The Construction of a Microbial Synthesis System for Rare Earth Enrichment and Material Applications.

Rare earth materials play an irreplaceable role in biomedical and high technology fields. However, typical mining and extraction approaches to rare earth elements (REEs) often lead to severe environmental problems and resource wastage due to the involvement of hazardous chemicals. Although biomining shows elegant alternatives, there are still grand challenges to sustainably isolate and recover REEs in nature because of insufficient metal-extracting microbes and RE-scavenging macromolecular tools. To obtain high-performance rare earth materials directly from rare earth ore, a new generation of biological synthesis strategies needs to be developed for the efficient preparation of REEs. The microbial synthesis system established here has achieved active biomanufacturing of high-purity rare earth products. Further, through employing robust affinity columns bioconjugated with structurally engineered proteins, outstanding separation of Eu/Lu and Dy/La is acquired with the purity of 99.9% (Eu), 97.1% (La), and 92.7% (Dy). More importantly, in situ one-pot synthesis of lanthanide-dependent methanol dehydrogenase is well harnessed and exclusively adsorbs La, Ce, Pr, and Nd in RE tailing for advanced biocatalysis, indicating high value-added application. Therefore, this novel biosynthetic platform provides an insightful roadmap to expand the scope of chassis engineering in terms of biofoundry and to manufacture valuable bioproducts related to REEs.

Microbial and enzymatic battle with food contaminant zearalenone (ZEN).

Zearalenone (ZEN) contamination of various foods and feeds is an important global problem. In some animals and humans, ZEN causes significant health issues in addition to massive economic losses, annually. Therefore, removal or degradation of the ZEN in foods and feeds is required to be done. The conventional physical and chemical methods have some serious issues including poor efficiency, decrease in nutritional value, palatability of feed, and use of costly equipment. Research examined microbes from diverse media for their ability to degrade zearalenone and other toxins, and the findings of several investigations revealed that enzymes produced from microbes play a significant role in the degradation of mycotoxins. In established bacterial hosts, genetically engineered technique was used to enhance heterologously produced degrading enzymes. Then, the bio-degradation of ZEN by the use of micro-organisms or their enzymes is much more advantageous and is close to nature and ecofriendly. Furthermore, an effort is made to put forward the work done by different scientists on the biodegradation of ZEN by the use of fungi, yeast, bacteria, and/or their enzymes to degrade the ZEN to non-toxic products. KEY POINTS: •Evolved microbial strains degraded ZEA more quickly •Different degrading properties were studied.

Isolation, characterization and comparison of lytic Epseptimavirus phages targeting Salmonella.

This study describes the characterization and genomic analysis of six lytic Salmonella phages. To examine the feasibility of using these phages as biocontrol agents, we analyzed their genomes and compared them to those of similar phages. These six phages belong to genus Epseptimavirus, family Demerecviridae. We identified the genes of these six phages by comparing their genomes with those of three type phages in subfamily Markadamsvirinae. All six phages examined in this study were obligately lytic and did not carry undesirable genes. Two phages (vB_SalS_1-23 and vB_SalS_3-29) were selected as the representative phages for general characterization and physiological tests. The biocontrol efficacy of the representative phages was determined by comparing the viable counts of recovered host Salmonella ser. Newlands ZC-S1 from treatment and phage-free control samples. The biocontrol experiment showed that the representative phages were able to reduce the counts of ZC-S1 to below 2 log10 CFU/mL (~4.3 log10 CFU/mL reduction) at 3 h post-infection at 37 °C. Furthermore, we investigated the application of these two phages in the control of ZC-S1 contamination in chicken products and on eggshells. When applied to the surfaces of the samples, the phage cocktail (MOI = 100) reduced the ZC-S1 count to below 2 log10 CFU/mL on chicken skin and to undetectable levels (1 log10 CFU/mL) in chicken breast meat, ground chicken meat and eggshell samples (p < 0.01). Compared to the initial experiment, the phage cocktail reduced the ZC-S1 count by 2-4.08 log10 CFU/mL when applied at an MOI = 1 (except in the ground chicken meat group) and by 4.48-5.67 log10 CFU/mL at an MOI = 100 after 7 h. In conclusion, these two phages with lytic effects show a high potential to inhibit the growth of Salmonella contaminants and can be used as candidate biocontrol agents.

The endolysin of the Acinetobacter baumannii phage vB_AbaP_D2 shows broad antibacterial activity.

The emergence and rapid spread of multidrug-resistant bacteria has induced intense research for novel therapeutic approaches. In this study, the Acinetobacter baumannii bacteriophage D2 (vB_AbaP_D2) was isolated, characterized and sequenced. The endolysin of bacteriophage D2, namely Abtn-4, contains an amphipathic helix and was found to have activity against multidrug-resistant Gram-negative strains. By more than 3 log units, A. baumannii were killed by Abtn-4 (5 µM) in 2 h. In absence of outer membrane permeabilizers, Abtn-4 exhibited broad antimicrobial activity against several Gram-positive and Gram-negative bacteria, such as Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumonia, Enterococcus and Salmonella. Furthermore, Abtn-4 had the ability to reduce biofilm formation. Interestingly, Abtn-4 showed antimicrobial activity against phage-resistant bacterial mutants. Based on these results, endolysin Abtn-4 may be a promising candidate therapeutic agent for multidrug-resistant bacterial infections.

Profiles of COVID-19 clinical trials in the Chinese Clinical Trial Registry.

The COVID-19 pandemic has caused a global public health crisis. There is a pressing need for evidence-based interventions to address the devastating clinical and public health effects of the COVID-19 pandemic. The Chinese scientists supported by private and government resources have adopted extensive efforts to identify effective drugs against the virus. To date, a large number of clinical trials addressing various aspects of COVID19 have been registered in the Chinese Clinical Trial Registry (ChiCTR), including more than 200 interventional studies. Under such an urgent circumstance, the scope and quality of these clinical studies vary significantly. Hence, this review aims to make a comprehensive analysis on the profiles of COVID-19 clinical trials registered in the ChiCTR, including a wide range of characteristics. Our findings will provide a useful summary on these clinical studies since most of these studies will encounter major challenges from the design to completion. It will be a long road for the outcomes of these studies to be published and international collaboration will help the ultimate goals of developing new vaccines and anti-viral drugs.

Complete genome analysis of a Staphylococcus aureus phage (vBSM-A1).

In this study, the genome of a new strain of lytic Staphylococcus aureus Herelleviridae, vBSM-A1, was characterized and annotated. The phage was isolated from sewage samples collected in Xinjiang Province, China. The genome of vBSM-A1 was found to comprise a linear double-stranded DNA of 140,654 bp length, with a G + C content of 30.33%. A total of 215 ORFs were detected in the phage DNA, 74 of which were functionally assigned. The 3D structure model of endolysin LysK (ORF 143) was created using Phyre2.

Complete genome analysis of the novel Edwardsiella tarda phage vB_EtaM_ET-ABTNL-9.

This work describes the characterization and genome annotation of a new lytic phage, vB_EtaM_ET-ABTNL-9 (referred to as PETp9), isolated from waste water samples collected in Dalian, China, that can kill bacteria of the species Edwardsiella tarda. The genome of phage PETp9 is a circular double-stranded DNA molecule that is 89,762 bp in length with a G+C content of 37.26%, contains 132 ORFs, and encodes one tRNA. Phylogenetic analysis indicated that phage PETp9 should be considered a novel phage.

Interleukin-24 Concentrations Not Related with Age, but Affect Pro- and Anti-Inflammatory Cytokines Differently in Healthy Donors.

BACKGROUND: Interleukin 24 (IL-24) is expressed at different levels in a variety of tumor tissues and matched normal tissues and is regarded as a potential tumor biomarker as its expression levels in tumor tissues are associated with tumor patient prognosis. At present, the expression level of IL-24 in healthy human peripheral blood is unknown. METHODS: In this study, 1940 blood samples were collected using different processing methods from healthy donors. ELISA was used to detect IL-24 concentrations. RESULTS: The results showed that processing methods had the greatest influence on test results, with the highest IL24 concentration in EDTA plasma and the lowest in sodium citrate plasma. Lengths of storage time at 4°C had no obvious effect on IL-24 test results, and IL-24 in peripheral blood was stable for 15 days. IL-24 concentration in the sera of healthy donors showed no associations with age, blood glucose, hemoglobin, total cholesterol, carcinoembryonic antigen, absolute lymphocyte counts, alpha fetoprotein, white blood cells, thyroid stimulating hormone, or cereal third transaminase. We also confirmed that IL-24 expression level in the blood of healthy subjects was positively correlated with pro-inflammatory cytokines, tumor necrosis factor-alpha (TNF-α), and interleukin 6 (IL-6), but negatively correlated with anti-inflammatory cytokine, IL-10. CONCLUSIONS: We observed that sample processing methods influence the detection of IL-24 levels as EDTA plasma had the highest IL-24 concentration, and citric acid sodium, the lowest. Age, gender, and physical and chemical indicators were not related to IL-24 concentrations. We confirmed the IL-24 concentration was positively related to IL-6 and TNF-α and negatively to IL-10.