Construction of Sly-miR393 Over-Expression Vector and Verification of Its Target Genes in Tomato

To understand the function of Sly-miR393 in tomato, the precursor sequences and potential target genes of Sly-miR393 were identificated from tomato genome database by computational homology search method. The Sly-miR393 gene was amplified from the genomic DNA by PCR and cloned into plant expression vector pLP35s-100. Sly-miR393 guided-cleavage to putative target  transcripts was validated u sing 5RACE RT-PCR. In this study, our results indicated that the precursor sequence of Sly-miR393 contains the complete hairpin  structure. TIR1/AFB auxin receptor genes contain recognition sites with high complementarities to Sly-miR393 sequence. In tomato, Sly-miR393 directs the cleavage of SlTIR1，SlTIR1-like1 and SlAFB mRNA, then auxin receptor homologous was validated to be as target of Sly-miR393. The pLP35s-pre-SlymiR393 vector containing Sly-miR393 gene was successfully constructed, which would provide significant evidence for further study of Sly-miR393 function in auxin signaling pathway in tomato

Plant Microbiome and Mycorrhizal Fungi

In this paper, the research results on the synergy between mycorrhizal fungi and plant microorganisms in China and abroad were summarized. The purpose of this paper was to elaborate the effects of the synergy mechanism between mycorrhizal fungi and plant microorganisms on crop growth and stress resistance, soil physical and chemical properties, and soil microbial diversity and to analyze the contribution of the interaction between mycorrhizal fungi and plant microorganisms in agriculture and forestry, so as to provide theoretical basis for the further preparation of composite microbial agents, the healthy and green improvement of crop yield, and the ecological restoration of forestry stress resistance. The main directions of future research in this field were also analyzed

Cyclic Behavior and Stress–Strain Model of Nano-SiO₂-Modified Recycled Aggregate Concrete

Recycled aggregate concrete (RAC) possesses different mechanical properties than ordinary concrete because of inherent faults in recycled aggregates (RAs), such as the old interfacial transition zone (ITZ). However, the application of nano-SiO2 presents an effective methodology to enhance the quality of RA. In this study, nano-SiO2-modified recycled aggregate (SRA) was used to replace natural aggregate (NA), and the stress–strain relationships and cyclic behavior of nano-SiO2-modified recycled aggregate concrete (SRAC) with different SRA replacement rates were investigated. After evaluating the skeleton curve of SRAC specimens, the existing constitutive models were compared. Additionally, the study also proposed a stress–strain model designed to predict the mechanical behavior of concrete in relation to the SRA replacement rate. The results show that compared with RAC, the axial compressive strength of SRAC specimens showed increases of 40.27%, 29.21%, 26.55%, 16.37%, and 8.41% at specific SRA replacement rates of 0%, 30%, 50%, 70%, and 100%, respectively. Moreover, the study found that the Guo model’s calculated results can accurately predict the skeleton curves of SRAC specimens

Construction of a myoglobin scaffold-based biocatalyst for the biodegradation of sulfadiazine and sulfathiazole

Sulfonamide antibiotics, a family of broad-spectrum antibiotic drugs, are increasingly used in aquaculture and are frequently detected in aquatic environments. This poses a potential threat to organisms and may cause the evolution of antimicrobial resistance. Therefore, it is important to develop an environmentally friendly and efficient biocatalyst to degrade sulfonamides (SAs) such as sulfadiazine (SD) and sulfathiazole (ST). Here, we realized the direct and efficient degradation of SD and ST using a hydrogen peroxide-dependent artificial catalytic system based on myoglobin (Mb). The arrangements of amino acids at positions 29, 43, 64, and 68 were found to influence catalytic activity. An L29H/H64D/V68I myoglobin mutant showed the best catalytic efficiency (i.e., kcat/Km = 720.42 M-1 s-1) against SD. Next, mutant H64D/V68I showed the best degradation rate against SD (i.e., 91.45 +/- 0.16%). Moreover, L29H/H64D/V68I Mb was found to efficiently catalyze ST oxidatio

Construction of Biocatalysts Using the P450 Scaffold for the Synthesis of Indigo from Indole

With the increasing demand for blue dyes, it is of vital importance to develop a green and efficient biocatalyst to produce indigo. This study constructed a hydrogen peroxide-dependent catalytic system for the direct conversion of indole to indigo using P450BM3 with the assistance of dual-functional small molecules (DFSM). The arrangements of amino acids at 78, 87, and 268 positions influenced the catalytic activity. F87G/T268V mutant gave the highest catalytic activity with kcat of 1402 min−1 and with a yield of 73%. F87A/T268V mutant was found to produce the indigo product with chemoselectivity as high as 80%. Moreover, F87G/T268A mutant was found to efficiently catalyze indole oxidation with higher activity (kcat/Km = 1388 mM−1 min−1) than other enzymes, such as the NADPH-dependent P450BM3 (2.4-fold), the Ngb (32-fold) and the Mb (117-fold). Computer simulation results indicate that the arrangements of amino acid residues in the active site can significantly affect the catalytic activity of the protein. The DFSM-facilitated P450BM3 peroxygenase system provides an alternative, simple approach for a key step in the bioproduction of indigo

Spiro-Oxindole Skeleton Compounds Are Efficient Inhibitors for Indoleamine 2,3-Dioxygenase 1: An Attractive Target for Tumor Immunotherapy

Indoleamine 2,3-dioxygenase 1 (IDO1) is an attractive heme enzyme for its significant function in cancer immunotherapy. Potent IDO1 inhibitors have been discovered for decades, whereas no clinical drugs are used for cancer treatment up to now. With the goal of developing medically valuable IDO inhibitors, we performed a systematic study of SAR405838 analogs with a spiro-oxindole skeleton in this study. Based on the expression and purification of human IDO1, the inhibitory activity of spiro-oxindole skeleton compounds to IDO1 was evaluated by IC50 and Ki values. The results demonstrated that inhibitor 3 exhibited the highest IDO1 inhibitory activity with IC50 at 7.9 μM among all inhibitors, which is ~six-fold of the positive control (4−PI). Moreover, inhibitor 3 was found to have the most effective inhibition of IDO1 in MCF-7 cancer cells without toxic effects. Molecular docking analysis revealed that the hydrophobic interaction stabilized the binding of inhibitor 3 to the IDO1 active site and made an explanation for the uncompetitive mode of inhibitors. Therefore, this study provides valuable insights into the screen of more potent IDO1 inhibitors for cancer immunotherapy

The C-H-O Isotopic Composition and Significance of Spodumene for Redamen Pegmatite Type Rare Metal Deposit in Western Sichuan

The Redamen rare metal deposit is located in the south western part of Keeryin pegmetite typed ore field in western Sichuan. It is a special deposit in the aspects of surrounding rock, element mineralization zoning and distance. The ore with different elevation (3540~3830 m) of the same vein and the same orebody is systematically collected, spodumene single mineral is selected to analyze the C-H-O isotope composition and features of inclusions in different minerals.The inclusions in minerals are mainly liquid-rich inclusions. The salinity of the inclusions in spodumene is 8%~20%, and the homogenization temperature is 180~330℃. The inclusions belong to the ore-forming fluid with medium-low salinity and medium-high temperature. The inclusions in quartz have salinity of 0%~8%, homogenization temperature of 150~240℃, and belong to low salinity and low temperature fluid. The results of C-H-O isotope test show that the δD/‰ of spotamene in the Redamen rare metal deposit ranges from -97.5 to -104.7 (average of -102.8). Compared with the Lijiagou deposit in the southeast of the ore field, the δD/‰ of spodumene is obviously smaller, with the δ18OH2O/‰ ranging from -0.34 to 2.88 (average of 1.032). However, it is basically consistent with the main metallogenic period of spodumene in Lijiagou deposit, indicating that the ore-forming fluid of late mineralization (that is, the main metallogenic period of spodumene) is mixed with meteoric water. The δ13CV-PDB/‰ of spodumene in the Redamen rare metal deposit ranges from -10 to -16.6, with an average of -12.7, indicating that the carbon source in the main mineralization period (spodumene formation period) has a mixed nature of magmatic system and meteoric precipitation system, which is related to the low temperature alteration of magmatic mantle source (granite, mantle multi-phase system) and may be mixed with CO2 generated by the decarboxylation of deposited organic materials. Through the study of mineral C-H-O isotopes and fluid inclusions, the source and evolution process of ore-forming fluids were further clarified

Endophytic bacterial communities and spatiotemporal variations in cotton roots in Xinjiang, China

Endophytic bacteria may be important for plant health and other ecologically relevant functions of cotton. However, the endophytic bacterial community structure and diversity in cotton is still poorly characterized. We investigated the community structure of endophytic bacteria in cotton roots growing in Xinjiang, China, using the Illumina amplicon sequencing. A total of 60.84 M effective sequences of 16S rRNA gene V3 region were obtained from cotton samples. These sequences revealed huge amount of operational taxonomic units (OTUs) in cotton, that is, 81-338 OTUs in a cotton sample, at 3% cutoff level and sequencing depth of 50000 sequences. We identified 23 classes from the resulting 2,723,384 sequences. Gammaproteobacteria were the dominant class in all cottons, followed by Alphaproteobacteria, Actinobacteria and Bacilli. A marked difference in the diversity of endophytic bacteria in cotton for different growth periods was evident. The greatest number of OTUs was detected during seedling (654 OTUs) and budding (381 OTUs). Endophytic bacteria diversity was reduced during flowering (350 OTUs) and boll-opening (351 OTUs). 217 OTUs were common to all four periods. There were more tags of Pantoea in Shihezi than other locations. While there were more tags of Erwinia in Hami than other locations. The dynamics of endophytic bacteria communities were influenced by plant growth stage. These results show the complexity of the bacterial populations present in inner tissues of cotton.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Diversity and space–time dynamics of the bacterial communities in cotton (Gossypium hirsutum) rhizosphere soil

Rhizosphere bacteria are key determinants of plant health and productivity. In this study, we used PCR-based next-generation sequencing to reveal the diversity and community composition of bacteria in the cotton rhizosphere from samples collected in Xinjiang Province, China. We identified 125 bacterial classes within 49 phyla from these samples. Proteobacteria (33.07% of total sequences), Acidobacteria (19.88%), and Gemmatimonadetes (11.19%) dominated the bacterial community. Marked differences were evident in the α-diversity of rhizosphere bacteria during different cotton plant growth and development stages. The operational taxonomic unit (OTU) numbers were highest in seedling and bud stages and decreased at the flowering and fruit-boll-opening stages. Forty-three OTUs from the Proteobacteria were common to all four periods of cotton development. Proteobacteria were more abundant in the rhizospheres of cotton from southern Xinjiang than from northern Xinjiang, while the opposite trend was observed for Acidobacteria. Gemmatimonadetes frequency was broadly the same in both northern and southern Xinjiang. These results suggest that there is abundant diversity in the microbiota of cotton rhizosphere soil. Proteobacteria and Actinobacteria dominated this microbial niche and bacterial communities in the seedling, bud, flowering, and boll-opening stages appear to be more similar to one another than to communities at the other growth stages.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author