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Climate change is significantly impacting the geographic range of many animal species and their associated microorganisms, hence influencing emergence of vector-borne diseases. Mosquito-borne viruses represent a potential major reservoir of human pathogens, highlighting the need for improved understanding of ecological factors associated with variation in the mosquito viral community (virome). Here, a subtractive hybridization method coupled with RNAseq of individual mosquito specimens was used to profile RNA viromes of individual co-occurringAedes albopictusandAedes vexansmosquitoes across a 2,000 km spatial scale. Samples were collected and archived by the National Ecological Observatory Network (NEON) from four ecologically variable sites in the Southeastern United States between 2018 and 2019. Results of multivariate analysis suggest that mosquito species are an important factor in RNA viral community composition. Significantly higher viral diversity was detected inA. albopictuscompared toA.vexans. However, season, year, and site of sample collection did not show strong association with virome profiles, supporting the hypothesis that factors unique to the mosquito host species (e.g., larval habitat or vector competence) influence the structure of mosquito viromes. 

ABSTRACT Proliferation ofVibriospp. in aquatic ecosystems is associated with climate change and, concomitantly, increased incidence of vibriosis. They are autochthonous to aquatic environments globally, but traditional metagenomic methods for detecting and typing pathogenicVibriospp. are challenged by their presence in relatively low abundance and ability to persist in a viable but nonculturable state. In the study reported here, hybridization capture sequencing (HCS) was employed to profile low-abundanceVibriospp. in environmental samples. The HCS panel targeted a family of molecular chaperones (CPN60) specific to 69Vibriospp. and 162Vibrio-specific virulence factors. This approach was evaluated in parallel with traditional whole-community shotgun sequencing in a metagenomic analysis of water and oyster samples collected from the Chesapeake Bay. In addition,Vibrio parahaemolyticusandVibrio vulnificusstrains isolated from the samples were subjected to whole-genome sequencing to determine the genetic characteristics of pathogenicVibriospp. circulating in an aquatic environment. HCS, employed to determine the incidence and characterization of specificVibriospp., yielded significantly greater metagenomic insight, notably a variety of otherVibriospp., including detection ofVibrio cholerae,Vibrio fluvialis, andVibrio aestuarianus, in addition toVibrio parahaemolyticusandVibrio vulnificus, and also important virulence factors not detectable using traditional molecular methods. Thus, pathogenicVibriospp. in aquatic ecosystems may be far more common than currently understood. It is concluded that environmental surveillance should include HCS, a valuable tool for the detection and characterization of pathogenic agents in aquatic ecosystems, notably vibrios.IMPORTANCEThe increasing prevalence of pathogenicVibriospp. in aquatic ecosystems, driven by climate change, is closely linked to a rise in cholera and vibriosis cases, emphasizing the need for improved environmental surveillance. Vibrios are naturally occurring in aquatic environments globally, but traditional metagenomic methods for detecting and typing pathogenicVibriospp. are challenged by their presence in relatively low abundance and ability to persist in a viable but nonculturable state. In the study reported here, hybridization capture sequencing was employed to profile low-abundanceVibriospp. in metagenomic samples, namely water and oysters collected from the Chesapeake Bay. This approach was evaluated in parallel with traditional whole-community shotgun sequencing and whole-genome sequencing ofVibrio parahaemolyticusandVibrio vulnificusstrains isolated from the samples. Results suggest pathogenicVibriospp. in aquatic ecosystems may be far more common than currently understood, when multiple methods are considered for environmental surveillance. 

We hypothesize that bacteria isolated from free-ranging animals could potentially be useful for practical applications. To meet this objective a Gram-positive bacterium was isolated from the gastrointestinal (GI) tract of a Gray Wolf (Canis lupus) using Brucella broth with hemin and vitamin K (BBHK). By small ribosomal RNA (16S) gene sequencing the bacterium was initially identified as a novel Carnobacterium maltaromaticum strain. The bacterium could be propagated both anaerobically and aerobically and was both catalase/oxidase negative and negative by the starch hydrolysis as well as negative using lipase assays. The reference whole genome sequence (WGS) was obtained using both Illumina and Nanopore sequencing. The genome assembly was 3,512,202 bp in length, encoding core bacterial genes with a GC% content of 34.48. No lysogenic bacteriophage genes were detected, although the genome harbors genes for the expression of bacteriocin and other secondary metabolites with potential antimicrobial properties. Multilocus sequence typing (MLST), WGS phylogenetics, average nucleotide identity (ANI), and single nucleotide polymorphism (SNP) analyses of the isolate’s genome indicate this bacterium is a newly identified Carnobacterium maltaromaticum sequence type (ST). Members of the Carnobacteria have anti-listeria activities, highlighting their potential functional properties. Consequently, the isolate could be a potential probiotic for canids and this is the first report on an axenic C. maltaromaticum culture from the genus Canis. 

Inflammatory bowel disease (IBD) is increasing among mammals around the world, and domestic dogs are no exception. There is no approved cure for canine IBD with limited treatment options. Novel probiotic bacteria discovery from free-ranging animals for the treatment of IBD in domestic pets can likely yield promising probiotic candidates. Consequently, the overall aim was to isolate bacteria from free-ranging animals that could potentially be utilized as novel probiotics. Two bacteria identified as unique Paenibacillus spp. strains by small ribosomal RNA (16S) gene sequencing were isolated from the gastrointestinal tract of a North American Gray Wolf (Canis lupus). The bacteria were typed as Gram-variable, and both were catalase/oxidase positive as well as sensitive to commonly used antibiotics. The bacteria digested complex carbohydrates and lipids by standard assays. The isolated bacteria also inhibited the growth of Staphylococcus aureus and Micrococcus luteus. The whole genome sequence (WGS) length of bacterial isolate ClWae17B was 6,939,193 bp, while ClWae19 was 7,032,512 bp, both similar in size to other Paenibacillus spp. The genomes of both bacteria encoded enzymes involved with the metabolism of complex starches and lipids, such as lyases and pectinases, along with encoding antimicrobials such as lanthipeptides, lasso peptides, and cyclic-lactone-autoinducers. No pernicious virulence genes were identified in the WGS of either bacterial isolate. Phylogenetically, the most closely related bacteria based on 16S gene sequences and WGS were P. taichungensis for ClWae17B and P. amylolyticus for ClWae19. WGS analyses and phenotypic assays supported the hypothesis that the isolates described constitute two novel candidate probiotic bacteria for potential use in dogs. 

Abstract Periodical cicadas ( Hemiptera : Magicicada ) have coevolved with obligate bacteriome-inhabiting microbial symbionts, yet little is known about gut microbial symbiont composition or differences in composition among allochronic Magicicada broods (year classes) which emerge parapatrically or allopatrically in the eastern United States. Here, 16S rRNA amplicon sequencing was performed to determine gut bacterial community profiles of three periodical broods, including II (Connecticut and Virginia, 2013), VI (North Carolina, 2017), and X (Maryland, 2021, and an early emerging nymph collected in Ohio, 2017). Results showed similarities among all nymphal gut microbiomes and between morphologically distinct 17-year Magicicada , namely Magicicada septendecim (Broods II and VI) and 17-year Magicicada cassini (Brood X) providing evidence of a core microbiome, distinct from the microbiome of burrow soil inhabited by the nymphs. Generally, phyla Bacteroidetes [ Bacteroidota ] (> 50% relative abundance), Actinobacteria [ Actinomycetota ], or Proteobacteria [ Pseudomonadota ] represented the core. Acidobacteria and genera Cupriavidus , Mesorhizobium , and Delftia were prevalent in nymphs but less frequent in adults. The primary obligate endosymbiont, Sulcia ( Bacteroidetes ), was dominant amongst core genera detected. Chryseobacterium were common in Broods VI and X. Chitinophaga, Arthrobacter , and Renibacterium were common in Brood X, and Pedobacter were common to nymphs of Broods II and VI. Further taxonomic assignment of unclassified Alphaproteobacteria sequencing reads allowed for detection of multiple copies of the Hodgkinia 16S rRNA gene, distinguishable as separate operational taxonomic units present simultaneously. As major emergences of the broods examined here occur at 17-year intervals, this study will provide a valuable comparative baseline in this era of a changing climate. 

Microbial contamination of recreation waters is a major concern globally, with pollutants originating from many sources, including human and other animal wastes often introduced during storm events. Fecal contamination is traditionally monitored by employing culture methods targeting fecal indicator bacteria (FIB), namely E . coli and enterococci, which provides only limited information of a few microbial taxa and no information on their sources. Host-associated qPCR and metagenomic DNA sequencing are complementary methods for FIB monitoring that can provide enhanced understanding of microbial communities and sources of fecal pollution. Whole metagenome sequencing (WMS), quantitative real-time PCR (qPCR), and culture-based FIB tests were performed in an urban watershed before and after a rainfall event to determine the feasibility and application of employing a multi-assay approach for examining microbial content of ambient source waters. Cultivated E . coli and enterococci enumeration confirmed presence of fecal contamination in all samples exceeding local single sample recreational water quality thresholds ( E . coli , 410 MPN/100 mL; enterococci, 107 MPN/100 mL) following a rainfall. Test results obtained with qPCR showed concentrations of E . coli , enterococci, and human-associated genetic markers increased after rainfall by 1.52-, 1.26-, and 1.11-fold log 10 copies per 100 mL, respectively. Taxonomic analysis of the surface water microbiome and detection of antibiotic resistance genes, general FIB, and human-associated microorganisms were also employed. Results showed that fecal contamination from multiple sources (human, avian, dog, and ruminant), as well as FIB, enteric microorganisms, and antibiotic resistance genes increased demonstrably after a storm event. In summary, the addition of qPCR and WMS to traditional surrogate techniques may provide enhanced characterization and improved understanding of microbial pollution sources in ambient waters.