific consensus that the compound acts exclusively as a toxic denaturant in these organisms.
• Methodology: The study utilized an interdisciplinary approach combining genome analysis, molecular microbiology, biochemical binding assays, and simulation-based process analytics to map the complete metabolic pathway and regulatory networks.
• Specific Mechanism: Uptake is facilitated by a newly identified, high-affinity ATP-binding cassette (ABC) transport system effective at low concentrations, while intracellular guanidine hydrolase converts the substrate into ammonium and urea for metabolic integration.
• Key Regulation Detail: Gene expression for the transporter and hydrolase is controlled by a specific riboswitch that directly binds guanidine, functioning as a precise sensor to regulate uptake and trigger efflux systems if intracellular levels become toxic.
• Ecological Context: These findings suggest that free guanidine is naturally available and constitutes an overlooked but integral component of global biogeochemical nitrogen cycles, providing a colonization advantage for cyanobacteria.
• Future Application: The identified riboswitch mechanism offers a novel, cost-effective molecular tool for synthetic biology, enabling researchers to finely tune gene expression in cyanobacterial "green cell factories" by modulating guanidine levels.

Researchers detect fluoride in water with new simple color change test

Photo Credit: Henryk Niestrój

Test is first to use artificial cell sensors to detect environmental contaminant

A team of synthetic biologists at Northwestern is developing a sensor platform that will be able to detect a range of environmental and biological targets in real-world samples.

Environmental contaminants like fluoride, lead and pesticides exist all around and even within us. While researchers have simple ways to measure concentrations of such contaminants inside lab environments, levels are much more difficult to test in the field. That’s because they require costly specialized equipment.

Recent efforts in synthetic biology have leveraged cellular biosensors to both detect and report environmental contaminants in a cost-effective and field-deployable manner. Even as progress is being made, scientists have struggled to answer the question of how to protect sensor components from substances that naturally exist in extracted samples.

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.

Nature’s photocopiers caught ‘doodling’ – and scientists say it could revolutionise how DNA is written

Nanoscale view of several interwoven fragments of ‘doodled’ DNA (orange and white strands) imaged on a near perfectly flat mica surface (shown in blue) using a custom high-speed atomic force microscope built at the University of Bristol.
Image Credit: Thomas Gorochowski

Scientific Frontline: Extended "At a Glance" Summary: DNA Polymerase "Doodling"

The Core Concept: DNA polymerases—the microscopic biological machines responsible for replicating DNA—possess an innate capability to synthesize entirely new, highly complex, and extensive DNA sequences from scratch without utilizing an existing template.

Key Distinction/Mechanism: Standard DNA replication relies on reading and mirroring an existing DNA strand. Conversely, "doodling" involves the autonomous generation of distinct genetic material ranging from simple two-base repeats to elaborate eight-base motifs. Furthermore, unlike contemporary chemical DNA synthesis, which is slow and limited to sequences of a few hundred bases, this template-free synthesis can generate fragments exceeding 85,000 bases in a single reaction. Crucially, the process can be "steered" by modulating environmental parameters, such as altering the temperature or restricting the available DNA building blocks.

Major Frameworks/Components: 

• Nanopore Sequencing: Utilized to map the full-length structures of thousands of autonomously generated DNA molecules, revealing unprecedented sequence complexity.
• Environmental Modulation: The methodology of altering reaction conditions (e.g., temperature shifts, reagent limitation) to dictate the specific repeating patterns and motifs synthesized by the polymerases.
• AI-Powered Protein Design: Proposed as an integrative framework to optimize and harness these biological machines for advanced, guided synthesis.

New advances to boost regeneration and plasticity of brain neurons

The study is led by Professor Daniel Tornero and researcher Alba Ortega , from the Faculty of Medicine and Health Sciences and the Institute of Neurosciences of the University of Barcelona
Photo Credit: Courtesy of University of Barcelona

The brain’s mechanisms for repairing injuries caused by trauma or degenerative diseases are not yet known in detail. Now, a study by the University of Barcelona describes a new strategy based on stem cell therapy that could enhance neuronal regeneration and neuroplasticity when this vital organ is damaged. The results reveal that the use of brain-derived neurotrophic factor (BDNF), combined with stem cell-based cell therapies, could help in the treatment of neurodegenerative diseases or brain injuries.

Combining cell therapy with BDNF production

BDNF is a protein that is synthesized mainly in the brain and plays a key role in neuronal development and synaptic plasticity. Several studies have described its potential to promote neuronal survival and growth, findings that are now extended by the new study.

“The findings indicate that BDNF can promote the maturation and increase the activity of neurons generated in the laboratory from donor skin cells. The skin cells must first be reprogrammed to become induced pluripotent stem cells (iPSCs), and then differentiated to obtain neuronal cultures,” says Daniel Tornero, from the UB’s Department of Biomedicine and the CIBER Area for the Neurodegenerative Diseases (CIBERNED).

In this way, the study combines cell therapy with the production of BDNF in the same cells. This study confirms the beneficial effects of this growth factor in neuronal cultures derived from human stem cells, the same cells that are used in cell therapy to treat, for example, stroke in animal models.

Bacteria upcycle carbon waste into valuable chemicals

Credit: Justin Muir

Bacteria are known for breaking down lactose to make yogurt and sugar to make beer. Now researchers led by Northwestern University and LanzaTech have harnessed bacteria to break down waste carbon dioxide (CO2) to make valuable industrial chemicals.

In a new pilot study, the researchers selected, engineered and optimized a bacteria strain and then successfully demonstrated its ability to convert CO2 into acetone and isopropanol (IPA).

Not only does this new gas fermentation process remove greenhouse gases from the atmosphere, it also avoids using fossil fuels, which are typically needed to generate acetone and IPA. After performing life-cycle analysis, the team found the carbon-negative platform could reduce greenhouse gas emissions by 160% as compared to conventional processes, if widely adopted.

The study was published in the journal Nature Biotechnology.

“The accelerating climate crisis, combined with rapid population growth, pose some of the most urgent challenges to humankind, all linked to the unabated release and accumulation of CO2 across the entire biosphere,” said Northwestern’s Michael Jewett, co-senior author of the study. “By harnessing our capacity to partner with biology to make what is needed, where and when it is needed, on a sustainable and renewable basis, we can begin to take advantage of the available CO2 to transform the bioeconomy.”

Jewett is the Walter P. Murphy Professor of Chemical and Biological Engineering at Northwestern’s McCormick School of Engineering and director of the Center for Synthetic Biology. He co-led the study with Michael Koepke and Ching Leang, both researchers at LanzaTech.