The highest plateau on Earth, Qinghai-Tibet Plateau, contains thousands of lakes with broad salinity and diverse and unique microbial communities. However, little is known about their co-occurring viruses. Herein, we identify 4,560 viral Operational Taxonomic Units (vOTUs) from six viromes of three saline lakes on Qinghai-Tibet Plateau, with less than 1% that could be classified. Most of the predicted vOTUs were associated with the dominant bacterial and archaeal phyla. Virus-encoded auxiliary metabolic genes suggest that viruses influence microbial metabolisms of carbon, nitrogen, sulfur, and lipid; the antibiotic resistance mediation; and their salinity adaption. The six viromes clustered together with the ice core viromes and bathypelagic ocean viromes and might represent a new viral habitat. This study has revealed the unique characteristics and potential ecological roles of DNA viromes in the lakes of the highest plateau and established a foundation for the recognition of the viral roles in plateau lake ecosystems.
The marine bacterial family Oceanospirillaceae, is well-known for its ability to degrade hydrocarbons and for its close association with algal blooms. However, only a few Oceanospirillaceae-infecting phages have been reported thus far. Here, we report on a novel Oceanospirillum phage, namely, vB_OsaM_PD0307, which has a 44,421 bp linear dsDNA genome and is the first myovirus infecting Oceanospirillaceae. A genomic analysis demonstrated that vB_OsaM_PD0307 is a variant of current phage isolates from the NCBI data set but that it has similar genomic features to two high-quality, uncultured viral genomes identified from marine metagenomes. Hence, we propose that vB_OsaM_PD0307 can be classified as the type phage of a new genus, designated Oceanospimyovirus. Additionally, metagenomic read mapping results have further shown that Oceanospimyovirus species are widespread in the global ocean, display distinct biogeographic distributions, and are abundant in polar regions. In summary, our findings expand the current understanding of the genomic characteristics, phylogenetic diversity, and distribution of Oceanospimyovirus phages. IMPORTANCE Oceanospirillum phage vB_OsaM_PD0307 is the first myovirus found to infect Oceanospirillaceae, and it represents a novel abundant viral genus in polar regions. This study provides insights into the genomic, phylogenetic, and ecological characteristics of the new viral genus, namely Oceanospimyovirus.
The quality of Panax Linn products available in the market is threatened by adulteration with different Panax species, such as Panax quinquefolium (PQ), Panax ginseng (PG), and Panax notoginseng (PN). In this paper, we established a 2D band-selective heteronuclear single quantum coherence (bs-HSQC) NMR method to discriminate species and detect adulteration of Panax Linn. The method involves selective excitation of the anomeric carbon resonance region of saponins and non-uniform sampling (NUS) to obtain high-resolution spectra in less than 10 min. The combined strategy overcomes the signal overlap limitation in 1H NMR and the long acquisition time in traditional HSQC. The present results showed that twelve well-separated resonance peaks can be assigned in the bs-HSQC spectra, which are of high resolution, good repeatability, and precision. Notably, the identification accuracy of species was found to be 100% for all tests conducted in the present study. Furthermore, in combination with multivariate statistical methods, the proposed method can effectively determine the composition proportion of adulterants (from 10% to 90%). Based on the PLS-DA models, the identification accuracy was greater than 80% when composition proportion of adulterants was 10%. Thus, the proposed method may provide a fast, practical, and effective analysis technique for food quality control or authenticity identification.
Dengue is an arthropod-borne infectious disease caused by dengue virus (DENV) infection and transmitted byAedesmosquitoes. Approximately 50-100 million people are infected with DENV each year, resulting in a high economic burden on both governments and individuals. Here, we conducted a systematic review and meta-analysis to summarize information regarding the epidemiology, clinical characteristics, and serotype distribution and risk factors for global dengue outbreaks occurring from 1990 to 2015. We searched the PubMed, Embase and Web of Science databases through December 2016 using the term "dengue outbreak." In total, 3,853 studies were identified, of which 243 studies describing 262 dengue outbreaks met our inclusion criteria. The majority of outbreak-associated dengue cases were reported in the Western Pacific Region, particularly after the year 2010; these cases were primarily identified in China, Singapore and Malaysia. The pooled mean age of dengue-infected individuals was 30.1 years; of the included patients, 54.5% were male, 23.2% had DHF, 62.0% had secondary infections, and 1.3% died. The mean age of dengue patients reported after 2010 was older than that of patients reported before 2010 (34.0 vs. 27.2 years); however, the proportions of patients who had DHF, had secondary infections and died significantly decreased after 2010. Fever, malaise, headache, and asthenia were the most frequently reported clinical symptoms and signs among dengue patients. In addition, among the identified clinical symptoms and signs, positive tourniquet test (OR= 4.86), ascites (OR= 13.91) and shock (OR= 308.09) were identified as the best predictors of dengue infection, DHF and mortality, respectively (bothP< 0.05). The main risk factors for dengue infection, DHF and mortality were living with uncovered water container (OR= 1.65), suffering from hypotension (OR= 6.18) and suffering from diabetes mellitus (OR= 2.53), respectively (allP< 0.05). The serotype distribution varied with time and across WHO regions. Overall, co-infections were reported in 47.7% of the evaluated outbreaks, and the highest pooled mortality rate (2.0%) was identified in DENV-2 dominated outbreaks. Our study emphasizes the necessity of implementing programs focused on targeted prevention, early identification, and effective treatment.
Whole-genome sequencing projects are increasingly populating the tree of life and characterizing biodiversity1-4. Sparse taxon sampling has previously been proposed to confound phylogenetic inference5, and captures only a fraction of the genomic diversity. Here we report a substantial step towards the dense representation of avian phylogenetic and molecular diversity, by analysing 363 genomes from 92.4% of bird families-including 267 newly sequenced genomes produced for phase II of the Bird 10,000 Genomes (B10K) Project. We use this comparative genome dataset in combination with a pipeline that leverages a reference-free whole-genome alignment to identify orthologous regions in greater numbers than has previously been possible and to recognize genomic novelties in particular bird lineages. The densely sampled alignment provides a single-base-pair map of selection, has more than doubled the fraction of bases that are confidently predicted to be under conservation and reveals extensive patterns of weak selection in predominantly non-coding DNA. Our results demonstrate that increasing the diversity of genomes used in comparative studies can reveal more shared and lineage-specific variation, and improve the investigation of genomic characteristics. We anticipate that this genomic resource will offer new perspectives on evolutionary processes in cross-species comparative analyses and assist in efforts to conserve species.
In Shanghai, the prevalence of tet(X4) and tet(X4)-carrying plasmid from food-producing -animal Enterobacteriales has not been intensively investigated. Here, five tet(X4)-positive swine-origin E. coli strains were characterized among 652 food-producing-animal E. coli isolates in Shanghai during 2018-2021 using long-term surveillance among poultry, swine and cattle, antimicrobial susceptibility testing, and tet(X4)-specific PCR. A combination of short- and long-read sequencing technologies demonstrated that the five strains with 4 STs carried a nearly identical 193 kb tet(X4)-bearing plasmid (p193k-tetX4) belonging to the same IncFIA(HI1)/IncHI1A/IncHIB plasmid family (p193k). Surprisingly, 34 of the 151 global tet(X4)-positive plasmids was the p193k members and exclusively pandemic in China. Other p193k members harboring many critically important ARGs (mcr or blaNDM) with particular genetic environment are widespread throughout human-animal-environmental sources, with 33.77 % human origin. Significantly, phylogenetic analysis of 203 p193k-tetX4 sequences revealed that human- and animal-origin plasmids clustered within the same phylogenetic subgroups. The largest lineage (173/203) comprised 161 E. coli, 6 Klebsiella, 3 Enterobacter, 2 Citrobacter, and 1 Leclercia spp. from animals (n = 143), humans (n = 18), and the environment (n = 9). Intriguingly, the earliest 2015 E. coli strain YA_GR3 from Malaysian river water and 2016 S. enterica Chinese clinical strain GX1006 in another lineage demonstrated that p193k-tetX4 have been widely spread from S. enterica or E. coli to other Enterobacterales. Furthermore, 180 E. coli p193k-tetX4 strains were widespread cross-sectorial transmission among food animals, pets, migratory birds, human and ecosystems. Our findings proved the extensive transmission of the high-risk p193k harboring crucial ARGs across multiple interfaces and species. Therefore, one-health-based systemic surveillance of these similar high-risk plasmids across numerous sources and bacterial species is extremely essential.