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SUMMARYThe chemical reaction networks (CRNs), which led to the transition on early Earth from geochemistry to biochemistry remain unknown. We show that under mild hydrothermal circumstances, a thermodynamic chemical reaction network including sulfite/sulfate coupled with anaerobic ammonium oxidation (Sammox), might have driven prebiotic peptides synthesis. Peptides comprise 14 proteinogenic amino acids, endowed Sammox-driven CRNs with autocatalysis. The peptides exhibit both forward and reverse catalysis, with the opposite catalytic impact in sulfite- and sulfate-fueled Sammox-driven CRNs, respectively, at both a variable temperature range and a fixed temperature, resulting in seesaw-like catalytic properties. The ratio of sulfite to sulfate switches the catalytic orientation of peptides, resulting in Sammox-driven CRNs that has both anabolic and catabolic reactions at all times. Furthermore, peptides produced from sulfite-fueled Sammox-driven CRNs could catalyze both sulfite-fueled Sammox and Anammox (nitrite reduction coupled with anaerobic ammonium oxidation) reactions. We propose that Sammox-driven CRNs were critical in the creation of life and that Anammox microorganisms that have both Sammox functions are direct descendants of Sammox-driven CRNs.

The level of autophagy in CD11c

We report the draft genome sequence of Thermomonas sp. strain XSG, isolated from a marine sediment. The genome is 3,047,478 bp long with a GC content of 68.5%., We report the draft genome sequence of Thermomonas sp. strain XSG, isolated from a marine sediment. The genome is 3,047,478 bp long with a GC content of 68.5%. Strain XSG was found to be closely related to strain NBRC 101115 of Thermomonas koreensis.

The antibiotic-resistant bacteria (ARB) and antibiotic-resistant genes (ARGs) in Wastewater treatment plants (WWTPs) have attracted increasing attention. In this study, the abundance of ARB and resistance genes tet32 and defA1 were investigated using high-throughput sequencing and high-throughput qPCR in water samples collected from the inlet of the biological treatment pool and outlet of Beilun Yandong WWTP in Ningbo, China. The result shows there was a high level of ARGs in the water of both the inlets and outlets in 2017 and 2018, whereas no ARGs were detected after adding a new baffled bioreactor (BBR) water treatment process in 2019. The BBR process uses Bacillus subtilis, B. thuringiensis, B. megaterium, B. licheniformis and B. amyloliquefaciens to effectively eliminate the ARGs in wastewater. Notably, this process did not significantly change the bacterial community structure of outlet water samples. The findings demonstrate an effective new method for removing ARGs from sewage.

The genus Bradyrhizobium is considered to be widespread and abundant group of symbiotic bacteria in many plant-soil ecosystems. However, the ecological versatility of this phylogenetic group remains highly understudied in man-made ecosystems, mainly due to the lack of pure cultures and genomic data. To further expand our understanding of this genus for human health, we analyzed the high quality draft genome of Bradyrhizobium strain BL, isolated from a municipal wastewater treatment plant in Ningbo, China. The Bradyrhizobium sp. BL draft genome has a total size of 7,718,431 bp with an overall G + C content of 46.43%. From a total of 7236 predicted sequences, 7176 and 60 are protein and RNA coding sequences, respectively. Moreover, 63.51% of the predicted genes were assigned into to Clusters of Orthologous Groups (COG) functional categories. The Bradyrhizobium sp. BL genome contains various defense mechanisms against antibiotics that up to predicted 60 antibiotic resistance coding genes. The Bradyrhizobium sp. BL genome contains 237 termed virulence factors coding genes which show its potential pathogenicity. This study provides important insights into the genomic diversity of the genus Bradyrhizobium and provides a foundation for future comparative genomic studies that will generate a better understanding of the antibiotic resistance process.

In an attempt to develop potent and selective antitumor agents, a series of 6- and 2-(1-substituted-thio-4-methylpent-3-enyl)-5,8-dimethoxynaphthalene-1,4-diones were designed and synthesized. The cytotoxicities of these compounds were evaluated in vitro against BEL-7402, HT-29 and SPC-A1 cell lines. The pharmacological results showed that most of the prepared compounds displayed the excellent selective cytotoxicity toward HT-29 cells. From the structure-activity relationships we may conclude that the introduction of a thioether functional group at the 1'-position in the side chain of shikonin is associated with an increase in cytotoxicity.

Sixteen novel 6- and 2-(1-acylsulfanylalkyl)-5,8-dimethoxy-1,4-naphthoquinones were designed and synthesized. Their cytotoxicities were evaluated in vitro against BEL-7402, HT-29 and SPC-A1 cell lines. The pharmacological results showed that most of the prepared compounds displayed the excellent selectivity for HT-29 cell line. Compound 16b exhibited the most potent antitumor activity among the tested compounds.

The calcium-sensing receptor (CaSR), a G protein coupled receptor, is involved in a number of physiological and pathological processes. Embryonic stem cells (ESCs) have a potential role to differentiate into all types of cells. Whether CaSR is functionally expressed in ESCs is unclear. In this study, the expression and distribution of CaSR in 129 mouse ES-D3 cell lines were detected by Western blotting and immunofluorescence; and the intracellular calcium concentration ([Ca(2+)]i) was measured using Laser Confocal Scanning Microscopy. Mouse embryonic stem cells (mESCs) were cultured to embryoid bodies (EBs) and the differentiation of EBs into cardiomyocytes was induced by icariin (ICA). The cardiac specific proteins, a-Actinin and cardiac troponin-I (cTnI), were analyzed by immunofluorescence, and the differentiation rate was analyzed by flow cytometry. The expression of cardiac-specific transcription factors, Nkx2.5 and GATA-4, was detected by Western blotting. We found that the CaSR protein exists in both mESCs and mESC-derived cardiomyocytes (mESC-CMs). Increasing extracellular calcium or neomycin (an agonist of CaSR) increased [Ca(2+)]i and the differentiation rate. These effects were abolished by inhibition of CaSR, phospholipase C, IP3 receptor and Ca(2+) ATPase, or by depletion of the sarcoplasmic reticulum Ca(2+) store, respectively. Activation of CaSR up-regulated protein expression of Nkx2.5 and GATA4 in EBs at an early stage of ICA-induced differentiation. In conclusion, CaSR is functionally expressed in mESCs, and activation of CaSR is involved in the differentiation of mESCs into cardiomyocytes by facilitating the expression of NKx2.5 and GATA-4.

In an attempt to develop potent and selective antitumor agents, a series of 6- and 2-(1-substituted-thio-4-methylpent-3-enyl)-5,8-dimethoxynaphthalene-1,4-diones were designed and synthesized. The cytotoxicities of these compounds were evaluated in vitro against BEL-7402, HT-29 and SPC-A1 cell lines. The pharmacological results showed that most of the prepared compounds displayed the excellent selective cytotoxicity toward HT-29 cells. From the structure-activity relationships we may conclude that the introduction of a thioether functional group at the 1'-position in the side chain of shikonin is associated with an increase in cytotoxicity.