Salecan, a soluble β-1,3-D-glucan produced by a salt-tolerant strain Agrobacterium sp. ZX09, has been the subject of considerable interest in recent years because of its multiple bioactivities and unusual rheological properties in solution. In this study, both succinyl and pyruvyl substituent groups on salecan were identified by an enzymatic hydrolysis following nuclear magnetic resonance (NMR), HPLC, and MS analysis. The putative succinyltransferase gene (sleA) and pyruvyltransferase gene (sleV) were determined and cloned. Disruption of the sleA gene resulted in the absence of succinyl substituent groups on salecan. This defect could be complemented by expressing the sleA cloned in a plasmid. Thus, the sleA and sleV genes located in a 19.6-kb gene cluster may be involved in salecan biosynthesis. Despite the lack of succinyl substituents, the molecular mass of salecan generated by the sleA mutant did not substantially differ from that generated by the wild-type strain. Loss of succinyl substituents on salecan changed its rheological characteristics, especially a decrease in intrinsic viscosity.
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http://dx.doi.org/10.1007/s00253-016-7814-z | DOI Listing |
ChemMedChem
January 2025
Universita degli Studi di Catania, Department of Drug Sciences, Viale A. Doria, 6, 95100, Catania, ITALY.
This study presents a series of tetrahydropyrrolo[3,4-c]pyrazole-based compounds designed as sigma-1 receptor (S1R) ligands, focusing on optimizing affinity and reducing off-target effects. We synthesized various derivatives from commercially available precursors and, through radioligand binding assays, assessed their binding affinity for S1R and sigma-2 receptor (S2R). Compound 19 (AD417), containing a benzyl group and an amide substituent, demonstrated notable S1R affinity (Ki = 75 nM) with 6-fold selectivity over S2R.
View Article and Find Full Text PDFChemistry
January 2025
Aristotle University of Thessaloniki: Aristoteleio Panepistemio Thessalonikes, Department of Chemistry, 54124, Thessaloniki, GREECE.
Cyclopropane derivatives serve as important building blocks in organic synthesis, due to their three-membered stretched ring. Nitro-substituted cyclopropanes (NCPs) represent a special class of donor-acceptor cyclopropanes (DACs) that contain a strong electron-withdrawing nitro group as substituent on the cyclopropyl moiety. Due to the versatile nature of the nitro group, which can be converted into other functional azo groups or heterocyclic scaffolds, NCPs are considered important building blocks in the design of complex organic compounds.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Department of Applied Chemistry, Xi'an Key Laboratory of Sustainable Energy Materials Chemistry, National Innovation Platform (Center) for Industry-Education Integration of Energy Storage Technology, Engineering Research Center of Energy Storage Materials and Devices of Ministry of Education, School of Chemistry, Xi'an Jiaotong University, Xi'an, 710049, P. R. China.
Achieving high-performance dielectric materials remains a significant challenge due to the inherent trade-offs between high energy storage density and low energy loss. A central difficulty lies in identifying a suitable dipolar unit that can enhance the polarity and dielectric constant of the material while effectively suppressing the high energy losses associated with polarization relaxation, charge injection, and conduction. To address this, a novel strategy is proposed that introduces electron-donating and electron-withdrawing substituents on the benzene ring of polystyrene-based polymers, creating bulky dipole groups that are resistant to reorientation under an electric field.
View Article and Find Full Text PDFFuture Med Chem
January 2025
Department of Pharmaceutical Chemistry, ISF College of Pharmacy, Moga, India.
The study of chalcone-1,2,3-triazole hybrids for anticancer activity is quite a recent area of focus, primarily because of the increasing demand for developing new drugs to treat cancer. The chalcones and 1,2,3-triazole rings in hybrid compounds has recently emerged as a promising strategy for developing novel anticancer agents. The 1,2,3-triazole ring, known for its stability and hydrogen bonding capabilities, enhances the target binding affinity of these hybrids.
View Article and Find Full Text PDFBiochem Biophys Rep
March 2025
Department of Chemistry, University of Nebraska at Kearney, USA.
Human citrate synthase (hCS) was kinetically characterized through full progress curve kinetic modelling using kinetic simulation, global fitting of the direct AcCoA to CoA transition, and a coupled thiol probe reaction to better determine the kinetics with low substrate concentration. Our analysis provides one of the most rigorous kinetic analyses of any citrate synthase ruling out the need to invoke complex cooperative mechanisms to explain progress curve data. Furthermore, we collected and modeled stopped-flow pH-dependent kinetic data with CoA and popular thiol probes such as Ellman's reagent (DTNB) and 4,4'-Dithiodipyridine (DPS), providing the opportunity for detailed kinetic simulations using these thiol probes with CoA producing enzymes.
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