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Tuberculosis, caused by mycobacteria, continues to pose a substantial public health threat. Mycobacteria typically use cholesterol from the membranes of host macrophages as a carbon and energy source. Most genes that control cholesterol degradation are regulated by KstR, which is highly conserved in Mycobacterium tuberculosis and Mycobacterium smegmatis. Through bioinformatic analysis, we found a typical global nitrogen regulator (GlnR)‐binding motif (CCGAC‐AACAGT‐GACAC) in the promoter region of kstR of M. smegmatis, and we determined its binding activity in vitro using electrophoretic mobility shift assays. Using RT‐qPCR, we found that nine genes involved in side‐chain or sterol‐ring oxidation were upregulated in a ΔglnR M. smegmatis strain compared to the WT strain and glnR‐complemented strains under nitrogen limitation. ATP assays in macrophages revealed that coordinated GlnR–KstR regulation significantly reduced the viability of M. smegmatis in macrophages. Thus, we found that various genes involved in cholesterol catabolism are regulated by GlnR via KstR in response to environmental nitrogen, and that they further affect the invasive ability of M. smegmatis. These findings revealed a novel regulatory mechanism of cholesterol catabolism, which may be useful in the development of new strategies for controlling tuberculosis. [ABSTRACT FROM AUTHOR]

Oral lichen planus (OLP) is a chronic inflammatory disease, has prolonged courses, repeated attacks and resistance to treatment. The traditional narrow spectrum UVB treatment has an established efficacy on skin lichen planus, and high safety. However, most of ultraviolet phototherapy devices have a huge volume, thereby cannot be used in the treatment of OLP. Lymphocytic infiltration is evident in the lesions of lichen planus, and the direct irradiation of 308-nm excimer laser can induce apoptosis of the T lymphocytes in skin lesions, thereby has a unique therapeutic effect on the diseases involving T lymphocytes. This study aims to investigate the efficacy of 308-nm excimer laser in the treatment of OLP. A total of six OLP patients were enrolled into this study, and further pathological diagnosis was conducted, then 308-nm excimer laser was used in the treatment. The efficacy of 308-nm excimer laser in the treatment of OLP was satisfactory. The clinical symptoms of five patients were significantly improved. In two patients, the erosion surface based on congestion and the surrounding white spots completely disappeared, and clinical recovery was achieved. Three patients achieved partial remission, that is, the erosion surface healed, congestion and white spot area shrunk by more than 1/2 of the primary skin lesions. In the remaining one patient, the erosion surface had not completely healed after treatment, and congestion and white spot area shrunk by less than 1/2 of the primary skin lesions. Only one patients had developed mild pain during the treatment, and this symptom alleviated by itself. The 308-nm excimer laser therapy can serve as a safe and effective treatment for OLP. [ABSTRACT FROM AUTHOR]

Various polysubstituted α-pyrone derivatives have been directly synthesized via a of Michael additional reaction following a cyclized process catalyzed by the Lewis acid of Zn(OAc)2. This protocol provides a new convenient and step-economical route to construct heterocycles. Fourteen examples are obtained from easily available materials with moderate to good yields. [ABSTRACT FROM AUTHOR]

The addition/oxidative cyclization of alkynoates with 1,3-dicarbonyl compounds in the presence of Ag(I) leads to polysubstituted furans. The reaction corresponds to the construction of a furan fragment, which also provides a new way to form the C-O bond. [ABSTRACT FROM AUTHOR]

Abstract: One hundred and twenty-one Salmonella isolates were obtained from food, feed, and live chicken samples derived from 13 countries or regions. In this study, their subtypes were evaluated by serotyping and multilocus sequence typing (MLST), and their genetic profiles were also characterized. It was demonstrated by serotyping on these isolates that 36 various serovars were obtained in this study, of which three serotypes S. Babelsberg, S. Fresno, and S. II were first found in mainland China. Based on Simpson’s index of diversity, the serotyping method had a 0.943 discriminatory power. Meanwhile, there were a total of 42 unique sequence types (STs) characterized by MLST, and the discriminatory power of MLST (D = 0.947) was close to that of the serotyping method. In MLST, hisD revealed the highest levels of nucleotide diversity. In addition, ST-92 was the most common ST represented by 16 Salmonella isolates, followed by ST-367 which was represented by 14 isolates. Seven new alleles were identified, which were associated with other alleles and resulted in the assignment of nine new STs. It was concluded from the results that MLST was generally associated with serotype, but not associated with the epidemiological source of the samples, and antimicrobial resistance patterns. [Copyright &y& Elsevier]

Abstract: Polysubstituted 1,2,3,4-tetrahydropyridines were synthesized through hydroalkylation of electron-deficient alkynes, followed by double Mannich addition reactions, which is a practical protocol with atom efficiency and good substrate scope. [Copyright &y& Elsevier]

Abstract: Polysubstituted 2H-pyran-2-ones and 5,6-dihydro-2H-pyran-2-ones were synthesized via the MCRs initiated by the hydroalkylation of alkynoates with activated methylenes. Under the optimized reaction conditions, the desired products were obtained in 47–88% isolated yields. The experimental results showed that the groups on activated methylenes act important roles in the nucleophilic attack fashion. [Copyright &y& Elsevier]

Abstract: Particle swarm optimization (PSO) is an evolutionary algorithm used extensively. This paper presented a new particle swarm optimizer based on evolutionary game (EGPSO). We map particles’ finding optimal solution in PSO algorithm to players’ pursuing maximum utility by choosing strategies in evolutionary games, using replicator dynamics to model the behavior of particles. And in order to overcome premature convergence a multi-start technique was introduced. Experimental results show that EGPSO can overcome premature convergence and has great performance of convergence property over traditional PSO. [Copyright &y& Elsevier]

[Display omitted] • A cell factory of dencichine was built by remodeling metabolism of C. glutamicum. • L-DAP was first-ever biosynthesized in C. glutamicum with 628 mg/L production. • The oxalyl-CoA synthesis pathway was established for the first time in C. glutamicum. • By optimizing metabolic pathways, the yield of dencichine was 31.75 mg/L (48 h). Dencichine, a sought-after compound in the medical industry, requires a more efficient and sustainable production method than the current plant extraction process. This study successfully remodeled the metabolic pathway of Corynebacterium glutamicum to produce dencichine from the precursors of L-2,3-diaminopropionate (L-DAP) and oxalyl-coenzyme A. Firstly, a synthetic pathway for L-DAP was established by introducing exogenous enzymes ZmaU/ZmaV. This resulted in a production of 628 mg/L by overexpressing key genes and reducing the endogenous competitive pathway. Secondly, an oxalyl-CoA synthetic pathway was created through the enzymatic conversion of glyoxylate by introducing heterologous enzymes. Finally, with the integration of the exogenous enzyme BAHD, de novo synthesis of dencichine in C. glutamicum was achieved, and production reached 31.75 mg/L within 48-hour fermentation. This achievement represents the first successful biosynthesis of dencichine in C. glutamicum , offering a promising approach for natural product through microbial fermentation. [ABSTRACT FROM AUTHOR]

Saccharopolyspora erythraea produces a large number of secondary metabolites with biological activities, including erythromycin. Elucidation of the mechanisms through which the production of these secondary metabolites is regulated may help to identify new strategies for improved biosynthesis of erythromycin. In this paper, we describe the systematic prediction and analysis of small non-coding RNAs (sRNAs) in S. erythraea, with the aim to elucidate sRNA-mediated regulation of secondary metabolite biosynthesis. In silico and deep-sequencing technologies were applied to predict sRNAs in S. erythraea. Six hundred and forty-seven potential sRNA loci were identified, of which 382 cis-encoded antisense RNA are complementary to protein-coding regions and 265 predicted transcripts are located in intergenic regions. Six candidate sRNAs (sernc292, sernc293, sernc350, sernc351, sernc361, and sernc389) belong to four gene clusters (tpc3, pke, pks6, and nrps5) that are involved in secondary metabolite biosynthesis. Deep-sequencing data showed that the expression of all sRNAs in the strain HL3168 E3 (E3) was higher than that in NRRL23338 (M), except for sernc292 and sernc361 expression. The relative expression of six sRNAs in strain M and E3 were validated by qRT-PCR at three different time points (24, 48, and 72 h). The results showed that, at each time point, the transcription levels of sernc293, sernc350, sernc351, and sernc389 were higher in E3 than in M, with the largest difference observed at 72 h, whereas no signals for sernc292 and sernc361 were detected. sernc293, sernc350, sernc351, and sernc389 probably regulate iron transport, terpene metabolism, geosmin synthesis, and polyketide biosynthesis, respectively. The major significance of this study is the successful prediction and identification of sRNAs in genomic regions close to the secondary metabolism-related genes in S. erythraea. A better understanding of the sRNA-target interaction would help to elucidate the complete range of functions of sRNAs in S. erythraea, including sRNA-mediated regulation of erythromycin biosynthesis. [ABSTRACT FROM AUTHOR]

The title synthesis provides a new way to form C-O bond. [ABSTRACT FROM AUTHOR]

The di-2-ethylhexyl phthalate (DEHP) degrading strain LMB-7 was isolated from electronic waste soil. According to its biophysical/biochemical characteristics and 16S rRNA gene analysis, the strain was identified as Nocardia asteroides. Optimal pH and temperature for DEHP degradation were 8.0 and 30 °C, respectively, and DEHP removal reached 97.11% after cultivation for 24 h at an initial concentration of 400 mg/L. As degradation intermediates, di-butyl phthalates, mono-2-ethylhexyl phthalate and 2-ethylhexanol could be identified, and it could be confirmed that DEHP was completely degraded by strain LMB-7. To our knowledge, this is a new report of DEHP degradation by a strain of Nocardia asteroides, at rates higher than those reported to date. This finding provides a new way for DEHP elimination from environment. [ABSTRACT FROM AUTHOR]

The article presents Low-dose lipopolysaccharide protects nerve cells against spinal cord injury via regulating the PI3K–AKT–Nrf2 signaling pathway. Topics discussed include this study explored the molecular mechanism behind the protective effects from low-dose lipopolysaccharide (LPS) on an in-vitro model of spinal cord injury (SCI); and PC12 cells were treated with different concentrations of LPS and the cell counting kit-8 assay was used to measure the toxicity of LPS to the cells.

The irrigation infrastructures are public goods, farmers will adopt free-riding strategy in the management and maintenance because of the individual rationality, and so there are only few people engage in the activity. The paper first established the normal model of farmers engaged in the activity, then designed a new manage model by appropriate incentives and organization forms. Farmers not only individual rationality but also can change them strategies by study, so the paper discussed the cooperation and strategy change of the farmers by evolutionary game based of Q-learning. At last, the simulation illustrated that the new model not only improved the income of the upstream and downstream farmers, but also can increase the degree of cooperation in the game. [ABSTRACT FROM AUTHOR]

Four new metal complexes {[Cu(api)2(H2O)] ·(ClO4)2 ·CH3CN} n ( 1), [Cu(api)2(ClO4)2] n ( 2), [Cd(api)2(SCN)2] n ( 3) and [Ni(api)2(SCN)2] n ( 4) (api = 1-(3-Aminopropyl)-imidazole) were synthesized by reactions of api and different metal salts under different conditions. Interestingly, complexes 1- 3 exhibit various one dimensional (1D) double chain structures, while complex 4 shows a 2D layer structure. The results indicate that metal ions, anions, solvents, and the synthesis methods, have great influence on the formation and structure of the complexes. [ABSTRACT FROM AUTHOR]

Various substituted N-aryl carbamoyl methyl diacetates have been synthesized from N-aryl-3-oxobutanamides via a diacetoxylation mediated by the combination of iodobenzene diacetate (PIDA)/Zn(OAc)2. This provides a new convenient method to form C-O bonds and cleave C-C bonds. Ten examples were obtained from easily available materials in good to excellent yields. [ABSTRACT FROM AUTHOR]

A mechanistic proposal for this novel transformation involving both C-O bond formation and C-C bond cleavage is given. [ABSTRACT FROM AUTHOR]