Cellulose is the most abundant renewable carbon resource on earth and is an indispensable raw material for the wood, paper, and textile industries. A model system to study the mechanism of cellulose biogenesis is the bacterium Acetobacter xylinum which produces pure cellulose as an extracellular product. It was from this organism that in vitro preparations which possessed high levels of cellulose synthase activity were first obtained in both membranous and soluble forms. We recently demonstrated that this activity is subject to a complex multi-component regulatory system, in which the synthase is directly affected by an unusual cyclic nucleotide activator enzymatically formed from GTP, and indirectly by a Ca (2+) -sensitive phosphodiesterase which degrades the activator. The cellulose synthase activator (CSA) has now been identified as bis-(3' 5')-cyclic diguanylic acid (5'G3'p5'G3'p) on the basis of mass spectroscopic data, nuclear magnetic resonance analysis and comparison with chemically synthesized material. We also report here on intermediary steps in the synthesis and degradation of this novel circular dinucleotide, which have been integrated into a model for the regulation of cellulose synthesis.
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Int J Biol Macromol
January 2025
School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland. Electronic address:
Lignocellulosic biomass represents one of the most abundant renewable biological resources on earth. Despite its current underutilization as a source of high-value chemicals, it has promising applications in biomedical and other fields. Presently, lignocellulose is predominantly transformed into high-value-added products, e.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China. Electronic address:
The limited transport of oxygen at the solid-liquid interface and the poor charge separation efficiency of single catalyst significantly impedes the generation of reactive oxygen species (ROS), thereby weakening the application potential of photocatalytic technology in water pollution control. Herein, a hollow porous photocatalytic aerogel sphere (calcium alginate/cellulose nanofibers (CA/CNF)) loaded BiOBr/TiC, combining a favourable mass transfer structure with effective catalytic centers was firstly presented. The floatability and hollow pore structure facilitated rapid O transfer via a triphase interface, thereby promoting the generation of ROS.
View Article and Find Full Text PDFPlant Cell Rep
January 2025
State Key Laboratory of Crop Genetics and Germplasm Enhancement, Saya Institute of Nanjing Agricultural University, Nanjing Agricultural University, Nanjing, 211800, China.
This study indicated that the CCHC-type zinc finger protein PbrZFP719 involves into self-incompatibility by affecting the levels of reactive oxygen species and cellulose content at the tips of pollen tubes. S-RNase-based self-incompatibility (SI) facilitates cross-pollination and prevents self-pollination, which in turn increases the costs associated with artificial pollination in fruit crops. Self S-RNase exerts its inhibitory effects on pollen tube growth by altering cell structures and components, including reactive oxygen species (ROS) level and cellulose content.
View Article and Find Full Text PDFSci Bull (Beijing)
January 2025
Hubei Biomass-Resource Chemistry and Environmental Biotechnology Key Laboratory, Hubei Provincial Engineering Research Center of Emerging Functional Coating Materials, School of Resource and Environmental Sciences, Wuhan University, Wuhan 430079, China. Electronic address:
The discontinuous fiber reinforced hydrogels are easy to fail due to the fracture of the fiber matrix during load-bearing. Here, we propose a novel strategy based on the synergistic reinforcement of interconnected natural fiber networks at multiple scales to fabricate hydrogels with extraordinary mechanical properties. Specifically, the P(AA-AM)/Cel (P(AA-AM), poly(acrylic acid-acrylamide); Cel, cellulose) hydrogel is synthesized by copolymerizing AA and AM on a substrate of paper with an interconnected hollow cellulose microfiber network.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University; Yangling, Shaanxi 712100, China. Electronic address:
Biofilms are complex adhesive structures that establish chronic infection and allow robust protection from external stressors such as antibiotics. Cellulose as one of the compositions of bacteria biofilm which protect bacteria from stress, host immune responses and resistance to antibiotics. Bacterial stress responses are regulated via guanosine pentaphosphate and tetraphosphate (p)ppGpp.
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