Review
Chemistry, Physical
Zhongbin Xiao, Ming Sun, Tang Li, Miao Zhao, Heng Yin
Summary: Mannuronan C-5 epimerases (ManC5-Es) are key enzymes that convert beta-D-mannuronic acid (M) to alpha-L-guluronic acid (G) in alginate. They have different patterns of activity and are important for modifying alginate for various industrial applications. This review focuses on the methods of ManC5-Es activity assay, characterization of ManC5-Es from different sources, and the catalytic mechanism of ManC5-Es based on resolved enzyme structures. It also discusses potential future research directions.
Article
Plant Sciences
Anne Tondervik, Randi Aune, Adelheid Degelmann, Michael Piontek, Helga Ertesvag, Gudmund Skjak-Braek, Havard Sletta
Summary: Alginates, linear polysaccharides produced by brown algae and bacteria, have various applications in industrial, medical, and pharmaceutical fields. This study investigates the potential of using H. polymorpha for large-scale production of alginate epimerases. The results suggest that H. polymorpha is a suitable host organism for this purpose.
FRONTIERS IN PLANT SCIENCE
(2022)
Review
Biochemistry & Molecular Biology
Agnes Beenfeldt Petersen, Anne Tondervik, Margrethe Gaardlos, Helga Ertesvag, Havard Sletta, Finn Lillelund Aachmann
Summary: Alginate, a polysaccharide derived from brown algae and bacteria, has various industrial and pharmaceutical applications due to its gelling and viscosifying properties. Alginate can be modified by enzymes such as lyases, acetylases, and epimerases, with the latter being of particular interest for tailoring alginate properties. The extracellular AlgE family of epimerases, such as AlgE1-7 from Azotobacter vinelandii, have been well-characterized and show promise for the production of alginates with desired properties.
ESSAYS IN BIOCHEMISTRY
(2023)
Article
Polymer Science
Yu Shao, Bo Hou, Weiyi Li, Xiaojin Yan, Xiaoge Wang, Yuchun Xu, Qingshu Dong, Weihua Li, Jinlin He, Wen -Bin Zhang
Summary: In this work, we designed and synthesized three-component bolaform giant surfactants that can form three-phase-four-layer lamellar (LAM3) structures with sub-5 nm feature sizes. By utilizing phase separation among three mutually incompatible components, we obtained LAM3 structures with sharp interfaces and d-spacings of 12-19 nm. Moreover, the morphology of the LAM3 structures can be transformed into a hierarchical lamellar structure with extremely small Si-rich layers (approximately 2 nm in thickness) through oxygen plasma treatment. This study demonstrates the versatility of these bolaform giant surfactants in producing unconventional nanostructures with small feature sizes.
Article
Biotechnology & Applied Microbiology
Margrethe Gaardlos, Tonje Marita Bjerkan Heggeset, Anne Tondervik, David Teze, Birte Svensson, Helga Ertesvag, Havard Sletta, Finn Lillelund Aachmann
Summary: The structure and functional properties of alginates are determined by the monomer composition and molecular weight distribution, influenced by enzymes like mannuronan C-5-epimerases and alginate lyases. AIgE7 from Azotobacter vinelandii showcases dual epimerase and lyase activities, influenced by calcium and NaCl. Mutational studies on AIgE7 identified key residues, suggesting a unified catalytic mechanism for both activities. Understanding these mechanisms has implications for the enzymatic tailoring of alginate polymers in various industries.
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
(2022)
Article
Chemistry, Applied
Hyungtaek Kim, Dahee Song, Hai Ngo, Gang Jin, Chulhun Park, Jun-Bom Park, Beom-Jin Lee
Summary: This study aimed to design an alginate in situ forming gel injectable with controlled release of hydrophobic drug and clinically acceptable gelation time. By adjusting the ratio of ingredients, the gelation time was controlled effectively to release the drug without initial burst release. This injectable has potential for delivering long-acting drugs.
CARBOHYDRATE POLYMERS
(2021)
Article
Biochemistry & Molecular Biology
Margrethe Gaardlos, Anders Lervik, Sergey A. Samsonov
Summary: This study investigates the role of calcium in the structure and catalytic activity of the A-module of AvAlgE6, an epimerase enzyme in A. vinelandii. Molecular dynamics simulations reveal that calcium plays a crucial role in the hydrophobic packing and substrate binding of the enzyme. The presence of calcium increases the binding strength and affects the dissociation pathways of the substrate.
COMPUTATIONAL AND STRUCTURAL BIOTECHNOLOGY JOURNAL
(2023)
Article
Biochemistry & Molecular Biology
Akira Inoue, Takao Ojima
Summary: This study reported the functional identification of a DEHU reductase, SjRed, in the brown alga Saccharina japonica, marking the first discovery of a DEHU-reductase in alginate-producing organisms. The enzyme was found to convert DEHU to KDG and its activity was influenced by temperature, pH, and KCl concentration.
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
(2021)
Article
Pharmacology & Pharmacy
Sanung Eom, Jaeeun Lee, Yeong-Bin Baek, Hye Duck Yeom, Shinhui Lee, Chaelin Kim, Youngseo Park, Sang-Ik Park, Chang-Min Lee, Junho H. Lee
Summary: The component Schisandrin C from Schisandra interacts with the 5-HT3A receptor to potentially treat IBS by suppressing excessive neuronal serotonin signaling.
EUROPEAN JOURNAL OF PHARMACOLOGY
(2021)
Article
Biology
Shuqing Zheng, Wenjing Tao, Haowen Yang, Thomas D. Kocher, Zhijian Wang, Zuogang Peng, Li Jin, Deyong Pu, Yaoguang Zhang, Deshou Wang
Summary: Teleosts are important models for studying sex chromosomes and sex-determining genes. In this study, a high-contiguity chromosome-level genome assembly on a YY southern catfish was generated using Nanopore and Hi-C technologies. The study identified a candidate sex-determining gene in the sex-determining region and confirmed the role of amhr2y in male sex determination.
PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
(2022)
Article
Fisheries
Maqsood Ahmed Soomro, Song Li, Tushar Ramesh Pavase, Qiuming Liu, Guobin Hu
Summary: The study cloned and identified several key immune response genes from turbot, including MDA5, MAVS, TRAF3, TANK, and TBK1. These genes were rapidly upregulated in various tissues after viral challenges, suggesting their crucial role in antiviral immune response.
AQUACULTURE RESEARCH
(2021)
Article
Endocrinology & Metabolism
Keigo Murata, Yuri Ishiuchi-Sato, Taku Nedachi
Summary: Skeletal muscle is an endocrine organ and produces myokines. This study found that heat stimulation can decrease the secretion of CCL5 from skeletal muscle, both in vitro and in vivo.
Article
Endocrinology & Metabolism
Keigo Murata, Yuri Ishiuchi-Sato, Taku Nedachi
Summary: The skeletal muscle produces protein and peptide molecules called myokines, but it is unclear whether myokine secretion is regulated by heat stimulation. This study explored the effects of environmental heat stimulation on myokine secretion and found that heat stimulation decreases CCL5 secretion from skeletal muscle in vitro and in vivo.
Article
Medicine, Research & Experimental
Hui Li, Yuhang Chen, Junshi Zhang, Yongquan Lin, Zhilong Yang, Juan Tan, Wentao Qiao
Summary: This study investigated the mechanism of upregulation of c-fos mRNA translation efficiency when cellular protein synthesis is shut off. The results showed that EV71 infection led to increased levels of c-Fos protein expression in rhabdomyosarcoma cells. Further analysis revealed the role of PCBP2 and La in regulating the IRES activity of c-fos, providing a novel target for gene translation regulation.
INTERNATIONAL JOURNAL OF MOLECULAR MEDICINE
(2021)
Article
Pharmacology & Pharmacy
Keiko Kanamori, Syed M. Ahmad, Chang Sung Shin, Abdul Hamid, Kabirullah Lutfy
Summary: This study identified two oxidation products of cotinine, 5-hydroxycotinine and cotinine N-oxide, for the first time in the plasma of mice. The results highlight the importance of considering these oxidation products in studying cotinine metabolism and disposition.
DRUG METABOLISM AND DISPOSITION
(2022)
Article
Biotechnology & Applied Microbiology
Margrethe Gaardlos, Tonje Marita Bjerkan Heggeset, Anne Tondervik, David Teze, Birte Svensson, Helga Ertesvag, Havard Sletta, Finn Lillelund Aachmann
Summary: The structure and functional properties of alginates are determined by the monomer composition and molecular weight distribution, influenced by enzymes like mannuronan C-5-epimerases and alginate lyases. AIgE7 from Azotobacter vinelandii showcases dual epimerase and lyase activities, influenced by calcium and NaCl. Mutational studies on AIgE7 identified key residues, suggesting a unified catalytic mechanism for both activities. Understanding these mechanisms has implications for the enzymatic tailoring of alginate polymers in various industries.
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
(2022)
Article
Oncology
Eirini-Maria Giatagana, Aikaterini Berdiaki, Margrethe Gaardlos, Sergey A. Samsonov, George N. Tzanakakis, Dragana Nikitovic
Summary: Osteosarcoma is an aggressive bone cancer, and biglycan plays a role in promoting its growth and resistance to chemotherapy by activating the IGF-IR signaling pathway. This mechanism varies in different levels of differentiation in osteosarcoma cells.
Article
Biotechnology & Applied Microbiology
Hanne Haslene-Hox, Guro Kruge Naerdal, Yrr Morch, Gunhild Hageskal, Anne Tondervik, Anette Vikenes Turoy, Heidi Johnsen, Geir Klinkenberg, Havard Sletta
Summary: This study developed a high-throughput robotic microtiter plate-based screening assay that mimics the filamentous morphology of C. albicans. The assay demonstrated the effectiveness of nutritional drinks in promoting the growth of C. albicans and showed that amphotericin B had a reduced inhibitory effect in the presence of these drinks. This assay can facilitate efficient antifungal drug discovery and development.
JOURNAL OF APPLIED MICROBIOLOGY
(2022)
Article
Plant Sciences
Anne Tondervik, Randi Aune, Adelheid Degelmann, Michael Piontek, Helga Ertesvag, Gudmund Skjak-Braek, Havard Sletta
Summary: Alginates, linear polysaccharides produced by brown algae and bacteria, have various applications in industrial, medical, and pharmaceutical fields. This study investigates the potential of using H. polymorpha for large-scale production of alginate epimerases. The results suggest that H. polymorpha is a suitable host organism for this purpose.
FRONTIERS IN PLANT SCIENCE
(2022)
Article
Biophysics
Agnes Beenfeldt Petersen, Idd Andrea Christensen, Mette E. Ronne, Emil G. P. Stender, David Teze, Birte Svensson, Finn Lillelund Aachmann
Summary: This study reports the isotopically labeled BeKdgF from Bacteroides eggerthii from the human gut microbiota and the assignment of its H-1, C-13, and N-15 NMR chemical shifts.
BIOMOLECULAR NMR ASSIGNMENTS
(2022)
Article
Biotechnology & Applied Microbiology
Paulina S. Birgersson, Maren Oftebro, Wenche Strand, Olav A. Aarstad, Gerd Inger Saetrom, Havard Sletta, Oystein Arlov, Finn Lillelund Aachmann
Summary: Norway has a well-established seaweed industry based on extraction of alginates from wild harvested brown algae, LH. However, further expansion of wild harvest is limited, and cultivated seaweed can contribute to meeting increasing demands for high value compounds in an environmentally sustainable manner. Herein, an integrated process for retrieving alginate, fucoidan, laminarin and cellulose was established for cultivated SL and AE.
ALGAL RESEARCH-BIOMASS BIOFUELS AND BIOPRODUCTS
(2023)
Article
Biotechnology & Applied Microbiology
Katharina Nokling-Eide, Anne-Mari Langeng, Andreas Aslund, Finn Lillelund Aachmann, Havard Sletta, Oystein Arlov
Summary: Alginates, derived from brown algae, have various applications in food, technical, and pharmaceutical industries. Norway, the largest seaweed producer in Europe, mainly cultivates Alaria esculenta and Saccharina latissima. The extraction protocols for high-quality alginate from these species have been established, with optimized parameters such as pH and extraction time. The extracted alginates showed comparable purity to commercial products.
ALGAL RESEARCH-BIOMASS BIOFUELS AND BIOPRODUCTS
(2023)
Article
Multidisciplinary Sciences
Eirik G. Kommedal, Camilla F. Angeltveit, Leesa J. Klau, Ivan Ayuso-Fernandez, Bjornar Arstad, Simen G. Antonsen, Yngve Stenstrom, Dag Ekeberg, Francisco Girio, Florbela Carvalheiro, Svein J. Horn, Finn Lillelund Aachmann, Vincent G. H. Eijsink
Summary: The degradation of plant biomass is promoted by light through the generation of hydrogen peroxide, which is used by enzymes to degrade cellulose. This light-driven abiotic reaction provides opportunities for bioprocessing and offers an enzymatic explanation for the effect of visible light on biomass conversion.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Applied
Christoph Schilling, Leesa J. Klau, Finn L. Aachmann, Broder Ruehmann, Jochen Schmid, Volker Sieber
Summary: Combinatorial knock-outs of glycosyltransferases were used to identify the repeating units of two new heteroexopolysaccharides, paenan I and paenan III, produced by P. polymyxa.
CARBOHYDRATE POLYMERS
(2023)
Article
Chemistry, Applied
Francesca Scognamiglio, Michela Cok, Francesco Piazza, Eleonora Marsich, Sabrina Pacor, Olav A. Aarstad, Finn L. Aachmann, Ivan Donati
Summary: Alginate-based hydrogels with tunable mechanical properties were developed through chemical methylation of the polysaccharide backbone. Methylated alginates were used to manufacture calcium-reticulated hydrogels for cell growth in 3D. It was found that the degree of crosslinking affected the shear modulus of the hydrogels, and the mechanical properties influenced cell activity and the localization of YAP/TAZ protein complex.
CARBOHYDRATE POLYMERS
(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
Food Science & Technology
Mikkel Madsen, Sanaullah Khan, Sonja Kunstmann, Finn L. Aachmann, Richard Ipsen, Peter Westh, Cecilia Emanuelsson, Birte Svensson
Summary: This study challenges the dogma of pretreatment in whey protein modification by showing that enzymatic cross-linking of whey proteins and 13-lactoglobulin can be achieved without pretreatment. The cross-linked proteins had altered structure and showed different complexation behavior with alginate.
FOOD CHEMISTRY: MOLECULAR SCIENCES
(2022)
Article
Chemistry, Multidisciplinary
Mariana Adina Matica, Finn Lillelund Aachmann, Anne Tondervik, Havard Sletta, Vasile Ostafe
Summary: Different types of chitosan were used to prepare membranes with enhanced antibacterial properties by incorporating antimicrobial peptide Nisin. The membranes showed good physico-chemical properties and stability under enzymatic degradation, and the addition of Nisin significantly improved their antibacterial effect.
STUDIA UNIVERSITATIS BABES-BOLYAI CHEMIA
(2022)