Genome-wide identification and expression analysis of magnesium transporter gene family in grape (Vitis vinifera).

BACKGROUND: Magnesium ion is one of the essential mineral elements for plant growth and development, which participates in a variety of physiological and biochemical processes. Since there is no report on the research of magnesium ion transporter in grape, the study of the structure and function of magnesium ion transporters (MGT) is helpful to understand the dynamic balance mechanism of intracellular magnesium ions and their inter- or intra-cellular activities. RESULT: In this study, we identified the members of MGT protein family in grape and performed the phylogenetic and expression analysis. We have identified nine VvMGT genes in grape genome, which are distributed on eight different chromosomes. Phylogenetic analysis showed that MGT family members of grapes were divided into five subfamilies and had obvious homology with Arabidopsis, maize, and pear. Based on transcriptome data from the web databases, we analyzed the expression patterns of VvMGTs at different development stages and in response to abiotic stresses including waterlogging, drought, salinity, and copper. Using qRT-PCR method, we tested the expression of grape VvMGTs under magnesium and aluminum treatments and found significant changes in VvMGTs expression. In addition, four of the MGT proteins in grape were located in the nucleus. CONCLUSION: Overall, in this study we investigated the structural characteristics, evolution pattern, and expression analysis of VvMGTs in depth, which laid the foundation for further revealing the function of VvMGT genes in grape.

Transcriptomic analysis reveals that the small protein MgtS contributes to the virulence of uropathogenic Escherichia coli.

Uropathogenic Escherichia coli (UPEC) is the most common pathogen causing urinary tract infections (UTIs). The pathogenesis of UPEC relies on the formation of intracellular bacterial communities (IBCs) after invading bladder epithelial cells (BECs). In this study, the gene expression profiles of UPEC after invading BECs were comprehensively analyzed using RNA sequencing to reveal potential virulence-related genes. The small protein MgtS, which is transcriptionally upregulated in BECs, was further investigated. It was found that MgtS contributed positively to UPEC invasion of BECs and colonization in murine bladders. A two-component regulatory system, PhoPQ was confirmed as a direct activator of mgtS expression in BECs, and magnesium limitation is proposed as a host cue for the activation. This study provides the first comprehensive analysis of the transcriptome profile of UPEC during its intra-BECs life, revealing a new virulence-associated gene and its regulatory mechanism.

[Removal Performance of Antibiotic Resistance Genes and Heavy Metal Resistance Genes in Municipal Wastewater by Magnetic-Coagulation Process].

Antibiotic resistance genes (ARGs) in municipal wastewater pose a potential threat to the environment. In this study, the change in absolute and relative abundance of ARGs, metal resistance genes (MRGs), and mobile genetic elements (MGTs) were investigated during an emergent municipal wastewater treatment by the magnetic separation process. Results indicate that all the concentrations of targeted ARGs, MRGs, and MGTs decreased significantly in the primary and secondary stirring tank. However, the absolute abundance of some ARGs and MRGs increased in the effluent, which is likely caused by the presence of ample MGTs, in the order of int1 (2.00×1010 copies·mL-1) > int2 (1.91×108 copies·mL-1) > Tn 916/1545e(5.38×108 copies·mL-1). The results obtained from network and PCA analysis showed that the removal of ARGs and MRGs were significantly associated with variations in the microbial community and common pollutants in urban wastewater, such as suspended solids, phosphorus, and COD, which are important factors for affecting the removal efficiency of antibiotic resistance genes and metal heavy resistance genes. These results show that magnetic separation can effectively reduce common pollutants in urban wastewater and might further restrict the transmission and transfer of ARGs. Moreover, it is necessary to strengthen the subsequent management of magnetic separation effluent and dehydrated sludge by disinfection technologies to lessen the risk of antimicrobial contamination.