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Papillomaviruses (PVs) are naked icosahedral viruses with circular double-stranded (ds) DNA genomes. They are quite stable in the environment. PVs have a strict tropism for epithelial cells and their replication induces benign hyperplasia of the skin to form common warts. Productive infection of PVs requires differentiation of keratinocytes thus these viruses cannot productively infect transformed cells. PVs are quite host specific and cross-species transmission is very rare. Over 100 types of human PVs (HPVs) have been identified. Infection by a small set of high-risk HPVs can lead to development of anogenital cancers. Vaccines that target high-risk HPVs are proving useful in decreasing the incidence of cervical cancer.

Ten species of the louse genusMyrsideabelonging to the “serini-species-group” have been reviewed. A redescription ofMyrsidea quadrifasciata(Piaget, 1880), the earliest described and valid species of this species complex, is given and a neotype for this species is designated. Nine new junior synonymies ofM. quadrifasciataare proposed and discussed. The new synonyms and their respective type hosts are:Myrsidea anoxanthiPrice and Dalgleish, 2007 fromLoxipasser anoxanthus(Gosse, 1847),Myrsidea argentina(Kellogg, 1906) fromSpinus magellanicus(Vieillot, 1805),Myrsidea balatiMacháček, 1977 fromPasser montanus(Linnaeus, 1758),Myrsidea darwiniPalma and Price, 2010 fromGeospiza fuliginosaGould, 1837,Myrsidea major(Piaget, 1880) fromPlectrophenax nivalis(Linnaeus, 1758),Myrsidea serini(Séguy, 1944) fromSerinus serinus(Linnaeus, 1766),Myrsidea queleaeTendeiro, 1964 fromQuelea quelea lathami(Smith, A., 1836),Myrsidea textorisKlockenhoff, 1984 fromPloceus cucullatus cucullatus(Müller, 1776), andMyrsidea viduaeTendeiro, 1993 fromVidua macroura(Pallas, 1764). Intraspecific morphometric variability, relative genetic divergence (based on a 379 bp portion of the mitochondrialCOIgene and a 347 bp portion of the nuclearEF-1αgene), geographical distribution, and host associations, including 8 new host records for these lice, are discussed. Taking into consideration these parameters we suggest that the only way to deal with these taxa is to follow concept of subspecies with the following taxa and their geographic distributon: Palearctic Region:M. q. quadrifasciataandM. q. serini, Neotropical Region:M. q. anoxanthi,M. q. argentina,M. q. darwini, Paleotropic Region:M. q. queleae,M. q. textorisandM. q. viduae.

Aim: The present study aimed to investigate the host- specific compatibility of sandal (Santalum album) for better root proliferation and boosting the growth of tree. Methodology: Sandal (Santalum album) was grown with 8 different leguminous and non-leguminous species at early stage to evaluate its biometric growth (height and basal diameter) and physiological (chlorophyll, photosynthesis rate and transpiration rate) performance under field conditions. Results: Sandal grown with Sesbania grandiflora recorded highest biometric observations, chlorophyll, photosynthesis and transpiration rate followed by Sandal + Albizia lebbeck and sandal + Casuarina junghuhniana. The sandal grown with leguminous host showed superior growth performance than sandal grown with non-leguminous host. Interpretation: The present study recommended that Sesbania grandiflora can be grown as transit host for boosting the growth of sandal.

Brazilian peppertree, Schinus terebinthifolia Raddi (Anacardiaceae), is an ornamental shrub from South America that is invasive in Florida, California, Hawaii and Texas, USA and has become a global...

Tombusviruses have been identified in several crops, including gentian virus A (GeVA) in Japanese gentian. In this study, we isolated another tombusvirus, Sikte waterborne virus strain C1 (SWBV-C1), from Japanese gentian. Although SWBV-C1 and GeVA are not closely related, SWBV-C1, like GeVA, showed host-specific low-temperature-dependent replication in gentian and arabidopsis. The use of in vitro transcripts from full-length cDNA clones of SWBV-C1 genomic RNA as inocula confirmed these properties, indicating that the identified genomic RNA sequences encode viral factors responsible for the characteristic features of SWBV-C1.

A new ichnospecies, Caupokeras badalloi, is here erected from the Emsian (Lower Devonian) Aguion Formation of Asturias, NW Spain. It is a bioclaustration structure produced by the host-specific sym...

The host specific whale louse Cyamus boopis Lutken, 1870, commonly found on humpback whales, is reported for the first time from a stranded bottlenose dolphin Tursiops truncatus (Montagu 1821). This is the first record of C. boopis on a dolphin species, and the second record of C. boopis outside humpback whales. Cyamid unusual records mainly reflect cetacean interspecific interactions.

The environment is under siege from a variety of pollution sources. Fecal pollution is especially harmful as it disperses pathogenic bacteria into waterways. Unraveling origins of mixed sources of fecal bacteria is difficult and microbial source tracking (MST) in complex environments is still a daunting task. Despite the challenges, the need for answers far outweighs the difficulties experienced. Advancements in qPCR and next generation sequencing (NGS) technologies have shifted the traditional culture-based MST approaches towards culture independent technologies, where community-based MST is becoming a method of choice. Metagenomic tools may be useful to overcome some of the limitations of community-based MST methods as they can give deep insight into identifying host specific fecal markers and their association with different environments. Adoption of machine learning (ML) algorithms, along with the metagenomic based MST approaches, will also provide a statistically robust and automated platform. To compliment that, ML-based approaches provide accurate optimization of resources. With the successful application of ML based models in disease prediction, outbreak investigation and medicine prescription, it would be possible that these methods would serve as a better surrogate of traditional MST approaches in future.

Pyricularia oryzae tritici, one of the most notorious pathogens of wheat, is a major biotic threat in wheat production around the globe. A total of sixteen P. oryzae tritici isolates isolated from four major wheat blast affected districts viz., Meherpur, Chuadanga, Kustia and Jhenaidaha of Bangladesh were analyzed. Considerable morphological variations in terms of colony color, texture, surface appearance, conidial size and growth pattern were observed. Molecular characterization of the isolates was done based on the sequence information of internal transcribed spacer (ITS) regions. Phylogenetic analysis based on ITS sequences of all the isolates of this study along with 18 reference Pyricularia isolates of different countries (retrieved from NCBI) revealed that isolates belonging to same district of Bangladesh did not form same cluster in the dendrogram. Again, Bangladesh—P. oryzae tritici isolates showed close relationship with other wheat infecting reference isolates from different countries. Isolates infecting other than wheat showed host specific clustering and distantly clustered in the phylogenetic tree. Findings of this study will be helpful for better understanding of this newly evolved pathogen in Bangladesh.

Epithelial cells that contain a large number of mitochondrial DNA (mtDNA) are shed in host feces. Recently, researchers have developed mtDNA markers targeting mtDNA of specific hosts and applied them to microbial source tracking (MST) for different environmental waters. This review describes the performance, persistence in environmental waters, and correlations of host-specific mtDNA markers with fecal indicators and bacterial MST markers to assess their usefulness in MST. Furthermore, concentrations are summarized for human- and animal-specific mtDNA markers in fecal sources and water that have been reported previously. For accurate identification of pollution sources, the use of host-specific mtDNA markers in combination with other MST markers in a toolbox approach is highly recommended.

It has been hypothesized that the Neolithic transition towards an agricultural and pastoralist economy facilitated the emergence of human adapted pathogens. Here, we recovered eight Salmonella enterica subsp. enterica genomes from human skeletons of transitional foragers, pastoralists, and agro-pastoralists in western Eurasia that were up to 6,500 years old. Despite the high genetic diversity of S. enterica all ancient bacterial genomes clustered in a single previously uncharacterized branch that contains S. enterica adapted to multiple mammalian species. All ancient bacterial genomes from prehistoric (agro-)pastoralists fall within a part of this branch that also includes the human-specific S. enterica Paratyphi C, illustrating the evolution of a human pathogen over a period of five thousand years. Bacterial genomic comparisons suggest that the earlier ancient strains were not host specific, differed in pathogenic potential, and experienced convergent pseudogenization that accompanied their downstream host adaptation. These observations support the concept that the emergence of human adapted S. enterica is linked to human cultural transformations.

The hemibiotrophic oomycetes are significant threats to a wide range of Cucurbitaceae species, causing substantial losses of plant productions. Particularly, Phytophthora melonis Katsura evokes severe symptoms, thus dramatically limiting the yield in cucumber. However, the information about cucumber–P. melonis interaction is still limited. This study explored the changes in the activities of phenylalanine ammonia-lyase (PAL), peroxidase (POX), catalase (CAT), superoxide dismutase (SOD) and polyphenol oxidase (PPO) in cucumber roots of two resistant genotypes (Soheil and Ramezz), one moderately resistant genotype (Baby) and three highly susceptible genotypes (Extrem, Mini 6–23 and Yalda), over the time courses of 7, 14 and 21 days after inoculation (DAI). The results indicated that the activities of defense-related enzymes differed between the resistant and highly susceptible genotypes. Although the defense-related enzymatic activities were elevated sharply in the resistant and moderately resistant genotypes after inoculation, no significant correlations were present between the activity trends of PPO, SOD and CAT and resistance characteristics. Moreover, no significant changes in enzyme activities were found in the control plants, non-inoculated plants of the six genotypes during the testing period. Altogether, the resistance of cucumber to P. melonis is related to POX and PAL activities, but does not show relationship with PPO, SOD and CAT activities. Studying the physiological metabolic pathways of POX and PAL appears to be an important direction in research to elucidate the resistance to P. melonis in cucumber genotypes.

International audience; Mucosal surfaces in contact with the environment host specific microbiota. The intestinal tract harbours the most abundant and diverse bacterial and viral populations interacting with each other as well as with the host. Viruses of the microbiota are important components of this ecosystem, as shown by viral alterations associated with various pathologies. However, practical and ethical constraints limit functional studies of the virome in humans, making animal models invaluable experimental tools to understand its impact on intestinal physiology. In this review, we present the recent advances in the study of virome in animal models. We focus on the strategies used to characterise viral changes in disease models and approaches to modulate the microbiota using viruses. In reviewing the interplay between viruses, bacteria, and the animal host, we highlight the potential and limitations of these models in elucidating the role of the virome in determining human health and disease.

Background. Influenza A viruses (IAV) exhibit vast genetic mutability and have great zoonotic potential to infect avian and mammalian hosts and are known to be responsible for a number of pandemics. A key computational issue in influenza prevention and control is the identification of molecular signatures with cross-species transmission potential. We propose an adjusted entropy-based host-specific signature identification method that uses a similarity coefficient to incorporate the amino acid substitution information and improve the identification performance.Results. Validation with a set of H5N1 PB2 sequences from 1996 to 2006 results in adjusted entropy having a 40% false negative discovery rate compared to an 80% false negative rate using unadjusted entropy. Simulations across a range of phenotypic divergence levels show a false negative rate of no higher than 10% while unadjusted entropy ranged from 9% to 100%. In addition, under all levels of divergence adjusted entropy never had a false positive rate higher than 9%. Adjusted entropy also identifies important mutations in H1N1pdm PB2 previously identified in the literature that explain changes in divergence between 2008 and 2009 which unadjusted entropy could not identify.Conclusions. Based on these results, adjusted entropy provides a reliable and widely applicable host signature identification approach useful for IAV monitoring and vaccine development.

Biological communities within living organisms are structured by their host’s traits. How host traits affect biodiversity and community composition is poorly explored for some associations, such as arthropods within fungal fruit bodies. Using DNA metabarcoding, we revealed the arthropod communities in living fruit bodies of eleven wood-decay fungi from boreal forests and investigated how they were affected by different fungal traits. Arthropod diversity was higher in fruit bodies with a larger surface area-to-volume ratio, suggesting that colonisation is crucial to maintain arthropod populations. Diversity was not higher in long-lived fruit bodies, most likely because these fungi invest in physical or chemical defences against arthropods. Arthropod community composition was structured by all measured host traits, namely fruit body size, thickness, surface area, morphology and toughness. Notably, we identified a community gradient where soft and short-lived fruit bodies harboured more true flies, while tougher and long-lived fruit bodies had more oribatid mites and beetles, which might reflect different development times of the arthropods. Ultimately, close to 75% of the arthropods were specific to one or two fungal hosts. Besides revealing surprisingly diverse and host-specific arthropod communities within fungal fruit bodies, our study provided insight on how host traits structure communities.

The resistance mechanisms evolved by insects to overcome host-plant allelochemicals are a key consideration in pest management. Camphor oil (EO) and its main component (i.e., D-camphor) form a specific terpenoid-defensive system in camphor trees, Cinnamomum camphora. However, an emerging insect pest, Pagiophloeus tsushimanus, has recently caused serious damage to this intractable plant species and is largely elusive. Here, we used feeding bioassays and RNA-seq to investigate the mechanism underlying the resistance of the beetle to host-specific terpenoid defences. First, a hormetic response in both larval weight and developmental time, which is a highly generalized dose-response phenomenon in toxicology but occurs infrequently in the context of insect-plant interactions, was observed in terpenoid-feeding individuals. Then, comparative transcriptome analysis between terpenoid-feeding and control groups indicated that both CYP450-mediated metabolic resistance and CP-mediated cuticular resistance were jointly employed to cope with terpenoid-induced stress. In addition, a small portion of genes involved in the glucose transport pathway were upregulated at the low D-camphor dose, suggesting that an extra intake of glucose used for larval growth may contribute to a hormetic response. These findings suggested that the dual terpenoid resistance mechanisms in this specialist are an essential precondition for the hormetic response in larval growth, ultimately contributing to the widespread successful colonization of host camphor trees. Overall, our study will open new avenues for understanding insect-plant coevolutionary adaptation and developing durable pest control strategies.

Since the increasing prevalence of herbicide-resistant weeds and herbicide bans, the use of biological controls with mycoherbicides become an innovative approach of weed control. In this study, we verified the pathogenicity of Phoma multirostrata TBRC 12769 against the common weed in Thailand, tridax daisy (Tridax procumbens), with its mechanism of infection unveiled by fluorescence microscopy. P. multirostrata directly penetrated through epidermal cells, stomata, and trichomes at 48 h post-inoculation. The hyphae also propagated in the lumen of the trichome, enabling the fungus to grow subcuticular to neighboring weed tissues at the bases of leaf trichomes. The necrotic pattern emerged around the trichome. During necrosis, unicellular chlamydospores were also detected inside the leaf trichomes, suggesting an overwintering stage under stress and nutrient-depleting conditions. Trichomes of weed leaves were found to be key infection sites for pathogenesis. Topical application of conidial suspension on T. procumbens potted plants led to 60-98% and 65 and 87% disease incidence under laboratory and greenhouse conditions, respectively, on days 15-20 post-inoculation. The 16-h dew period incubation results in a sharp increase by 37% in the pathogenicity rate. The greenhouse trials verified that the fungus is non-pathogenic to eight crops. Our LC-MS analysis indicated that norharman, a known bioherbicidal compound, and other compounds were detected in the supernatant fraction of fungal culture, of which resulted in a blight symptom on T. procumbens leaves. This study demonstrated that the P. multirostrata isolate is an effective mycoherbicide for this broadleaf weed.

Food resource access can mediate establishment success in invasive species, and generalist herbivorous insects are thought to rely on mechanisms of transcriptional plasticity to respond to dietary variation. While asexually reproducing invasives typically have low genetic variation, the twofold reproductive capacity of asexual organisms is a marked advantage for colonization. We studied host-related transcriptional acclimation in parthenogenetic, invasive, and polyphagous weevils: Naupactus cervinus and N. leucoloma. We analyzed patterns of gene expression in three gene categories that can mediate weevil-host plant interactions through identification of suitable host plants, short-term acclimation to host plant defenses, and long-term adaptation to host plant defenses and their pathogens. This approach employed comparative transcriptomic methods to investigate differentially expressed host detection, detoxification, immune defense genes, and pathway-level gene set enrichment. Our results show that weevil gene expression responses can be host plant-specific, and that elements of that response can be transgenerational. Some host plant groups, such as legumes, appear to be more taxing as they elicit a complex gene expression response which is both strong in intensity and specific in identity. However, the weevil response to taxing host plants shares many differentially expressed genes with other stressful situations, such as host plant cultivation conditions and transition to novel host, suggesting that there is an evolutionarily favorable shared gene expression regime for responding to different types of stressful situations. Modulating gene expression in the absence of other avenues for phenotypic adaptation may be an important mechanism of successful colonization for these introduced insects., Facultad de Ciencias Naturales y Museo

The spread of African swine fever (ASF) poses a grave threat to the global swine industry. Understanding transmission dynamics, such as through mechanistic modeling, is critical for designing effective control strategies. Articles were examined across multiple epidemiological and model characteristics. Model filiation was determined through creation of a neighbor-joined tree using phylogenetic software. Of 34 four articles qualifying for inclusion, four main modelling objectives were identified: estimating transmission parameters (11 studies), assessing determinants of transmission (7), examining consequences of hypothetical outbreaks (5), and assessing alternative control strategies (11). Estimated transmission parameters varied widely as did parameter assumptions between models. Uncertainties on epidemiological and ecological parameters were usually accounted for to assess the impact on the modeled infection trajectory. Almost all models are host specific, being developed for either domestic pigs or wild boar despite the fact that spillover events between domestic pigs and wild boar are evidenced to play an important role in ASF outbreaks. The development of models incorporating such transmission routes is crucial. All compared control strategies were defined a priori, and future models should be built to identify optimal contributions across many control methods. Further, control strategies were examined in competition, opposed to how they would be synergistically implemented. While comparing strategies is beneficial for identifying a rank-order efficacy of control methods, this structure does not necessarily determine the most effective combination of all available strategies. In order for ASFV models to effectively support decision-making in controlling ASFV globally, these modelling limitations need to be addressed., 19 pages, 3 figures, 4 tables. Accepted to Preventive Veterinary Medicine. Revised from previous preprint to include models published through Dec 2020

Fungal diseases cause considerable damage to the economically important crops worldwide thus posing continuous threat to global food security. Management of these diseases is normally done via utilization of chemicals that have severe negative impact upon human health and surrounding ecosystems. Finding eco-friendly alternatives has led the researchers to focus towards biological control of fungal diseases through biocontrol agents such as antagonistic fungi (AF) and other microorganisms. AF include various genera of fungi that cure the fungal diseases on plants effectively. Furthermore, they play a regulatory role in various plant physiological pathways and interactions. AF are highly host specific having negligible effects on non-target organisms and have fast mass production capability. However, understanding the mechanisms of the effects of AF on plant diseases is a prerequisite for their effective utilization as biocontrol agent. Trichoderma is one of the most important fungal genera known for its antagonistic activity against disease causing fungal pathogens. Therefore, in this review, we have focused upon Trichoderma-mediated fungal diseases management via illustrating its taxonomy, important strains, biodiversity and mode of action. Furthermore, we have assessed the criteria to be followed for selection of AF and the factors influencing their efficiency. Finally, we evaluated the advantages and limitations of Trichoderma as AF. We conclude that effective AF utilization against fungal pathogens can serve as a safe strategy for our Planet.

Isolating single phages using plaque assays is a laborious and time-consuming process. Whether single isolated phages are the most lyse-effective, the most abundant in viromes, or those with the highest ability to make plaques in solid media is not well known. With the increasing accessibility of high-throughput sequencing, metaviromics is often used to describe viruses in environmental samples. By extracting and sequencing metaviromes from organic waste with and without exposure to a host-of-interest, we show a host-related phage community’s shift, as well as identify the most enriched phages. Moreover, we isolated plaque-forming single phages using the same virome–host matrix to observe how enrichments in liquid media correspond to the metaviromic data. In this study, we observed a significant shift (p = 0.015) of the 47 identified putative Pseudomonas phages with a minimum twofold change above zero in read abundance when adding a Pseudomonas&nbsp, syringae DC3000 host. Surprisingly, it appears that only two out of five plaque-forming phages from the same organic waste sample, targeting the Pseudomonas strain, were highly abundant in the metavirome, while the other three were almost absent despite host exposure. Lastly, our sequencing results highlight how long reads from Oxford Nanopore elevates the assembly quality of metaviromes, compared to short reads alone.

Tan spot, caused by Pyrenophora tritici-repentis (Ptr), is an important disease of wheat worldwide, and an emerging issue in New Zealand. The pathogen produces host-specific toxins which interact with the wheat host sensitivity loci. Identification of the prevalence of the toxin encoding genes in the local population, and the susceptibility of commonly grown wheat cultivars to Ptr will aid selection of wheat cultivars to reduce disease risk. Twelve single spore isolates collected from wheat-growing areas of the South Island of New Zealand representing the P. tritici-repentis population were characterised for the Ptr ToxA and ToxB genes, ToxA and ToxB, respectively, using two gene specific primers. The susceptibility of 10 wheat cultivars to P. tritici-repentis was determined in a glasshouse experiment by inoculating young plants with a mixed-isolate spore inoculum. All 12 New Zealand P. tritici-repentis isolates were positive for the ToxA gene but none were positive for the ToxB gene. Tan spot lesions developed on all inoculated 10 wheat cultivars, with cultivars ‘Empress’ and ‘Duchess’ being the least susceptible and ‘Discovery’, ‘Reliance’ and ‘Saracen’ the most susceptible cultivars to infection by the mixed-isolate spore inoculum used. The results indicated that the cultivars ‘Empress’ and ‘Duchess’ may possess a level of tolerance to P. tritici-repentis and would, therefore, be recommended for cultivation in regions with high tan spot incidence.

A recommendation of: Fanny Cavigliasso, Hugo Mathe-Hubert, Jean-Luc Gatti, Dominique Colinet, Marylene Poirie Parasitic success and venom composition evolve upon specialization of parasitoid wasps to different host species 10.1101/2020.10.24.353417

Recreational waters are primary attractions at many national and state parks where feral swine populations are established, and thus are possible hotspots for visitor exposure to feral swine contaminants. Microbial source tracking (MST) was used to determine spatial and temporal patterns of fecal contamination in Congaree National Park (CONG) in South Carolina, U.S.A., which has an established population of feral swine and is a popular destination for water-based recreation. Water samples were collected between December 2017 and June 2019 from 18 surface water sites distributed throughout CONG. Host specific MST markers included human (HF183), swine (Pig2Bac), ruminant (Rum2Bac), cow (CowM3), chicken (CL), and a marker for shiga toxin producing Escherichia coli (STEC; stx2). Water samples were also screened for culturable Escherichia coli (E. coli) as part of a citizen science program. Neither the cow nor chicken MST markers were detected during the study. The human marker was predominantly detected at boundary sites or could be attributed to upstream sources. However, several detections within CONG without concurrent detections at upstream external sites suggested occasional internal contamination from humans. The swine marker was the most frequently detected of all MST markers, and was present at sites located both internal and external to the Park. Swine MST marker concentrations ≥ 43 gene copies/mL were associated with culturable E. coli concentrations greater than the U.S. Environmental Protection Agency beach action value for recreational waters. None of the MST markers showed a strong association with detection of the pathogenic marker (stx2). Limited information about the health risk from exposure to fecal contamination from non-human sources hampers interpretation of the human health implications.

The rhizosphere fungi show a close association with the root of most plants, and significantly improve the growth of the plant. The kind of plant–microbe interaction is major contribution of fungus and especially mycorrhiza. Their mode of interaction may be direct or indirect as mediated by the host specific plant. These fungal plant associations provide the positive effect on crop plants can be show for the nutritional aspects for plant and manage by inoculation of microbial combination selected for their compatibility and mutual effect.

Klebsiella pneumoniae is emerging as an important bacterial plant pathogen in Asia region particularly in China and India. The Chinese strain of Klebsiella pneumoniae causing top rot of maize is reported to be pathogenic on mice also. The Indian strain of Klebsiella pneumoniae causing root bark necrosis and wilt in pomegranate is found non- pathogenic on Indian bird chicken, thereby indicating it to be plant host specific.

CRISPR arrays contain spacers, some of which are homologous to genome segments of viruses and other parasitic genetic elements and are employed as portion of guide RNAs to recognize and specifically inactivate the target genomes. However, the fraction of the spacers in sequenced CRISPR arrays that reliably match protospacer sequences in genomic databases is small, leaving the question of the origin(s) open for the great majority of the spacers. Here, we extend the spacer analysis by examining the distribution of partial matches (matching k-mers) between spacers and genomes of viruses infecting the given host as well as the host genomes themselves. The results indicate that most of the spacers originate from the host-specific viromes, whereas self-targeting is strongly selected against. However, we present evidence that the vast majority of the viruses comprising the viromes currently remain unknown although they are likely to be related to identified viruses., Sergey A. Shmakov et al. investigate the origin of the CRISPR spacers. They examine the distribution of partial matches between the spacers, viral genomes, and the host genomes and report that most of the spacers originate from host specific viromes. They demonstrate that most of the viruses are unknown although are likely related to known viruses.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has resulted in the current COVID-19 pandemic. Worldwide this disease has infected around 1.5 million individuals with a mortality rate ranging from 5 to 10%. It has also imposed extreme challenges on global health, economy, and social behavior. Due to the unavailability of therapeutics, several efforts are going on in the drug discovery to control the SARS-CoV-2 viral infection. The main protease (MPro) plays a critical role in viral replication and maturation, thus can serve as the primary drug target. To understand the structural evolution of MPro, we have performed phylogenetic and SSN analysis, that depicted divergence of Coronaviridae MPro in five clusters specific to viral hosts. This clustering was also corroborated with the comparison of MPro structures. Furthermore, it has been observed that backbone and binding site conformations are conserved despite variation in some of the residues. This conservation can be exploited to repurpose available viral protease inhibitors against SARS-CoV-2 MPro. In agreement with this, we performed screening of the custom-made library of ~7100 molecules including active ingredients present in the Ayurvedic anti-tussive medicines, anti-viral phytochemicals and synthetic anti-virals against SARS-CoV-2 MPro as the primary target. We identified several natural molecules that strongly binds to SARS-CoV-2 MPro among which top seven molecules are d-Viniferin, Myricitrin, Taiwanhomoflavone A, Lactucopicrin 15-oxalate, Nympholide A, Biorobin and Phyllaemblicin B. Most of the predicted lead molecules are from Vitis vinifera, also reported for anti-tussive and/or antiviral activities. These molecules also showed strong binding with other main targets RdRp and hACE-2. We anticipate that our approach for identification of multi-target-directed ligand will provide new avenues for drug discovery against SARS-CoV-2 infection.

The fungus Myriosclerotinia sulcatula is a close relative of the notorious polyphagous plant pathogens Botrytis cinerea and Sclerotinia sclerotiorum but exhibits a host range restricted to plants from the Carex genus (Cyperaceae family). To date, there are no genomic resources available for fungi in the Myriosclerotinia genus. Here, we present a chromosome-scale reference genome assembly for M. sulcatula. The assembly contains 24 contigs with a total length of 43.53 Mbp, with scaffold N50 of 2,649.7 kbp and N90 of 1,133.1 kbp. BRAKER-predicted gene models were manually curated using WebApollo, resulting in 11,275 protein-coding genes that we functionally annotated. We provide a high-quality reference genome assembly and annotation for M. sulcatula as a resource for studying evolution and pathogenicity in fungi from the Sclerotiniaceae family. file: :Users/u0129515/Sync/My_list_publication/2020/Kusch et al., 2020b.pdf:pdf ispartof: Molecular Plant-Microbe Interactions vol:33 issue:7 pages:880-883 ispartof: location:United States status: Published online

Herpesviruses are ubiquitous and can cause disease in all classes of vertebrates but also in animals of lower taxa, including molluscs. It is generally accepted that herpesviruses are primarily species specific, although a species can be infected by different herpesviruses. Species specificity is thought to result from host-virus coevolutionary processes over the long term. Even with this general concept in mind, investigators have recognized interspecies transmission of several members of the Herpesviridae family, often with fatal outcomes in non-definitive hosts—that is, animals that have no or only a limited role in virus transmission. We here summarize herpesvirus infections in wild mammals that in many cases are endangered, in both natural and captive settings. Some infections result from herpesviruses that are endemic in the species that is primarily affected, and some result from herpesviruses that cause fatal disease after infection of non-definitive hosts. We discuss the challenges of such infections in several endangered species in the absence of efficient immunization or therapeutic options.

Freshwater crayfishes serve as hosts to diverse epifaunal assemblages. We investigated epifauna on 3 native and 2 alien freshwater crayfish collected in Croatia (Europe). Our main goals wer...

Over the last years, there has been an enormous increase in the knowledge on koi herpesvirus (KHV), koi herpesvirus disease (KHVD), pathogenesis and virus variants. Different KHV lineages have clearly been identified, possible genomic changes during replication in different cell cultures at different temperatures but also in several hosts have been identified, a persistent stage of infection has been specified and it has been shown that infection with KHV is not host specific at all, but KHVD is. Additionally, it has been shown that it is possible to combat KHVD by immunization with inactivated and attenuated live vaccines using different delivery systems but also to benefit from alternative treatments with e.g. exopolysaccharids obtained from Arthrospira platensis.

Bacteriophages present alternatives to antibiotics. In the age of superbugs and antibiotic resistance, the field of medicine is trying to create new antibiotics or derivatives of the old ones to eliminate bacterial infections. Bacteriophages are specific to a certain type of bacterial species and effectively kill the bacteria of target. In order to effectively use the bacteriophages as medicine, their possible side effects should be properly analyzed and one of those includes their activities on the immune system cells. In this study, we isolated two new Escherichia coli bacteriophages and tested their effect on the activation state of the mammalian macrophages. The bacteriophages were host specific and had substantial adsorption rates on E. coli. Moreover, they were able to effectively stimulate the macrophages in the absence of a bacterial stimulant, lipopolysaccharides. This implies that these bacteriophages can be used against E. coli infections in which proper immune system activation is missing. This study is the first one to our knowledge specifically showing the immunostimulatory effect of newly isolated E. coli bacteriophages on the macrophages. It is important to determine the effect of bacteriophages on the immune system cells before their use as antibiotics.

More than a century has passed since the identification of Mycobacterium tuberculosis (Mtb) as the causative agent of tuberculosis (TB), we still are nowhere close to eradicating this deadly disease. Moreover, emergence of new drug-resistant strains has further complicated the situation, making it even more difficult to treat by conventional therapy regimens. Humans are the only reservoir for the existence and propagation of Mtb, which suggests that its latent forms will be most difficult to eradicate, till the human race lasts. Mtb has been associated with us for ages and its evolution is strictly guided to exploit its human host for survival and spread. The strategies employed by Mtb are unique and host specific, thereby making it hard to break this association without accurate understanding of this host-pathogen interaction. Metabolic pathways have always been at the heart of Mtb pathogenesis, with a continuous cross-talk between the pathogen and the host. Over the years, Mtb has mastered the art of manipulating the host machinery, along with modulating its own metabolism for survival in the hostile conditions. Here we aim to summarize the history of tuberculosis, its pathology and recent advances in basic understanding of the machinery, with eventual gape on the novel therapeutic strategies emerged in the past decade. © 2018 IUBMB Life, 70(9):917-925, 2018.

Widespread decline of whitebark and limber pines in the northern Rocky Mountains (USA) has created an imperative to understand functional diversity in their ectomycorrhizal associates. Because suilloid fungi are likely important in successful reestablishment of pines the nitrogen-related functional traits of 28 high-elevation suilloid isolates were examined. Radial growth, mass accumulation and mycelial density were measured for isolates on six different nitrogen sources. The δ15N values of suilloid sporocarps used as sources for pure cultures were compared against growth parameters to investigate a possible link between these N-related functional traits. Isolates grew poorly on nitrate and BSA and grew well on glutamine, alanyl-glutamine and ammonium phosphate, with somewhat slower growth on alanine. Isolates and species varied considerably in their growth response to different nitrogen sources. Effective use of nitrate and BSA was uncommon and associated with isolates with high inherent growth rates. Sporocarp δ15N was negatively correlated with relative growth on alanine of the corresponding isolates. Our results suggest strong similarities in N source use patterns of suilloid fungi of whitebark pine origin and those of another high-elevation five-needle stone pine, the Swiss stone pine.