SecReT4: a web-based bacterial type IV secretion system resource.

SecReT4 (http://db-mml.sjtu.edu.cn/SecReT4/) is an integrated database providing comprehensive information of type IV secretion systems (T4SSs) in bacteria. T4SSs are versatile assemblages that promote genetic exchange and/or effector translocation with consequent impacts on pathogenesis and genome plasticity. T4SSs have been implicated in conjugation, DNA uptake and release and effector translocation. The effectors injected into eukaryotic target cells can lead to alteration of host cellular processes during infection. SecReT4 offers a unique, highly organized, readily exploreable archive of known and putative T4SSs and cognate effectors in bacteria. It currently contains details of 10 752 core components mapping to 808 T4SSs and 1884 T4SS effectors found in representatives of 289 bacterial species, as well as a collection of more than 900 directly related references. A broad range of similarity search, sequence alignment, phylogenetic, primer design and other functional analysis tools are readily accessible via SecReT4. We propose that SecReT4 will facilitate efficient investigation of large numbers of these systems, recognition of diverse patterns of sequence-, gene- and/or functional conservation and an improved understanding of the biological roles and significance of these versatile molecular machines. SecReT4 will be regularly updated to ensure its ongoing maximum utility to the research community.

MIST: A microbial identification and source tracking system for next-generation sequencing data.

The Professional Committee of Microbiology of the National Pharmacopoeia Commission organized the drafting of the Technical Guidelines for Microbial Whole Genome Sequencing (WGS), aiming to standardize the method process and technical indicators of microbial WGS and ensure the accuracy of sequencing and identification. On the basis of the Guidelines, we developed an integrated microbial identification and source tracking (MIST) system, which could meet the needs of microbial identification and contamination investigation in food and drug quality control. MIST integrates three analysis pipelines: 16S/18S/internal transcribed spacer amplicon-based microbial identification, WGS-based microbial identification, and single-nucleotide polymorphism-based microbial source tracking. MIST can analyze sequence data in a variety of formats, such as Fasta, base call file, and FASTQ. It can be connected to a high-throughput sequencing instrument to acquire sequencing data directly. We also developed a publicly accessible web server for MIST (http://syj.i-sanger.cn).

Zero-valent iron-induced successive chemical transformation and biodegradation of lindane in historically contaminated soil: An isotope-informed metagenomic study.

Zero-valent iron (ZVI) is widely used to mitigate environmental pollutants such as chlorinated pesticides through reductive reactions accompanied by extensive impacts on the soil microbial community. However, whether and how ZVI changes the biodegradation of target compounds remain poorly understood. Here, we monitor the fate of lindane using a 14C-labled tracer and evaluate the growth and functions of the bacterial community in ZVI-stressed conditions in a historically γ-hexachlorocyclohexane (lindane)-contaminated soil using a combination of isotopic (18O-H2O) and metagenomic methods. ZVI promoted the biomineralization of lindane in a dose-dependent manner. Soil bacteria were inhibited by amendment with ZVI during the initial stages of incubation (first three days) but recovered during the subsequent six weeks. Metagenomic study indicates that the todC1/bedC1 genes involved in the oxidation of dechlorinated lindane intermediates were upregulated in the 18O-labeled bacterial community but the presence of the lin genes responsible for lindane dechlorination was not confirmed. In addition, the benzoate biodegradation pathway that links to downstream catabolism of lindane was enhanced. These findings indicate successive chemical and biological degradation mechanisms underlying ZVI-enhanced lindane mineralization and provide a scientific basis for the inclusion of an extended bioremediation stage in the environmental application of ZVI materials.

Majorbio Cloud: A one-stop, comprehensive bioinformatic platform for multiomics analyses.

The platform consists of three modules, which are pre-configured bioinformatic pipelines, cloud toolsets, and online omics' courses. The pre-configured bioinformatic pipelines not only combine analytic tools for metagenomics, genomes, transcriptome, proteomics and metabolomics, but also provide users with powerful and convenient interactive analysis reports, which allow them to analyze and mine data independently. As a useful supplement to the bioinformatics pipelines, a wide range of cloud toolsets can further meet the needs of users for daily biological data processing, statistics, and visualization. The rich online courses of multi-omics also provide a state-of-art platform to researchers in interactive communication and knowledge sharing.

[Overview of antibiotic resistance genes database].

The discovery of antibiotics is a big revolution in human history, and its clinical application has saved countless lives. However, with the widespread and abuse of antibiotics, many pathogens have developed resistance, and even "Super Bacteria" resistance to multiple drugs have evolved. In the arms race between humans and pathogens, humans are about to face a situation where no medicine is available. Research on microbial antibiotic resistance genes, resistance mechanisms, and the spread of resistance has attracted the attention of many scientific researchers, and various antibiotic resistance gene databases and analysis tools have emerged. In this review, we collect the current databases that focus on antibiotics resistance genes, and discuss these databases in terms of database types, data characteristics, antibiotics resistance gene prediction models and the types of analyzable sequences. In addition, a few gene databases of anti-metal ions and anti-biocides are also involved. It is believed that this summary will provide a reference for how to select and use antibiotic resistance gene databases.

Gut microbiota dysbiosis worsens the severity of acute pancreatitis in patients and mice.

BACKGROUND: The gut is implicated in the pathogenesis of acute pancreatitis (AP) and the infectious complications of AP are commonly associated with enteric bacteria, yet whether gut microbiota dysbiosis participants in AP severity remains largely unknown. METHODS: We collected clinical information and fecal samples from 165 adult participants, including 41 with mild AP (MAP), 59 with moderately severe AP (MSAP), 30 with severe AP (SAP) and 35 healthy controls (HC). The serum inflammatory cytokines and gut barrier indexes were detected. Male C57BL/6 mice with AP were established and injuries of pancreas were evaluated in antibiotic-treated mice, germ-free mice as well as those transplanted with fecal microbiota. The gut microbiota was analyzed by 16S rRNA gene sequencing. RESULTS: The structure of gut microbiota was significantly different between AP and HC, and the disturbed microbiota was closely correlated with systematic inflammation and gut barrier dysfunction. Notably, the microbial composition changed further with the worsening of AP and the abundance of beneficial bacteria such as Blautia was decreased in SAP compared with MAP and MSAP. The increased capacity for the inferred pathway, bacterial invasion of epithelial cells in AP, highly correlated with the abundance of Escherichia-Shigella. Furthermore, the antibiotic-treated mice and germ-free mice exhibited alleviated pancreatic injury after AP induction and subsequent fecal microbiota transplantation in turn exacerbated the disease. CONCLUSIONS: This study identifies the gut microbiota as an important mediator during AP and its dysbiosis is associated with AP severity, which suggests its role as potential therapeutic target.

Expansion of Thaumarchaeota habitat range is correlated with horizontal transfer of ATPase operons.

Thaumarchaeota are responsible for a significant fraction of ammonia oxidation in the oceans and in soils that range from alkaline to acidic. However, the adaptive mechanisms underpinning their habitat expansion remain poorly understood. Here we show that expansion into acidic soils and the high pressures of the hadopelagic zone of the oceans is tightly linked to the acquisition of a variant of the energy-yielding ATPases via horizontal transfer. Whereas the ATPase genealogy of neutrophilic Thaumarchaeota is congruent with their organismal genealogy inferred from concatenated conserved proteins, a common clade of V-type ATPases unites phylogenetically distinct clades of acidophilic/acid-tolerant and piezophilic/piezotolerant species. A presumptive function of pumping cytoplasmic protons at low pH is consistent with the experimentally observed increased expression of the V-ATPase in an acid-tolerant thaumarchaeote at low pH. Consistently, heterologous expression of the thaumarchaeotal V-ATPase significantly increased the growth rate of E. coli at low pH. Its adaptive significance to growth in ocean trenches may relate to pressure-related changes in membrane structure in which this complex molecular machine must function. Together, our findings reveal that the habitat expansion of Thaumarchaeota is tightly correlated with extensive horizontal transfer of atp operons.