A novel artificial carbon fixation pathway LATCH with 10 enzymatic steps

https://www.sciencedirect.com/science/article/pii/S2950155525000667?via%3Dihub

https://www.cas.cn/syky/202511/t20251125_5089765.shtml

A research team at the CAS Tianjin Institute of Industrial Biotechnology has proposed a novel artificial carbon fixation pathway—LATCH which comprises 10 completely known enzymatic steps. Each cycle converts two molecules of HCO₃⁻ into one molecule of acetyl-CoA, requiring only adenosine triphosphate (ATP) and reduced coenzyme II for energy. Kinetic and thermodynamic modeling analysis shows that it is a linear autocatalytic cycle structure without kinetic traps or thermodynamic barriers, possessing high feasibility and potential for continued development. It can provide insights for improving the efficiency of systems such as photosynthetic microorganisms, plants, and engineered cell factories.

Regarding the selection of parental modules, the research team referenced research on the serine cycle and designed a modified version of the serine cycle, simplifying the pathway structure and bypassing the inefficient steps involving hydroxypyruvate, thus enabling the pathway to function effectively in the heterologous host *E. coli*. Simultaneously, the team replaced the amino acid deamination and transamination steps in the serine cycle with a decarboxylation process, forming an MCG cycle free from formic acid dependence. This cycle can further convert glycerate 3-phosphate produced by processes such as the Calvin cycle and glycolysis into acetyl-CoA in a negative carbon mode. The study also referenced a series of photorespiration bypass concepts developed for recovering the Rubisco byproduct glycolate-2-phosphate, among which the TaCo module, due to its artificial carboxylation reaction, theoretically has a maximum yield of 150%. This study found that by introducing glyoxylate reductase as a key step to act as a “molecular latch,” the natural serine cycle and the artificially carboxylated module TaCo can be recombined, resulting in a functional transformation—from two parent modules dependent on organic substrates to a complete carbon-fixing cycle.

Based on the LATCH cycle formed by module integration, kinetic analysis shows that this pathway is a linear autocatalytic cycle, theoretically avoiding kinetic traps while eliminating the need to establish complex regulatory relationships. Meanwhile, eight steps in the pathway receive thermodynamic support from adenosine triphosphate (ATP), reducing power, or high-energy substrates, and the remaining two lyase-catalyzed processes do not pose thermodynamic bottlenecks. These inherent advantages at the stoichiometric, kinetic, and thermodynamic levels lay the foundation for the continued development and application of LATCH.

more insights

Green Carbon reaches a significant milestone: indexing in ESCI

https://www.sciencedirect.com/journal/green-carbon

The journal, founded only in 2023, has been formally accepted for indexing in the Emerging Sources Citation Index (ESCI), part of the Web of Science Core Collection by Clarivate. This achievement marks important recognition of the journal’s growing quality, editorial standards, and international relevance. ESCI inclusion will significantly enhance the journal’s visibility and provide authors with a broader platform for the dissemination of their research.

A wheelchair directed by the blinks of your eye…

https://j.people.com.cn/n3/2026/0203/c95952-20422094.html

A professor at Qingdao University in Shandong Province has developed a groundbreaking system that generates electricity when people blink, supplying power to glasses that allow patients with amyotrophic lateral sclerosis (ALS) to control their wheelchairs simply by moving their eyes.

With conventional eye tracking devices, patients who wanted to operate a wheelchair and move around had to wear a heavy device on their head and be connected to a long electrical cord. Furthermore, alarms of low battery levels did discouraging patients from moving around on their own.

The eye tracking system of the team generates and supplies electricity by attaching dimethylpolysiloxane (PDMS) to the surface of the user’s eyeball like a contact lens, creating a “micro-friction generator.” When the user blinks or moves their eyeball, friction occurs between the eyeball and PDMS, continuously generating electricity.

In an eyeglass frame worn by the user, transparent electrodes made of indium tin oxide are embedded, acting as a transducer. The transparent electrodes precisely track the distribution and changes of electric charge through electrostatic induction and convert it into a recognizable electrical signal in real time. This signal is then transmitted to an external device via a control circuit, ultimately enabling highly precise control.

Before this technology can leave the lab and be widely applied, however, a series of hurdles must be overcome for industrialization.

An illustration of controlling a wheelchair through blinking and eye movements (photo courtesy of interviewee).

“Ramanomics” simplify quality control in beer brewing – QIBEBT

https://doi.org/10.1016/j.biortech.2025.133788

http://english.cas.cn/newsroom/research_news/life/202601/t20260114_1145714.shtml

Breweries typically monitor fermentation by analyzing broth composition. Alcohols, esters, acids and residual sugars are quantified via chromatography-based assays. While reliable, these tests are time-consuming and only yield batch-average results.

A research led by scientists from the CAS Qingdao Institute of Bioenergy and Bioprocess Technology (QIBEBT) has simplified this process and developed a novel workflow dubbed “process ramanomics,” which is based on spontaneous single-cell Raman spectroscopy.

To validate the approach, the researchers tracked an industrial beer fermentation process using the lager yeast Saccharomyces pastorianus, sampling a single production batch over an eight-day period. At each stage of fermentation, they collected high-throughput Raman spectra from individual cells (a “ramanome”) and matched these unique molecular fingerprints to conventional lab measurements of 43 extracellular phenotypes in the fermentation medium.

Using multivariate regression analysis, the team found that ramanomes could accurately predict 19 extracellular phenotypes. This included four higher alcohols, four esters, four amino acids, two organic acids, four mono- and disaccharide substrates, and the alcohol-to-ester ratio—a commonly used indicator tied to beer flavor balance. In practical terms, a single, rapid cellular analysis can now replace multiple time-intensive chemical assays—without sacrificing single-cell resolution details.

Because the models output cell-level predictions, the researchers also tracked phenotypic heterogeneity over time. Different metabolite classes displayed distinct heterogeneity trajectories, and for several phenotypes higher heterogeneity tended to accompany lower metabolite levels—suggesting that dispersion among cells may be a useful process-state indicator.

Back to …

青岛 Qingdao
a hub for S&T