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Introduction: Sweet sorghum juice is a typical production feedstock for natural, eco-friendly sweeteners and beverages. Clostridium tyrobutyricum is one of the widely used microorganisms in the food industry, and its principal product, bio-butyric acid is an important food additive. There are no published reports of Clostridium tyrobutyricum producing butyric acid using SSJ as the sole substrate without adding exogenous substances, which could reach a food-additive grade. This study focuses on tailoring a cost-effective, safe, and sustainable process and strategy for their production and application. Methods: This study modeled the enzymolysis of non-reducing sugars via the first/second-order kinetics and added food-grade diatomite to the hydrolysate. Qualitative and quantitative analysis were performed using high-performance liquid chromatography, gas chromatography-mass spectrometer, full-scale laser diffraction method, ultra-performance liquid chromatography-tandem mass spectrometry, the cell double-staining assay, transmission electron microscopy, and Oxford nanopore technology sequencing. Quantitative realtime polymerase chain reaction, pathway and process enrichment analysis, and homology modeling were conducted for mutant genes. Results: The treated sweet sorghum juice showed promising results, containing 70.60 g/L glucose and 63.09 g/L fructose, with a sucrose hydrolysis rate of 98.29% and a minimal sucrose loss rate of 0.87%. Furthermore, 99.62% of the colloidal particles and 82.13% of the starch particles were removed, and the concentrations of hazardous substances were effectively reduced. A food microorganism Clostridium tyrobutyricum TGL-A236 with deep utilization value was developed, which showed superior performance by converting 30.65% glucose and 37.22% fructose to 24.1364 g/L bio-butyric acid in a treated sweet sorghum juice (1:1 dilution) fermentation broth. This titer was 2.12 times higher than that of the original strain, with a butyric acid selectivity of 86.36%. Finally, the Genome atlas view, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and evolutionary genealogy of genes: Non-supervised Orthologous (eggNOG) functional annotations, three-dimensional structure and protein cavity prediction of five non-synonymous variant genes were obtained. Conclusion: This study not only includes a systematic process flow and indepth elucidation of relevant mechanisms but also provides a new strategy for green processing of food raw materials, improving food microbial performance, and ensuring the safe production of food additives. [ABSTRACT FROM AUTHOR]

Introduction: Clostridium tyrobutyricum has considerable prospect in the production of organic acids. Globally, refinery final molasses is rich in sugar and reported to have high levels of accumulation and high emission costs, recognized as an excellent substrate for C. tyrobutyricum fermentation, but there is no suitable method available at present. Methods: In this study, an acid-base treatment combined with a new green membrane treatment technology – a dynamic ion-exchange membrane -was used to pretreat refinery final molasses, so that it could be used for C. tyrobutyricum to produce butyric acid. A high-performance liquid chromatography method was established to determine the conversion of a large amount of sucrose into fermentable sugars (71.88 g/L glucose and 38.06 g/L fructose) in the treated refinery final molasses. The process of sequential filtration with 3, 1, and 0.45 µm-pore diameter dynamic ion-exchange membranes could remove impurities, pigments, and harmful substances from the refinery final molasses, and retain the fermentable sugar. Results and discussion: This means that refinery final molasses from the sugar industry could be utilized as a high-value by-product and used for the growth of C. tyrobutyricum, with industrial feasibility and economic competitiveness. Using the treated refinery final molasses as a carbon source, C. tyrobutyricum was screened by the method of adaptive evolution. The strain with butyric acid yielded 52.54 g/L, and the yield of the six carbon sugar was increased from 0.240 to 0.478 g/g. The results showed that combination of C. tyrobutyricum and ionic membrane technology broke through the bottleneck of its utilization of refinery final molasses. This study provided an innovative idea for the C. tyrobutyricum fermentation to produce butyric acid. [ABSTRACT FROM AUTHOR]

A growing consensus worldwide has indicated the need to protect the ecological environment and achieve sustainable development. Ensuring ecological protection and high-quality development of the Yellow River basin have become China's major national strategy. We reviewed extant literature, summarised government reports and guidance documents on the Yellow River basin, and proposed introducing a strong sustainable development theory into the study of total factor productivity (TFP). The spatial–temporal evolution and influencing factors of urban ecological TFP in the Yellow River basin are of great practical significance. We proposed a new ecological TFP indicator: the modified input-oriented Luenberger productivity indicator (MIL). Using panel data from 78 cities in the Yellow River basin during 2003–2019, we measured the urban ecological TFP. We adopted the geographic information system tool and kernel density estimation to analyse the temporal and spatial evolution of the indicator, as well as its spatial effects and influencing factors, using the global Moran's I index and dynamic spatial Durbin model (SDM). Our results show that, during the sample period, our indicator increased in cities in the region with an average annual growth rate of 0.627%, driven by technological progress. The average annual growth rate in urban areas showed a decreasing distribution of ‘downstream-midstream-upstream’. Fiscal decentralisation (FD), industrial structure (IND), financial development (FIN), urbanisation level (URB) and research and development (RD) investment improved growth rates in this and the adjacent regions through direct and indirect effects. However, environmental regulation (ER), opening level (OPEN) of cities and population density (POP) were obstacles to TFP growth. [ABSTRACT FROM AUTHOR]

N-methyl-D-aspartate receptors (NMDARs) are glutamate-gated cation channels that mediate excitatory neurotransmission and are critical for synaptic development and plasticity in the mammalian central nervous system (CNS). Functional NMDARs typically form via the heterotetrameric assembly of GluN1 and GluN2 subunits. Variants within GRIN genes are implicated in various neurodevelopmental and neuropsychiatric disorders. Due to the significance of NMDAR subunit composition for regional and developmental signaling at synapses, properly folded receptors must reach the plasma membrane for their function. This review focuses on the protein quality control of NMDARs. Specifically, we review the quality control mechanisms that ensure receptors are correctly folded and assembled within the endoplasmic reticulum (ER) and trafficked to the plasma membrane. Further, we discuss disease-associated variants that have shown disrupted NMDAR surface expression and function. Finally, we discuss potential targeted pharmacological and therapeutic approaches to ameliorate disease phenotypes by enhancing the expression and surface trafficking of subunits harboring disease-associated variants, thereby increasing their incorporation into functional receptors. [ABSTRACT FROM AUTHOR]

Coenzyme A (CoA) mediates thiol-based acyl-group transfer (acetylation and palmitoylation). However, a role for CoA in the thiol-based transfer of NO groups (S-nitrosylation) has not been considered. Here we describe protein S-nitrosylation in yeast (heretofore unknown) that is mediated by S-nitroso-CoA (SNO-CoA). We identify a specific SNO-CoA reductase encoded by the alcohol dehydrogenase 6 (ADH6) gene and show that deletion of ADH6 increases cellular S-nitrosylation and alters CoA metabolism. Further, we report that Adh6, acting as a selective SNO-CoA reductase, protects acetoacetyl-CoA thiolase from inhibitory S-nitrosylation and thereby affects sterol biosynthesis. Thus, Adh6-regulated, SNO-CoA-mediated protein S-nitrosylation provides a regulatory mechanism paralleling protein acetylation. We also find that SNO-CoA reductases are present from bacteria to mammals, and we identify aldo-keto reductase 1A1 as the mammalian functional analog of Adh6. Our studies reveal a novel functional class of enzymes that regulate protein S-nitrosylation from yeast to mammals and suggest that SNO-CoA-mediated S-nitrosylation may subserve metabolic regulation. [ABSTRACT FROM AUTHOR]

This paper indicated that inactivated Bordetella pertussis (iBp) can enhance the lung airway hyperreactivity of the rats sensitized and challenged with OVA. The mechanisms were involved in the upregulation of cAMP-PDE activity and PDE4A, PDE4D, and PDE3 gene expression in the lungs. But only PDE4 activity was different between the OVA and OVA+iBp groups, and PDE4D expression was significantly increased in iBp rats alone. So, our data suggested that cosensitization with OVA and iBp affects lung airway reactivity by modulating the lung cAMP-PDE activity and PDE4D gene expression. [ABSTRACT FROM AUTHOR]

The thermal stability of sheepskin collagen cross-linked with chrome sulfate and mimosa (MI)–oxazolidine (OZ), respectively, had been researched in this experiment. All samples’ shrinkage temperatures ( Ts) are determined by a special Ts-testing-apparatus and denaturation temperatures ( Td) are determined by the differential scanning calorimetry. The relations between the modified collagens containing moisture and their hydrothermal stability, Ts or Td, were studied. The results show that the cross linking agents can enhance the thermal stability of modified collagen whose Ts are 109.8 and 110.6 °C for collagen treated with chrome and MI–OZ, respectively. When the samples contain 25–71.9% moisture for chrome leather and 20–71.1% for leather treated with MI–OZ, the hydrothermal stability will decrease with the increase of moisture. It was found that the difference between Ts and Td of collagen modified by chrome is more obvious than that of collagen modified with MI–OZ. And when the moisture of chrome leather exceeds 55%, Td cannot express thermal stability of modified collagen as a substitute for Ts, and the moisture is 40% for leather tanned with MI–OZ. [ABSTRACT FROM AUTHOR]

The thermal decomposition process of the complex [Cu(NBOCTB)][Cu(NO3)4] H2O has been studied by TG and DTG technique, and possible intermediates of the thermal decomposition have also been conjectured from the TG and DTG curves. The results suggest that the decomposition of the complex involves five steps: The non-isothermal kinetics of steps 1, 2 and 3 have been studied by means of the Achar and Coats-Redfern method based on TG and DTG curves. Step 1 is a ‘Coring and Growth’ mechanism ( n= 1), its kinetic equation may be expressed as: dα/d t=Ae−E/RT(1−α). Steps 2 and 3 are both ‘two order chemical reaction’ mechanisms, their kinetic equations can be expressed as: dα/d t=Ae−E/RT(1−α)2. [ABSTRACT FROM AUTHOR]