The medium-temperature alpha-amylase of Bacillus amyloliquefaciens is widely used in the food and washing process. Enhancing the thermostability of alpha-amylases and investigating the mechanism of stability are important for enzyme industry development. The optimal temperature and pH of the wild-type BAA and mutant MuBAA (D28E/V118A/S187D/K370 N) were all 60 °C and 6.0, respectively. The mutant MuBAA showed better thermostability at 50 °C and 60 °C, with a specific activity of 206.61 U/mg, which was 99.1% greater than that of the wild-type. By analyzing predicted structures, the improving thermostability of the mutant MuBAA was mainly related to enhanced stabilization of a loop region in domain B via more calcium-binding sites and intramolecular interactions around Asp187. Furthermore, additional intramolecular interactions around sites 28 and 370 in domain A were also beneficial for improving thermostability. Additionally, the decrease of steric hindrance at the active cavity increased the specific activity of the mutant MuBAA. Improving the thermostability of BAA has theoretical reference values for the modification of alpha-amylases.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.bbrc.2023.02.064 | DOI Listing |
Bioorg Chem
January 2025
Department of Bioengineering, Gebze Technical University, 41400, Gebze, Kocaeli, Türkiye; BAUZYME Biotechnology Co., Gebze Technical University Technopark, 41400, Gebze, Kocaeli, Türkiye. Electronic address:
α-Amylases, constituting a significant share of the enzyme market, are mainly synthesized by the genus Bacillus. Enzymes tailored for specific industrial applications are needed to meet the growing demand across a range of industries, and thus finding new amylases and optimizing the ones that already exist are extremely important. This study reports the successful expression, characterization and immobilization of P.
View Article and Find Full Text PDFInt J Mol Sci
December 2024
Department of Biomedical Sciences, College of Medicine, Korea University, Seoul 02841, Republic of Korea.
The protein therapeutics market, including antibody and fusion proteins, has experienced steady growth over the past decade, underscoring the importance of optimizing amino acid sequences. In our previous study, we developed a fusion protein, R31, which combines retinol-binding protein (RBP) with albumin domains IIIA and IB, linked by a sequence (AAAA), and includes an additional disulfide bond (N227C-V254C) in IIIA. This fusion protein effectively inhibited hepatic stellate cell activation.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
College of Bioscience and Bioengineering, Fuzhou University, Fuzhou 360105, China. Electronic address:
Baeyer-Villiger monooxygenases (BVMOs) can catalyze the asymmetric sulfoxidation to form pharmaceutical prazoles in environmentally friendly approach. In this work, the thermostable BVMO named PockeMO had high sulfoxidation activity towards rabeprazole sulfide to form (R)-rabeprazole but demonstrated significant overoxidation activity to form undesired sulfone by-product. To address this issue, the enzyme was engineered based on the computer assisted comparison for the substrate binding conformations.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
College of Biological Engineering, Sichuan University of Science and Engineering, Yibin, Sichuan 644005, China. Electronic address:
Cellulose-based paper is inherently poor in hydrophobicity and mechanical strength, limiting its practical applications in daily life such as packaging materials, water-resistant labels, and disposable tableware. This study aimed to develop an effective and eco-friendly strategy to address these limitations by enhancing the hydrophobicity and mechanical properties of cellulose paper. To achieve this, an internal sizing agent was prepared by combining (3-glycidoxypropyl) trimethoxy (GPS) with natural rosin.
View Article and Find Full Text PDFVaccines (Basel)
December 2024
Laboratory of Molecular Studies and Experimental Therapy-LEMTE, Department of Genetics, Federal University of Pernambuco, Recife 50670-901, Brazil.
Background/objectives: DNA vaccines are rapidly produced and adaptable to different pathogens, but they face considerable challenges regarding stability and delivery to the cellular target. Thus, effective delivery methods are essential for the success of these vaccines. Here, we evaluated the efficacy of capsules derived from the cell wall of the yeast as a delivery system for DNA vaccines.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!