Article
Biochemistry & Molecular Biology
Yasuhiro Nonaka, Takashi Ogawa, Hiroki Shoji, Nozomu Nishi, Shigehiro Kamitori, Takanori Nakamura
Summary: This study elucidated the key residues for carbohydrate specificity of Xenopus laevis skin galectin xgalectin-Va through site-directed mutagenesis, leading to a successful change in carbohydrate selectivity. The mutation of two amino acids greatly enhanced the binding ability to N-acetyllactosamine and conferred significant T-cell growth inhibition activity. The loop substitution also successfully altered the carbohydrate selectivity of xgalectin-Va and xgalectin-Ib.
BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS
(2021)
Article
Biochemistry & Molecular Biology
Mohammed Hamed Alqarni, Ahmed Ibrahim Foudah, Magdy Mohamed Muharram, Haritium Budurian, Nikolaos E. Labrou
Summary: AMPS-HDB reacts covalently with CbFDH, leading to complete inactivation of the enzyme activity, while NAD(+) and NADH protect CbFDH from inactivation by AMPS-HDB. Molecular modelling studies identified Arg174 as the target for AMPS-HDB, confirmed by site-directed mutagenesis.
Article
Behavioral Sciences
Laura E. Martin, Juyun Lim
Summary: This study investigated the effects of the cyclic form and degree of polymerization on the taste perception of oligosaccharides. The findings suggest that cyclodextrins can activate the human sweet taste receptor.
Article
Biochemistry & Molecular Biology
Nicolas Hedin, Maria B. Velazquez, Julieta Barchiesi, Diego F. Gomez-Casati, Maria Busi
Summary: The study identified CBM20CP as a plastidial protein regulating starch synthesis in the green alga Ostreococcus tauri. It can bind starch, amylose, and amylopectin with different affinities, and interacts with other proteins to promote starch granule growth and catalytic efficiency.
PLANT MOLECULAR BIOLOGY
(2022)
Article
Agriculture, Multidisciplinary
Yi-Yu Chen, Meng-Si Li, Xiao Yun, Fei Xia, Meng-Jun Hu, Tengchuan Jin, Min-Jie Cao, Dong Lai, Guixia Chen, Guang-Ming Liu
Summary: Site-directed mutations were utilized to reduce the immunoreactivity of sarcoplasmic calcium-binding protein (SCP) by replacing key amino acids in conformational epitopes and calcium-binding sites. The mutant SCPs effectively inhibited the binding with wild-type SCP and downregulated the expression levels of CD63 and CD203c on basophil surface, indicating impaired calcium binding ability and reduced immunoreactivities. This approach showed potential for application in reducing immunoreactivities of other shellfish allergens.
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
(2021)
Article
Chemistry, Applied
Roberto Aguado, Dina Murtinho, Artur J. M. Valente
Summary: The study demonstrates the long-lasting protection of antioxidant and antimicrobial compounds loaded on polysaccharide substrates, effectively preserved by cyclodextrin moieties, to confer specific properties to fabrics, paper and other materials. The insertion of beta-cyclodextrin units enhances the long-term retention of phenolic active compounds in carbohydrate matrices, with a higher percentage of compound retained when using certain substrates. The release rate of these compounds over time can be measured and fitted to kinetic models to predict their behavior in aqueous ethanol.
CARBOHYDRATE POLYMERS
(2021)
Article
Microbiology
Emily C. Hoedt, Francesca Bottacini, Nora Cash, Roger S. Bongers, Kees van Limpt, Kaouther Ben Amor, Jan Knol, John MacSharry, Douwe van Sinderen
Summary: Members of the genus Bifidobacterium are difficult to genetically manipulate due to their extensive and variable Restriction-Modification systems. A modified suicide vector, pFREM28, was developed to target specific genes in B. breve by removing known restriction sites, reducing the time, effort, and resources required for generating site-directed mutants. This approach could be applied to other (bifido)bacterial species as well.
FRONTIERS IN MICROBIOLOGY
(2021)
Article
Agriculture, Multidisciplinary
Su-Jin Jun, Jung-A Lee, Young-Wan Kim, Sang-Ho Yoo
Summary: Through site-directed mutagenesis, a robust mutant Bifidobacterium thermophilum (BtAS) strain BtAS(Y414F/P200R) with enhanced turanose productivity was successfully developed, showing an increase in turanose yield by two times compared to the wild type BtAS and completing the reaction in half the time.
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Soroosh Pouyan, Milad Lagzian, Mohammad Hossein Sangtarash
Summary: This study characterized a new alpha-amylase from Bacillus cereus GL96 and used an in-silico approach to redesign the enzyme for improved thermal stability. The engineered enzyme showed higher stability and activity at elevated temperatures compared to the wild-type enzyme. Specifically, the D162K mutation resulted in the best performance, with increased optimum temperature and improved stability. This mutant enzyme holds promise for further investigation and industrial applications.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2022)
Article
Plant Sciences
Xia Li, Geng Chen, Qing-Qing Gao, Chun-Fan Xiang, Cheng-Xiao Yuan, Xiao-Ning Li, Yan-Yu Shu, Guang-Hui Zhang, Yan-Li Liang, Sheng-Chao Yang, Chen-Xi Zhai, Yan Zhao
Summary: This study explored the key enzymes involved in cucurbitacins biosynthesis in the Chinese traditional medicinal plant Hemsleya chinensis. Using AlphaFold2 and molecular docking, the researchers successfully predicted the 3D structure of HcOSC6 and its binding features to 2,3-oxidosqualene. Mutagenesis experiments identified three key amino acid residues, E246, M261, and D490, which significantly affected the activity of HcOSC6. This study not only characterized three potential key residues for producing cucurbitacins, but also provided insights into their significant role in metabolic engineering.
FRONTIERS IN PLANT SCIENCE
(2023)
Article
Biochemistry & Molecular Biology
Waraporn Auiewiriyanukul, Wataru Saburi, Tomoya Ota, Jian Yu, Koji Kato, Min Yao, Haruhide Mori
Summary: The study found that the Asn258 mutants of BspAG13_31A have significant impacts on the structure and function of the enzyme. N258G/P mutations enhance trisaccharide specificity, the N258P mutation also enhances activity towards sucrose and produces erlose through transglucosylation. N258G shows a higher specificity for transglucosylation with p-nitrophenyl alpha-D-glucopyranoside and maltose.
Article
Biochemistry & Molecular Biology
Lena Goshayeshi, Sara Yousefi Taemeh, Nima Dehdilani, Mohammadreza Nasiri, Mohammad M. Ghahramani Seno, Hesam Dehghani
Summary: The study demonstrates the use of an RNA-guided piggyBac transposase and dual sgRNAs for site-directed integrations in the human ROSA26 safe harbor region. This methodology shows promise for targeting specific genomic regions, such as in cancer cells for inserting sequences into target regions or activating tumor suppressor genes.
Article
Agriculture, Multidisciplinary
Cheng-Hua Wang, Wu-Ping Xiong, Cheng Huang, Xiao-Ming Li, Qing-Yan Wang, Ri-Bo Huang
Summary: This study successfully increased the catalytic activity and efficiency of an exoinulinase under acidic conditions through rational site-directed mutagenesis. The mutants showed improved substrate preference for inulin and may serve as promising candidates for industrial inulin hydrolysis. The study demonstrates the potential of mutating non-conserved substrate recognition residues for industrial enzyme improvements.
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE
(2021)
Review
Plant Sciences
Olawale Samuel Adeyinka, Bushra Tabassum, Brice Landry Koloko, Ifedayo Victor Ogungbe
Summary: The improvement of CRISPR-Cas gene editing technology has facilitated genetic modification of desirable agronomic traits in crops, such as resistance to pathogens, drought tolerance, nutritional value, and yield-related traits. This presents a significant opportunity for precise genetic diversification in plants.
Article
Biochemistry & Molecular Biology
Satoru Watanabe, Masahiro Ito, Takanori Kigawa
Summary: DiRect is a novel PCR-based mutagenesis method that achieves high quality product (>99% substitution) without the use of recombinant DNA technology. It has been successfully applied in the study of an industrially relevant enzyme, showing simplicity, efficiency, and potential scalability in site-directed mutagenesis.
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
(2021)
Article
Biochemistry & Molecular Biology
Stefan Jarl Christensen, Michael Schmidt Madsen, Signe Schram Zinck, Christinne Hedberg, Ole Bandsholm Sorensen, Birte Svensson, Anne S. Meyer
Summary: 4-alpha-glucanotransferase mediated glucan transfer allows for the production of clean label starch ingredients with unique gelling properties. Researchers have studied six different GH77 members and found that four of them exhibit starch modifying activity, leading to a decrease in amylose content, elongation of amylopectin chains, and the formation of firm starch gels. The enzyme Tt4 alpha GT from Thermus thermophilus showed the highest temperature optimum (73 degrees C) and the best potato starch modifying efficacy compared to the other enzymes.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2023)
Article
Biochemistry & Molecular Biology
Yu Wang, Yazhen Wu, Stefan Jarl Christensen, Stefan Janecek, Yuxiang Bai, Marie Sofie Moller, Birte Svensson
Summary: In this study, a thermophilic 4-alpha-glucanotransferase was engineered by fusing starch binding domains (SBDs) to enhance its affinity for starch, leading to increased activity and stability.
Article
Biochemistry & Molecular Biology
Mikkel Madsen, Andreas Prestel, Eva Madland, Peter Westh, Anne Tondervik, Havard Sletta, Gunther H. J. Peters, Finn L. L. Aachmann, Birthe B. B. Kragelund, Birte Svensson
Summary: In order to improve the control of biomaterial property design, a better understanding of the complex coacervation between anionic polysaccharides and proteins is essential. This study investigated the initial steps of condensate formation between beta-lactoglobulin A (beta-LgA) and various alginate oligosaccharides (AOSs), providing structural details of their multivalent interactions. The results revealed that beta-LgA exhibited high multivalency and showed similar affinities for AOSs with increasing degree of polymerization. NMR analyses identified different binding sites for AOSs on beta-LgA, and molecular docking indicated that the AOSs have similar orientations at the preferred binding site. The study highlights the dynamic nature of the AOS binding and its role in the formation of disordered beta-LgA alginate coacervate structures.
Article
Food Science & Technology
Xiaoxiao Li, Danni Zheng, Jing Wu, Zhengyu Jin, Birte Svensson, Yuxiang Bai
Summary: Poor thermostability of gamma-CGTase restricts its application in starch utilization and gamma-CD yield. By adding Ca2+ and conducting site-directed mutagenesis, the thermostability of Bacillus sp. FJAT-44876 gamma-CGTase (BF gamma-CGTase) was improved. The addition of 10 mM Ca2+ increased the half-life (t1/2) at 55 and 60 degrees C from 3.0 to 0.3 h to 17.4 and 2.0 h, respectively. Ca2+ stabilized the tertiary structure of BF gamma-CGTase, leading to improved thermostability. A mutation to serine in an alpha-helix glycine residue also enhanced stability, especially at higher temperatures. Furthermore, the G208S mutant in the presence of 10 mM Ca2+ exhibited increased t1/2 and yield of gamma-CD production from tapioca starch. This study highlights the importance of rational protein engineering in enhancing enzymatic gamma-CD production.
Article
Chemistry, Applied
Yixi Liu, Yazhen Wu, Hangyan Ji, Xiaoxiao Li, Zhengyu Jin, Birte Svensson, Yuxiang Bai
Summary: A cost-effective enzymatic process for the synthesis of Isomalto/malto-polysaccharides (IMMPs) was developed using cyclodextrinase and GtfB-Delta N to convert beta-cyclodextrin into IMMPs. The yield reached 16.19% (w/w) and the average DP of IMMPs could be controlled by adjusting the substrate composition.
CARBOHYDRATE POLYMERS
(2023)
Article
Chemistry, Applied
Yazhen Wu, Xiaoxiao Li, Zhengyu Jin, Birte Svensson, Yuxiang Bai
Summary: How to improve the solubility of linear dextrins (LD) without adding new chemical groups has been explored in this study by attaching a flexible glucochain at the reducing end to create a single-arm linear dextrin (SLD). The synthesis involved extending glucose units onto sucrose and subsequently extending the glucochain with gamma-CD. SLD demonstrated significantly improved solubility and dispersibility of resveratrol in water, providing a new strategy for addressing the solubility problem of LD and potential design of starch-like materials.
CARBOHYDRATE POLYMERS
(2023)
Review
Biochemistry & Molecular Biology
Yu Tian, Yu Wang, Yuyue Zhong, Marie Sofie Moller, Peter Westh, Birte Svensson, Andreas Blennow
Summary: Enzymatic hydrolysis of starch granules is fundamental for understanding starch degradation in plant cells, utilizing starch as an energy resource in foods, and developing efficient saccharification processes. However, the kinetics of hydrolysis for solid substrates like starch granules are slower and more complex. The multifaceted nature of the substrate surface and its changing properties during hydrolysis pose challenges for analysis.
Article
Biochemistry & Molecular Biology
Malene Bech Vester-Christensen, Jesper Holck, Martin Rejzek, Lea Perrin, Morten Tovborg, Birte Svensson, Robert A. Field, Marie Sofie Moller
Summary: A study found that the enzyme HvLD from barley showed a preference for pNP maltoside as both acceptor and donor, and exhibited excellent activity when pullulan or its fragment was used as the donor. In addition, HvLD could use a-maltosyl fluoride as a donor and maltose as the best acceptor. The findings provide insights for the production of glycoconjugate compounds with novel glycosylation patterns using natural donors.
Article
Biochemistry & Molecular Biology
Jinxing Zhai, Xiaoxiao Li, Birte Svensson, Zhengyu Jin, Yuxiang Bai
Summary: In this study, rice flour (RF) with higher protein content was prepared using a granular starch hydrolyzing enzyme (GSHE). The hydrolytic mechanism of RF and rice starch (RS) was established through characterization of particle size, morphology, crystallinity, and molecular structures. Processability of RF was evaluated through thermal, pasting, and rheological properties. The GSHE treatment resulted in sequential hydrolysis of crystalline and amorphous areas on the starch granule surface, leading to changes in amylose content and protein content in RF. However, the processability of RF was properly maintained.
Article
Biochemistry & Molecular Biology
Agnes B. Petersen, Seyed Hossein Mirbarati, Birte Svensson, Jens O. Duus, David Teze
Summary: Engineering glycoside hydrolases is an important approach for obtaining catalysts that can form glycosidic bonds. In this study, an engineered enzyme called TtOGA-D120N from the GH84 family was shown to be an efficient O-, N-, and S-glycoligase, capable of using various nucleophiles. The enzyme also catalyzes the formation and release of an activated intermediate, which allows for cascade synthesis in combination with transglycosylases or glycosynthases, as demonstrated by the synthesis of a specific human milk oligosaccharide lacto-N-triose II.
Article
Medical Laboratory Technology
Annika Hummersgaard Hansen, Helene Wallem Breisnes, Thomas Skovhus Prior, Ole Hilberg, Daniel Guldager Kring Rasmussen, Federica Genovese, Marie Vestergaard Lukassen, Birte Svensson, Lasse L. ocke Langholm, Tina Manon-Jensen, Morten Asser Karsdal, Diana Julie Leeming, Elisabeth Bendstrup, Jannie Marie Billow Sand
Summary: This study developed the FN-EDB assay for the serological assessment of MMP-8 degradation of EDB in cellular FN. It found that the degradation of EDB in cellular FN is elevated in IPF patients and further investigation is warranted.
CLINICAL BIOCHEMISTRY
(2023)
Article
Biochemistry & Molecular Biology
Moez Rhimi, Jean-Luc Da Lage, Richard Haser, Georges Feller, Nushin Aghajari
Summary: Insects rely on carbohydrates like starch and glycogen for energy, and α-amylases play essential roles under extreme conditions, contributing to their survival. Drosophila melanogaster α-amylase, DMA, is active over a broad temperature and pH range, and its crystal structures reveal an adaptive response to temperature variations.
Article
Agriculture, Multidisciplinary
Yu Wang, Yu Tian, Yuyue Zhong, Mohammad Amer Suleiman, Georges Feller, Peter Westh, Andreas Blennow, Marie Sofie Moller, Birte Svensson
Summary: Degradation of starch granules can be increased by fusing the psychrophilic a-amylase AHA from Antarctic bacterium Pseudoalteromonas haloplanktis TAB23 with starch-binding domains (SBD) from either Aspergillus niger glucoamylase (SBDGA) or Arabidopsis thaliana glucan, water dikinase 3 (SBDGWD3). The fusion enzymes showed higher activity than the wild-type AHA, depending on the starch type and source. The increased density of enzyme attack-sites and binding-sites on the starch granules was measured using an interfacial catalysis approach.
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
(2023)
Article
Chemistry, Physical
Mikkel Madsen, Hossein Mohammad-Beigi, Peter Westh, Finn L. Aachmann, Birte Svensson
Summary: The complex coacervation between alginate and beta-lactoglobulin can be controlled by pH and temperature, making it suitable for different purposes. Detailed characterization of the coacervation process and particles provides insights into molecular interactions and the effects of external factors. These findings have implications for microencapsulation and drug delivery.
Article
Biotechnology & Applied Microbiology
Henriette Lyng Roder, Eleni Christidi, Cristina I. Amador, Samra Music, Asmus Kalckar Olesen, Birte Svensson, Jonas Stenlokke Madsen, Jakob Herschend, Jan-Ulrich Kreft, Mette Burmolle
Summary: The study revealed that flagella play a significant role in impacting plasmid transfer and uptake in bacterial biofilms, with mechanisms such as steric hindrance of pilus movement and binding reducing the frequency of contact and plasmid uptake. This finding adds a new layer of complexity to understanding bacterial conjugation in biofilms beyond traditional factors like distance and lag times.
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
(2023)