Search Results (16)

The surveillance of wildlife viromes is essential for identifying zoonotic threats within the One Health framework. This study analyzed rectal and oral swabs from 88 individuals representing 13 species as felids, wild rodents, marsupials and non-human primates in Southern Brazil using metagenomic sequencing. Akodon montensis (n = 15 individuals) and Coendou spinosus (n = 4) harbored Chikungunya virus (ChikV, Togaviridae), marking its first detection in these hosts. Molossus molossus (n = 17) presented Coronaviridae and Orthoherpesviridae, while Eptesicus furinalis (n = 1) also carried Coronaviridae. A broad virome diversity, including Togaviridae and Adenoviridae members, was identified in Didelphis albiventris (n = 43), with significant relevance to human health. Additional species, such as Callithrix jacchus (n = 1), Leopardus guttulus (n = 1), Myocastor coypus (n = 1), Monodelphis iheringi (n = 1), Thaptomys nigrita (n = 1), Sooretamys angouya (n = 1), Brucepattersonius iheringi (n = 1), and Lasiurus blossevillii (n = 1), contributed to insights into viral reservoirs. These results underscore the importance of virome studies in regions harboring high biodiversity, emphasizing genomic surveillance as a vital tool for monitoring zoonotic viruses and safeguarding global health. Full article

Coronaviruses (CoV) infect a wide variety of hosts, causing epidemics in humans, birds, and mammals over the years. Bats (order Chiroptera) are one of the natural hosts of the Coronaviridae family. They represent 40% of the total number of mammal species in the Pantanal, a biodiversity hotspot in South America. Given the recent SARS-CoV-2 pandemic, we investigated the presence of CoV in bats captured in the Brazilian Pantanal. Oral and rectal swabs collected in 2021 from 419 bats were analyzed using Pancoronavirus-nested PCR targeting the RNA-dependent RNA-polymerase (RdRp) gene. Orthocoronavirinae was detected in 16.7% (70/419) of the bats; nine samples were sequenced, confirming that Carollia perspicillata (4), Phyllostomus hastatus (2), Desmodus rotundus (1), Molossus rufus (1), and Myotis cf. nigricans (1) collected in buildings formally used by humans were infected by Alphacoronavirus genera. This is the first description of Alphacoronavirus in bats from the Pantanal. As they are natural reservoirs of CoVs, constant monitoring of bats is important to comprehend the epidemiology of emerging viruses, especially in the Pantanal biome. Full article

To date, limited information is available on herpesviruses in bats from the Caribbean region. We report here high detection rates (24.24%, n = 66) of herpesviruses in oral samples from apparently healthy bats (Ardops nichollsi (75%, 9/12) and Molossus molossus (28%, 7/25)) on the Lesser Antillean Island of St. Kitts. Based on analysis of partial DNA polymerase (DPOL) sequences (~225 amino acid (aa) residues), we identified two distinct groups of herpesviruses (BO-I and -II) that were unique to A. nichollsi and M. molossus, respectively. Within the subfamily Betaherpesvirinae, the BO-I DPOL sequences shared low deduced aa identities (<70%) with other herpesviruses, and phylogenetically, they formed a distinct cluster, representing a putative novel betaherpesvirus. The BO-II DPOL sequences were closely related to a putative novel betaherpesvirus from a M. molossus in Lesser Antillean Island of Martinique, indicating possible transmission of herpesviruses by bat movement between the Caribbean Islands. Phylogenetically, the BO-I and -II betaherpesviruses exhibited species-specific (A. nichollsi and M. molossus, respectively) as well as family-specific (Phyllostomidae and Molossidae, respectively) clustering patterns, corroborating the hypothesis on host specificity of betaherpesviruses. Interestingly, a single M. molossus betaherpesvirus strain clustered with the A. nichollsi betaherpesviruses, indicating possible interspecies transmission of herpesviruses between Phyllostomidae and Molossidae. To our knowledge, this is the first report on detection of herpesviruses from Antillean tree bats (A. nichollsi), expanding the host range of betaherpesviruses. Taken together, the present study identified putative novel betaherpesviruses that might be unique to chiropteran species (A. nichollsi and M. molossus), indicating virus–host coevolution, and provided evidence for interspecies transmission of betaherpesviruses between chiropteran families. Full article

The Asian dung beetle (Catharsius molossus L.; Coleoptera: Scarabeidae) has been shown to positively affect soil bacterial diversity and the agronomic features of crop plants. In this study, we used bioinformatic tools to investigate the differences in bacterial functional phenotypes and ecological functions between control soil, cow dung-amended soil (CD), and cow dung-amended soil composted by dung beetles (DB). The soil bacterial metagenomes were sequenced and analyzed with the bioinformatic packages BugBase, PICRUSt2, Tax4Fun, and FAPROTAX to evaluate the effects of dung beetle-mediated composting on bacterial functions such as human and plant pathogenicity, trophic strategies, and soil nutrient transformation. BugBase proved useful for the determination of differences in major functional phenotypes, whereas FAPROTAX was effective at identifying differences in bacterial ecological functions between the treatments. Both tools suggested a relative decrease in human pathogens in the DB soil. This was corroborated by the pairwise comparison of abundances in bacterial species, which showed a significant reduction in the abundance of the broad-host-range pathogen Pseudomonas aeruginosa in the DB soil. In addition, FAPROTAX suggested a decrease in plant pathogens and an increase in chitinolytic bacteria, meaning that the DB treatment might be beneficial to the plant-growth-promoting bacteria involved in biological control. Finally, FAPROTAX revealed an array of ecological functions related to trophic strategies and macro- and micronutrient metabolism. According to these results, the activity of C. molossus beetles enhanced methanotrophy, ammonification, nitrification, sulfate reduction, and manganese oxidation, whereas iron respiration was decreased in the DB-treated soil. Our results represent a collection of general insights into the effects of C. molossus beetles on soil bacterial functions, which also reflect on the nutrient composition of dung beetle-composted soil. Full article

The causative agent of Chagas disease is Trypanosoma cruzi, which is widely distributed throughout the South American continent and extends into North America. Its occurrence in bats is poorly described and may impact the disease’s maintenance and epidemiology. The aim of this study was to detect the agent by PCR assays targeting kDNA and nuclear DNA in the organs of 203 urban bats and rural vampire bats from the Brazilian Atlantic Forest, São Paulo state, during the pandemic period from 2020 to 2022. In total, 6 of the 203 bats (2.97%) were positive for T. cruzi. Infection was detected in 2% (2/101) of Desmodus rotundus, 33% (1/3) of Nyctinomops laticaudatus, 25% (1/4) of Artibeus lituratus, 4% (1/24) of Eumops glaucinus and in 2% (1/41) of Molossus molossus. The gene sequences obtained were assessed for quality and deposited in a public repository. Fruit bats were statistically associated with positivity for T. cruzi. To our knowledge, this study detected T. cruzi for the first time in bats from São Paulo state and in N. laticaudatus and E. glaucinus species. Full article

CRESS-DNA encompasses a broad spectrum of viruses documented across diverse organisms such as animals, plants, diatoms, fungi, and marine invertebrates. Despite this prevalence, the full extent of these viruses’ impact on the environment and their respective hosts remains incompletely understood. Furthermore, an increasing number of viruses within this category lack detailed characterization. This investigation focuses on unveiling and characterizing viruses affiliated with the Genomoviridae family identified in liver samples from the bat Molossus molossus. Leveraging viral metagenomics, we identified seven sequences (MmGmV-PA) featuring a circular DNA genome housing two ORFs encoding replication-associated protein (Rep) and capsid protein (Cap). Predictions based on conserved domains typical of the Genomoviridae family were established. Phylogenetic analysis revealed the segregation of these sequences into two clades aligning with the genera Gemycirculavirus (MmGmV-06-PA and MmGmV-07-PA) and Gemykibivirus (MmGmV-01-PA, MmGmV-02-PA, MmGmV-03-PA, MmGmV-05-PA, and MmGmV-09-PA). At the species level, pairwise comparisons based on complete nucleotide sequences indicated the potential existence of three novel species. In summary, our study significantly contributes to an enhanced understanding of the diversity of Genomoviridae within bat samples, shedding light on previously undiscovered viral entities and their potential ecological implications. Full article

Bats are widely distributed in Brazil, including the Amazon region, and their association with viral pathogens is well-known. This work aimed to evaluate the metavirome in samples of Molossus sp. bats captured in the Brazilian Amazon from 2019 to 2021. Lung samples from 58 bats were divided into 13 pools for RNA isolation and sequencing followed by bioinformatic analysis. The Retroviridae family showed the highest abundance of viral reads. Although no complete genome could be recovered, the Paramyxoviridae and Dicistroviridae families showed the formation of contigs with satisfactory identity and size characteristics for further analysis. One contig of the Paramyxoviridae family was characterized as belonging to the genus Morbillivirus, being grouped most closely phylogenetically to Porcine morbillivirus. The contig related to the Dicistroviridae family was identified within the Cripavirus genus, with 94%, 91%, and 42% amino acid identity with Culex dicistrovirus 2, Rhopalosiphum padi, and Aphid lethal paralysis, respectively. The presence of viruses in bats needs constant updating since the study was able to identify viral sequences related to families or genera still poorly described in the literature in association with bats. Full article

The Totiviridae family of viruses has a unique genome consisting of double-stranded RNA with two open reading frames that encode the capsid protein (Cap) and the RNA-dependent RNA polymerase (RdRpol). Most virions in this family are isometric in shape, approximately 40 nm in diameter, and lack an envelope. There are five genera within this family, including Totivirus, Victorivirus, Giardiavirus, Leishmaniavirus, and Trichomonasvirus. While Totivirus and Victorivirus primarily infect fungi, Giardiavirus, Leishmaniavirus, and Trichomonasvirus infect diverse hosts, including protists, insects, and vertebrates. Recently, new totivirus-like species have been discovered in fish and plant hosts, and through metagenomic analysis, a novel totivirus-like virus (named Tianjin totivirus) has been isolated from bat guano. Interestingly, Tianjin totivirus causes cytopathic effects in insect cells but cannot grow in mammalian cells, suggesting that it infects insects consumed by insectivorous bats. In this study, we used next-generation sequencing and identified totivirus-like viruses in liver tissue from Molossus molossus bats in the Amazon region of Brazil. Comparative phylogenetic analysis based on the RNA-dependent RNA polymerase region revealed that the viruses identified in Molossus bats belong to two distinct phylogenetic clades, possibly comprising different genera within the Totiviridae family. Notably, the mean similarity between the Tianjin totivirus and the totiviruses identified in Molossus bats is less than 18%. These findings suggest that the diversity of totiviruses in bats is more extensive than previously recognized and highlight the potential for bats to serve as reservoirs for novel toti-like viruses. Full article

Chaphamaparvovirus (CHPV) is a recently characterized genus of the Parvoviridae family whose members can infect different hosts, including bats, which constitute the second most diverse order of mammals and are described worldwide as important transmitters of zoonotic diseases. In this study, we identified a new CHPV in bat samples from the municipality of Santarém (Pará state, North Brazil). A total of 18 Molossus molossus bats were analyzed using viral metagenomics. In five animals, we identified CHPVs. These CHPV sequences presented the genome with a size ranging from 3797 to 4284 bp. Phylogenetic analysis-based nucleotide and amino acid sequences of the VP1 and NS1 regions showed that all CHPV sequences are monophyletic. They are also closely related to CHPV sequences previously identified in bats in southern and southeast Brazil. According to the International Committee on Taxonomy of Viruses (ICTV) classification criteria for this species (the CHPV NS1 gene region must have 85% identity to be classified in the same species), our sequences are likely a new specie within the genus Chaphamaparvovirus, since they have less than 80% identity with other CHPV described earlier in bats. We also make some phylogenetic considerations about the interaction between CHPV and their host. We suggest a high level of specificity of CPHV and its hosts. Thus, the findings contribute to improving information about the viral diversity of parvoviruses and show the importance of better investigating bats, considering that they harbor a variety of viruses that may favor zoonotic events. Full article

Bats are natural reservoirs of a variety of zoonotic viruses, many of which cause severe human diseases. Characterizing viruses of bats inhabiting different geographical regions is important for understanding their viral diversity and for detecting viral spillovers between animal species. Herein, the diversity of DNA viruses of five arthropodophagous bat species from Argentina was investigated using metagenomics. Fecal samples of 29 individuals from five species (Tadarida brasiliensis, Molossus molossus, Eumops bonariensis, Eumops patagonicus, and Eptesicus diminutus) living at two different geographical locations, were investigated. Enriched viral DNA was sequenced using Illumina MiSeq, and the reads were trimmed and filtered using several bioinformatic approaches. The resulting nucleotide sequences were subjected to viral taxonomic classification. In total, 4,520,370 read pairs were sequestered by sequencing, and 21.1% of them mapped to viral taxa. Circoviridae and Genomoviridae were the most prevalent among vertebrate viral families in all bat species included in this study. Samples from the T. brasiliensis colony exhibited lower viral diversity than samples from other species of New World bats. We characterized 35 complete genome sequences of novel viruses. These findings provide new insights into the global diversity of bat viruses in poorly studied species, contributing to prevention of emerging zoonotic diseases and to conservation policies for endangered species. Full article

Leptospirosis is a globally distributed zoonotic disease caused by pathogenic bacteria of the genus Leptospira. This zoonotic disease affects humans, domestic animals and wild animals. Colombia is considered an endemic country for leptospirosis; Antioquia is the second department in Colombia, with the highest number of reported leptospirosis cases. Currently, many studies report bats as reservoirs of Leptospira spp. but the prevalence in these mammals is unknown. The goal of this study was to better understand the role of bats as reservoir hosts of Leptospira species and to evaluate the genetic diversity of circulating Leptospira species in Antioquia-Colombia. We captured 206 bats in the municipalities of Chigorodó (43 bats), Carepa (43 bats), Apartadó (39 bats), Turbo (40 bats), and Necoclí (41 bats) in the Urabá region (Antioquia-Colombia). Twenty bats tested positive for Leptospira spp. infection (20/206—9.70%) and the species of infected bats were Carollia perspicillata, Dermanura rava, Glossophaga soricina, Molossus molossus, Artibeus planirostris, and Uroderma convexum. These species have different feeding strategies such as frugivorous, insectivores, and nectarivores. The infecting Leptospira species identified were Leptospira borgpetersenii (3/20–15%), Leptospira alexanderi (2/20–10%), Leptospira noguchii (6/20–30%), Leptospira interrogans (3/20–15%), and Leptospira kirschneri (6/20–30%). Our results showed the importance of bats in the epidemiology, ecology, and evolution of Leptospira in this host-pathogen association. This is the first step in deciphering the role played by bats in the epidemiology of human leptospirosis in the endemic region of Urabá (Antioquia-Colombia). Full article

Chronic wounds are a major health problem that cause millions of dollars in expenses every year. Among all the treatments used, active wound treatments such as enzymatic treatments represent a cheaper and specific option with a fast growth category in the market. In particular, bacterial and plant proteases have been employed due to their homology to human proteases, which drive the normal wound healing process. However, the use of these proteases has demonstrated results with low reproducibility. Therefore, alternative sources of proteases such as snake venom have been proposed. Here, we performed a functional mining of proteases from rattlesnakes (Crotalus ornatus, C. molossus nigrescens, C. scutulatus, and C. atrox) due to their high protease predominance and similarity to native proteases. To characterize Crotalus spp. Proteases, we performed different protease assays to measure and confirm the presence of metalloproteases and serine proteases, such as the universal protease assay and zymography, using several substrates such as gelatin, casein, hemoglobin, L-TAME, fibrinogen, and fibrin. We found that all our venom extracts degraded casein, gelatin, L-TAME, fibrinogen, and fibrin, but not hemoglobin. Crotalus ornatus and C. m. nigrescens extracts were the most proteolytic venoms among the samples. Particularly, C. ornatus predominantly possessed low molecular weight proteases (P-I metalloproteases). Our results demonstrated the presence of metalloproteases capable of degrading gelatin (a collagen derivative) and fibrin clots, whereas serine proteases were capable of degrading fibrinogen-generating fibrin clots, mimicking thrombin activity. Moreover, we demonstrated that Crotalus spp. are a valuable source of proteases that can aid chronic wound-healing treatments. Full article

Snakebite envenoming is a serious medical problem in different areas of the world. In Latin America, the major prevalence is due to snakes of the family Viperidae, where rattlesnakes (Crotalus) are included. They produce hemotoxic venom which causes bleeding, tissue degradation and necrosis. Each venom has several enzymatic activities, producing different effects in the envenoming, doing its clinical effects difficult to study. Comparison between venom molecules is also difficult when different techniques are used, and therefore, their identification/characterization using the same methodology is necessary. In this work, a general biochemical characterization in snake venom of serine proteases (SVSP), phospholipases A₂ (PLA₂), metalloproteases (SVMP) and hyaluronidases (SVH) of Crotalus aquilus (Ca), Crotalus polystictus (Cp) and Crotalus molossus nigrescens (Cmn) was done. Differences in protein pattern, enzyme content and enzymatic activities were observed. All the venoms showed high PLA₂ activity, high molecular weight SVSP, and a wide variety of SVMP and SVH forms. Ca and Cp showed the highest enzymatic activities of SVMP and SVSP trypsin-like and chymotrypsin-like, whereas Cmn showed the highest SVH and similar PLA₂ activity with Ca. All the venoms showed peptides with similar molecular weight to crotamine-like myotoxins. No previous biochemical characterization of C. aquilus has been reported and there are no previous analyses that include these four protein families in these Crotalus venoms. Full article

Ontogenetic changes in venom composition have important ecological implications due the relevance of venom in prey acquisition and defense. Additionally, intraspecific venom variation has direct medical consequences for the treatment of snakebite. However, ontogenetic changes are not well documented in most species. The Mexican Black-tailed Rattlesnake (Crotalus molossus nigrescens) is large-bodied and broadly distributed in Mexico. To document venom variation and test for ontogenetic changes in venom composition, we obtained venom samples from twenty-seven C. m. nigrescens with different total body lengths (TBL) from eight states in Mexico. The primary components in the venom were detected by reverse-phase HPLC, western blot, and mass spectrometry. In addition, we evaluated the biochemical (proteolytic, coagulant and fibrinogenolytic activities) and biological (LD₅₀ and hemorrhagic activity) activities of the venoms. Finally, we tested for recognition and neutralization of Mexican antivenoms against venoms of juvenile and adult snakes. We detected clear ontogenetic venom variation in C. m. nigrescens. Venoms from younger snakes contained more crotamine-like myotoxins and snake venom serine proteinases than venoms from older snakes; however, an increase of snake venom metalloproteinases was detected in venoms of larger snakes. Venoms from juvenile snakes were, in general, more toxic and procoagulant than venoms from adults; however, adult venoms were more proteolytic. Most of the venoms analyzed were hemorrhagic. Importantly, Mexican antivenoms had difficulties recognizing low molecular mass proteins (<12 kDa) of venoms from both juvenile and adult snakes. The antivenoms did not neutralize the crotamine effect caused by the venom of juveniles. Thus, we suggest that Mexican antivenoms would have difficulty neutralizing some human envenomations and, therefore, it may be necessary improve the immunization mixture in Mexican antivenoms to account for low molecular mass proteins, like myotoxins. Full article

Bats are natural reservoirs of coronaviruses and other viruses with zoonotic potential. Florida has indigenous non-migratory populations of Brazilian free-tailed bats (Tadarida brasiliensis) that mostly roost in colonies in artificial structures. Unlike their counterparts in Brazil and Mexico, the viruses harbored by the Florida bats have been underexplored. We report the detection of an alphacoronavirus RNA-dependent RNA polymerase (RdRp) gene sequence in the feces of two of 19 different T. brasiliensis that were capture/release bats that had been evaluated for overall health. The RdRp sequence is similar but not identical to previously detected sequences in the feces of two different species of bats (T. brasiliensis and Molossus molossus) in Brazil. In common with the experience of others doing similar work, attempts to isolate the virus in cell cultures were unsuccessful. We surmise that this and highly related alphacoronavirus are carried by Brazilian free-tailed bats living in a wide eco-spatial region. As various coronaviruses (CoVs) that affect humans emerged from bats, our study raises the question whether CoVs such as the one detected in our work are yet-to-be-detected pathogens of humans and animals other than bats. Full article