QIBEBT-led consortium achieves bacterial degradation of PET bottles to provide terephtalic acid in 97% yield

A research team from the Qingdao Institute of Bioenergy and Bioprocess Technology of the Chinese Academy of Sciences, in collaboration with Nanjing Tech University and Greifswald University, has introduced an innovative solution for the depolymerization of polyethylene terephthalate (PET). This solution utilizes an engineered whole-cell biocatalyst based on the thermophilic bacterium Clostridium thermocellum.

This study builds on prior work, where the research team first demonstrated the concept of whole-cell catalytic PET depolymerization. In that study, the genetically engineered C. thermocellum expressed leaf compost cutinase (LCC) via a plasmid for high-temperature PET depolymerization.

In this study, the researchers integrated LCC directly into the chromosome of C. thermocellum, ensuring stable enzyme expression. They further enhanced the system by introducing LCC variants and co-expressing hydrophobic modules.

By optimizing reaction conditions and controlling pH, the researchers achieved a significant improvement in PET depolymerization efficiency with minimal accumulation of the intermediate product mono(2-hydroxyethyl) terephthalate (MHET).

When tested with pretreated PET bottle particles, about 97% of the added PET was converted into terephthalic acid (TPA), a key monomer used in producing new plastics or high-value chemicals. This high level of performance positions the system as a promising green solution for PET recycling.

Additionally, C. thermocellum is naturally capable of degrading cellulose, making it a potential candidate for directly processing mixed textile waste that contains cotton fibers and PET.

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“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.

UNESCO endorses Green Carbon Programme to achieve sustainable development goals (SDGs)

http://english.qibebt.cas.cn/ne/rp/202512/t20251201_1134324.html

UNESCO’s “Decade of Sciences” aims to engage science in achieving its sustainable development goals (SDGs).

UNESCO has just endorsed the long-standing commitment of the Qingdao Institute of Bioenergy and Bioprocess Technology QIBEBT to providing open science solutions for green and sustainable technologies.

QIBEBT’s “Green Carbon Programme” focuses on four core themes,

development and utilization of green carbon resources,
green conversion and utilization of fossil carbon resources,
efficient fixation and utilization of carbon emissions, and
analysis and management of multi-scale carbon cycles.

In addition, QIBEBT operates the editorial office of the Green Carbon journal https://www.sciencedirect.com/journal/green-carbon which offers an in-depth and multidisciplinary view of research advances in the field.

With the leverage of the UNESCO endorsement, QIBEBT will boost its efforts to drive innovation and improve public science literacy, supporting high-quality, sustainable, and low-carbon development in China and worldwide for achieving the SDGs.

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.

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