AIM: To explore the factors associated with significant corneal astigmatism during the perioperative period in patients with pterygium. METHODS: Patients with primary pterygium presenting at Shanxi Eye Hospital between February and June 2025 were enrolled. All patients underwent medical history collection. Pre- and postoperative data were obtained using Pentacam, anterior segment photography, Image J software, and anterior segment optical coherence tomography(AS-OCT). All patients underwent pterygium excision combined with autologous bulbar conjunctival flap transplantation under local infiltration anesthesia. RESULTS: A total of 76 patients(76 eyes)with pterygium were finally enrolled(30 males, 46 females)with a mean age of 62.2±8.2 y. The mean length of corneal invasion by pterygium was 3.61±0.89 mm, the mean depth of invasion into the anterior corneal surface was 0.15±0.09 mm, and the median area of corneal invasion was 10.25(6.90, 18.75)mm2. The median preoperative corneal astigmatism was 1.50(0.70, 5.45)D. Median astigmatism was 0.8(0.40, 1.28)D at 2 wk postoperatively and 0.60(0.30, 1.15)D at 1 mo postoperatively. Patient age showed a positive correlation with preoperative astigmatism, and with residual astigmatism at 2 wk and 1 mo postoperatively(all P<0.05). The length of corneal invasion was positively correlated with preoperative astigmatism and residual astigmatism at both postoperative timepoints(P<0.01). The depth of invasion showed no significant linear correlation with astigmatism at any stage(P=0.250, 0.761, 0.686). The area of corneal invasion was positively correlated with astigmatism at all stages(P<0.01). Patients were grouped based on significant astigmatism(≥1.0 D)and non-significant astigmatism(<1.0 D), after adjusting for other variables, age(P=0.031)and the area of corneal invasion(P=0.004)were identified as risk factors for significant astigmatism. Pterygium invasion length was not significant factors(P>0.05). Receiver operating characteristic(ROC)analysis showed the highest area under the curve(AUC)for the invasion area(AUC=0.915). CONCLUSION: Significant preoperative corneal astigmatism in pterygium patients is correlated with patient age, the length of corneal invasion, and the area of invasion. The area of pterygium invasion into the cornea is the strongest predictor of significant preoperative corneal astigmatism.

As important biocatalysts, nitrilases can efficiently convert nitrile groups into acids and ammonia in a mild and eco-friendly manner, being widely used in the synthesis of important pharmaceutical intermediates. Early studies reported that nitrilases only had the hydrolysis activity of catalyzing the formation of corresponding carboxylic acid products from nitriles, showing catalytic specificity. However, recent studies have shown that some nitrilases exhibit the hydration activity for catalyzing the formation of amides from nitriles, showing catalytic promiscuity. The catalytic promiscuity of nitrilases has dual effects. On the one hand, the presence of amide by-products increases the difficulties and costs of subsequent separation and purification of carboxylic acid products. On the other hand, however, if the catalytic reaction pathways of nitrilases can be precisely regulated to reshape enzyme functions, the reactions catalyzed by nitrilases can be broadened to provide new ideas for the biosynthesis of high-value amides, which is crucial for the development of artificial enzymes and biocatalysis. This review summarized the research progress in the catalytic promiscuity of nitrilases and discussed the key regulatory factors that may affect the catalytic promiscuity of nitrilases from the evolutionary origin, catalytic domains, and catalytic mechanisms, hoping to provide reference and inspiration for the application of nitrilases in biocatalysis.
Aminohydrolases/chemistry* ; Biocatalysis ; Nitriles/chemistry* ; Substrate Specificity ; Catalytic Domain ; Catalysis

In China, the crude oil supply is highly dependent on overseas countries, and thus strengthening crude oil self-sufficiency has become an important issue of the national energy security. Tertiary oil recovery, especially polymer flooding, has been widely applied in large oil fields in China, which can increase the recovery rate by 15%-20% compared with water flooding. However, the widely used oil flooding polymers show poor thermal stability and salinity tolerance, complicated synthesis ways of monomers, and environmental unfriendliness. Moreover, the polymer flooding induces problems including pore plugging, heterogeneity intensification, high dispersion of remaining oil resources, pressure rise in injection wells, and low efficiency circulation of injection medium, which restrict the subsequent recovery of old oil fields. Here, we systematically review the developing and current situations of polymer flooding, introduce the innovative biomanufacturing of oil flooding polymers and their monomers or precursors as well as low-cost bio-based chemical raw materials for multiple compound flooding. The comprehensive study of the relationships between microbial fermentation metabolites and polymer flooding will reveal the green and low-carbon paths for polymer flooding. Such study will enable the application of enzymes produced by microorganisms in polymer production and polymer plugging removal after polymer flooding as well as the application of microbial metabolites such as biosurfactants, organic acids, alcohols, biogas, and amino acids in enhancing oil recovery. This review suggests that incorporating biomanufacturing into polymer flooding will ensure the high productivity and stability for crude oil production in China.
Polymers/metabolism* ; China ; Petroleum ; Oil and Gas Fields

O-acetyl-L-homoserine (OAH) is a promising platform compound for the production of L-methionine and other valuable compounds, while its low yield and low conversion rate limit the industrial application. To solve these problems, we constructed a strain for high OAH production with the previously constructed L-homoserine producer Escherichia coli HS33 as the chassis by systematic metabolic engineering. Firstly, PEP accumulation, pyruvate utilization, and OAH synthesis pathway (overexpressing aspB, aspA, and thrA^C1034T) were enhanced to obtain an initial strain accumulating 13.37 g/L OAH. Subsequently, the co-factor synthesis genes were integrated to supply reducing power and energy, which increased the yield to 15.79 g/L. The OAH yield of the engineered strain OAH28 was further increased to 17.49 g/L by strengthening the acetic acid reuse pathway, improving the supply of acetyl-CoA, and regulating the expression of MetX from different sources. Finally, in a 5 L fermenter, OAH28 achieved an OAH titer of 47.12 g/L, with a glucose conversion rate of 32% and productivity of 0.59 g/(L·h). The results lay a foundation for increasing the OAH production by metabolic engineering and give insights into the industrial production of OAH.
Metabolic Engineering/methods* ; Escherichia coli/genetics* ; Homoserine/biosynthesis* ; Fermentation

Echinocandin B (ECB) is a key precursor of the antifungal drug anidulafungin. It is a secondary metabolite of Aspergillus nidulans, and its titer in fermentation is significantly affected by the ECB synthesis pathway and cell morphology. In this study, the key genes related to the transcription activation, hydroxylation, and cell morphology during ECB biosynthesis were investigated to increase the fermentation titer of ECB and to change the cell morphology of Aspergillus nidulans to reduce the viscosity of the fermentation broth. The results indicated that after overexpression of ecdB and ecdK, the ECB titer increased by 25.8% and 23.7%, respectively, compared with that of the wild-type strain, reaching (2 030.5±99.2) mg/L and (1 996.4±151.4) mg/L. However, the deletion of fksA associated with cell wall synthesis resulted in damage to the cell wall, affecting strain growth and product synthesis. The engineered strain overexpressing ecdB was fermented in a 50-L bioreactor, in which the ECB titer reached 2 234.5 mg/L. The findings laid a research foundation for the subsequent metabolic engineering of this strain.
Fermentation ; Aspergillus nidulans/genetics* ; Echinocandins/genetics* ; Bioreactors/microbiology* ; Fungal Proteins/biosynthesis* ; Metabolic Engineering

Synthetic biology is a crucial tool for the development of the bio-industry and bio-economy, representing a significant aspect of new quality productive forces. As a core course for graduate students in bioengineering, Synthetic Biology plays a vital role in ensuring the supply of essential talents for the development of the bio-industry in the new era. To better serve regional economic development and provide high-level talents for China's progress in the bio-industry, we analyzed typical issues encountered in the past teaching activities, set up a multi-disciplinary teaching team, optimized the course contents, adjusted the teaching mode, and mobilized students' learning interest. With the application of scientific research project as the starting point, we guided students to think and discuss deeply through the simulation of application writing and project defense, which improved students' critical thinking and innovative thinking. With industrialization as a focus, we explored a new training model combining production, education, and research through the joint practice base of the university and enterprises introduced typical cases of biomanufacturing to encourage students to engage in scientific research. The teaching reform significantly enhances the comprehensive abilities and national sentiments of graduate students. This paper hopes to serve as a reference for colleagues engaged in teaching in this field.
Synthetic Biology/education* ; Teaching ; China ; Humans

The Principle of Biotechnology is a compulsory course for undergraduates majoring in bioengineering at Zhejiang University of Technology. In response to the "Double First-Class" initiative and in order to improve the teaching effect of this course and the quality of talent training, we reformed the teaching of Principle of Biotechnology, the core course in bioengineering. Specifically, we reorganized the teaching contents, improved the process management of teaching and learning, and implemented multi-dimensional teaching practice. These measures improved teaching quality and promoted the achievement of training goals, which was of great significance for developing "First-Class" disciplines.
Biotechnology/education* ; Teaching ; China ; Curriculum ; Bioengineering/education* ; Universities

The development of synthetic biology has greatly promoted the construction of microbial cell factories, providing an important strategy for green and efficient chemical production. However, the bottleneck of poor tolerance to harsh industrial environments has become the key factor hampering the productivity of microbial cells. Adaptive evolution is an important method to domesticate microorganisms for a certain period by applying targeted selection pressure to obtain desired phenotypic or physiological properties that are adapted to a specific environment. Recently, with the development of technologies such as microfluidics, biosensors, and omics analysis, adaptive evolution has laid the foundation for efficient productivity of microbial cell factories. Herein, we discuss the key technologies of adaptive evolution and their important applications in improvement of environmental tolerance and production efficiency of microbial cell factories. Moreover, we looked forward to the prospects of adaptive evolution to realize industrial production by microbial cell factories.
Metabolic Engineering ; Industrial Microbiology/methods* ; Synthetic Biology ; Environment ; Industry

S-adenosyl-l-methionine (SAM) is ubiquitous in living organisms and plays important roles in transmethylation, transsulfuration and transamination in organisms. Due to its important physiological functions, production of SAM has attracted increasing attentions. Currently, researches on SAM production mainly focus on microbial fermentation, which is more cost-effective than that of the chemical synthesis and the enzyme catalysis, thus easier to achieve commercial production. With the rapid growth in SAM demand, interests in improving SAM production by developing SAM hyper-producing microorganisms aroused. The main strategies for improving SAM productivity of microorganisms include conventional breeding and metabolic engineering. This review summarizes the recent research progress in improving microbial SAM productivity to facilitate further improving SAM productivity. The bottlenecks in SAM biosynthesis and the solutions were also addressed.
S-Adenosylmethionine/metabolism* ; Plant Breeding ; Fermentation ; Metabolic Engineering

Tacrolimus (FK506) is a 23-membered macrolide with immunosuppressant activity that is widely used clinically for treating the rejection after organ transplantation. The research on tacrolimus production was mainly focused on biosynthesis methods, within which there are still some bottlenecks. This review summarizes the progress made in tacrolimus biosynthesis via modification of metabolic pathways and control of fermentation process, with the hope to address the technical bottlenecks for tacrolimus biosynthesis and improve tacrolimus production by fermentation engineering and metabolic engineering.
Tacrolimus ; Immunosuppressive Agents ; Fermentation ; Macrolides ; Anti-Bacterial Agents