Applied genomics for identification of virulent biothreats and for disease outbreak surveillance

Fortifying our preparedness to cope with biological threats by identifying and targeting virulence factors may be a preventative strategy for curtailing infectious disease outbreak. Virulence factors evoke successful pathogenic invasion, and the science and technology of genomics offers a way of identifying them, their agents and evolutionary ancestor. Genomics offers the possibility of deciphering if the release of a pathogen was intentional or natural by observing sequence and annotated data of the causative agent, and evidence of genetic engineering such as cloned vectors at restriction sites. However, to leverage and maximise the application of genomics to strengthen global interception system for real-time biothreat diagnostics, a complete genomic library of pathogenic and non-pathogenic agents will create a robust reference assembly that can be used to screen, characterise, track and trace new and existing strains. Encouraging ethical research sequencing pathogens found in animals and the environment, as well as creating a global space for collaboration will lead to effective global regulation and biosurveillance.

Complete Genomic Sequencing of Canine Distemper Virus With Nanopore Technology During an Epizootic Event

Canine distemper virus (CDV) endangers a wide range of wild animal populations and can cross species barriers, representing a significant conservational and animal health risk around the globe. During spring to autumn 2021, according to our current estimates a minimum of 50 wild live red foxes (Vulpes vulpes) died of CDV in Hungary, with CDV lesions. Oral, nasal and rectal swab samples were RT-PCR screened for Canine Distemper Virus from red fox carcasses. To investigate in more detail the origins of these CDV strains, 19 complete genomes were sequenced with a pan-genotype CDV-specific amplicon-based sequencing method developed by our laboratory and optimized for Oxford Nanopore Technologies platform. Phylogenetic analysis of the complete genomic sequences and separately the hemagglutinin gene sequences revealed the role of the Europe lineage of CDV as a causative agent for the current epizootic. Here we highlight the growing importance of fast developing rapid sequencing technologies to aid rapid response activities during epidemics or epizootic events. We also emphasize the urgent need for improved surveillance of CDV, considering the epizootic capability of enzootic strains as reported in the current study. For such future efforts, we provide a novel NGS protocol, which facilitates future genomic surveillance studies.

Occurrence of NDM-1, VIM-1, and OXA-10 Co-Producing Providencia rettgeri Clinical Isolate in China

Providencia rettgeri is a nosocomial pathogen associated with urinary tract infections related to hospital-acquired Infections. In recent years, P. rettgeri clinical strains producing New Delhi Metallo-β-lactamase (NDM) and other β-lactamase which reduce the efficiency of antimicrobial therapy have been reported. However, there are few reports of P. rettgeri co-producing two metallo-β-lactamases in one isolate. Here, we first reported a P. rettgeri strain (P138) co-harboring blaNDM-1, blaVIM-1, and blaOXA-10. The specie were identified using MALDI-TOF MS. The results of antimicrobial susceptibility testing by broth microdilution method indicated that P. rettgeri P138 was resistant to meropenem (MIC = 64μg/ml), imipenem (MIC = 64μg/ml), and aztreonam (MIC = 32μg/ml). Conjugation experiments revealed that the blaNDM-1-carrying plasmid was transferrable. The carbapenemase genes were detected using PCR and confirmed by PCR-based sequencing. The complete genomic sequence of the P. rettgeri was identified using Illumina (Illumina, San Diego, CA, USA) short-read sequencing (150bp paired-end reads), and many common resistance genes had been identified, including blaNDM-1, blaVIM-1, blaOXA-10, aac(6’)-Il, aadA5, ant(2’’)-Ia, aadA1, aac(6’)-Ib3, aadA1, aph(3’)-Ia, aac(6’)-Ib-cr, qnrD1, qnrA1, and catA2. The blaNDM-1 gene was characterized by the following structure: IS110–TnpA–IntI1–aadB–IS91–GroEL–GroES–DsbD–PAI–ble–blaNDM-1–IS91–QnrS1–IS110. Blast comparison revealed that the blaNDM-1 gene structure shared >99% similarity with plasmid p5_SCLZS62 (99% nucleotide identity and query coverage). In summary, we isolated a P. rettgeri strain coproducing blaNDM-1, blaVIM-1, and blaOXA-10. To the best of our acknowledge, this was first reported in the world. The occurrence of the strain needs to be closely monitored.

Complete genomic profiles of 1,496 Taiwanese reveal curated medical insights

Background Taiwan Biobank (TWB) project has built a nationwide database to facilitate the basic and clinical collaboration within the island and internationally, which is one of the valuable public datasets of the East Asian population. This study provided comprehensive genomic medicine findings from 1,496 WGS data from TWB. Methods We reanalyzed 1,496 Illumina-based whole genome sequences (WGS) of Taiwanese participants with at least 30X depth of coverage by Sentieon DNAscope, a precisionFDA challenge winner method. All single nucleotide variants (SNV) and small insertions/deletions 1 (Indel) have been jointly called and recalibrated as one cohort dataset. Multiple practicing clinicians have reviewed clinically significant variants. Results We found that each Taiwanese has 6,870.7 globally novel variants and classified all genomic positions according to the recalibrated sequence qualities. The variant quality score helps distinguish actual genetic variants among the technical false-positive variants, making the accurate variant minor allele frequency (MAF). All variant annotation information can be browsed at TaiwanGenomes (https://genomes.tw). We detected 54 PharmGKB-reported Cytochrome P450 (CYP) genes haplotype-drug pairs with MAF over 10% in the TWB cohort and 39.8% (439/1103) Taiwanese harbored at least one PharmGKB-reported human leukocyte antigen (HLA) risk allele. We also identified 23 variants located at ACMG secondary finding V3 gene list from 25 participants, indicating 1.67% of the population is harboring at least one medical actionable variant. For carrier status of all known pathogenic variants, we estimated one in 22 couples (4.52%) would be under the risk of having offspring with at least one pathogenic variant, which is in line with Japanese (JPN) and Singaporean (SGN) populations. We also detected 6.88% and 2.02% of carrier rates for alpha thalassemia and spinal muscular atrophy (SMA) for copy number pathogenic variants, respectively. Conclusion As WGS has become affordable for everyone, a person only needs to test once for a lifetime; comprehensive WGS data reanalysis of the genomic profile will have a significant clinical impact. Our study highlights the overall picture of a complete genomic profile with medical information for a population and individuals.

Characterization of Differentially Expressed Genes under Salt Stress in Olive

Climate change, currently taking place worldwide and also in the Mediterranean area, is leading to a reduction in water availability and to groundwater salinization. Olive represents one of the most efficient tree crops to face these scenarios, thanks to its natural ability to tolerate moderate salinity and drought. In the present work, four olive cultivars (Koroneiki, Picual, Royal de Cazorla and Fadak86) were exposed to high salt stress conditions (200 mM of NaCl) in greenhouse, in order to evaluate their tolerance level and to identify key genes involved in salt stress response. Molecular and physiological parameters, as well as plant growth and leaves’ ions Na+ and K+ content were measured. Results of the physiological measurements showed Royal de Cazorla as the most tolerant cultivar, and Fadak86 and Picual as the most susceptible ones. Ten candidate genes were analyzed and their complete genomic, CDS and protein sequences were identified. The expression analysis of their transcripts through reverse transcriptase quantitative PCR (RT-qPCR) demonstrated that only OeNHX7, OeP5CS, OeRD19A and OePetD were upregulated in tolerant cultivars, thus suggesting their key role in the activation of a salt tolerance mechanism.

Diterpene Resin Acids and Olefins in Calabrian Pine (Pinus nigra subsp. laricio (Poiret) Maire) Oleoresin: GC-MS Profiling of Major Diterpenoids in Different Plant Organs, Molecular Identification and Expression Analysis of Diterpene Synthase Genes

A quali-quantitative analysis of diterpenoid composition in tissues obtained from different organs of Pinus nigra subsp. laricio (Poiret) Maire (Calabrian pine) was carried out. Diterpene resin acids were the most abundant diterpenoids across all the examined tissues. The same nine diterpene resin acids were always found, with the abietane type prevailing on the pimarane type, although their quantitative distribution was found to be remarkably tissue-specific. The scrutiny of the available literature revealed species specificity as well. A phylogeny-based approach allowed us to isolate four cDNAs coding for diterpene synthases in Calabrian pine, each of which belonging to one of the four groups into which the d3 clade of the plants’ terpene synthases family can be divided. The deduced amino acid sequences allowed predicting that both monofunctional and bifunctional diterpene synthases are involved in the biosynthesis of diterpene resin acids in Calabrian pine. Transcript profiling revealed differential expression across the different tissues and was found to be consistent with the corresponding diterpenoid profiles. The isolation of the complete genomic sequences and the determination of their exon/intron structures allowed us to place the diterpene synthase genes from Calabrian pine on the background of current ideas on the functional evolution of diterpene synthases in Gymnosperms.

Comparison of gut viral communities in diarrhoea and healthy dairy calves

Calf diarrhoea has been a major cause of economic losses in the global dairy industry. Many factors, including multiple pathogen infections, can directly or indirectly cause calf diarrhoea. This study compared the faecal virome between 15 healthy calves and 15 calves with diarrhoea. Significantly lower diversity of viruses was found in samples from animals with diarrhoea than those in the healthy ones, and this feature may also be related to the age of the calves. Viruses belonging to the families Astroviridae and Caliciviridae that may cause diarrhoea in dairy calves have been characterized, which revealed that reads of caliciviruses and astroviruses in diarrhoea calves were much higher than those in healthy calves. Five complete genomic sequences closely related to Smacoviridae have been identified, which may participate in the regulation of the gut virus community ecology of healthy hosts together with bacteriophages. This research provides a theoretical basis for further understanding of known or potential enteric pathogens related to calf diarrhoea.

Phylogenetics and evolution of potato virus V: another potyvirus that originated in the Andes

Potato virus V (PVV) causes a disease of potato (Solanum tubersosum) in South and Central America, Europe and the Middle East. We report here the complete genomic sequences of 42 new PVV isolates from the potato’s Andean domestication centre in Peru, and of eight historical or recent isolates from Europe. When the principal open reading frames (ORFs) of these genomic sequences together with those of nine previously published genomic sequences were analysed, only two from Peru and one from Iran were found to be recombinant. The phylogeny of the 56 non-recombinant ORF sequences showed that the PVV population has two major phylogroups, one of which forms three minor phylogroups (A1-A3) of isolates, all of which are only found in the Andean region of South America (Peru and Colombia), and the other forms two minor phylogroups, a basal one of Andean isolates (A4) that is paraphyletic to a crown cluster containing all the isolates found outside South America (World). This suggests that PVV originated in the Andean region with only one minor phylogroup spreading elsewhere in the world. In minor phylogroups A3 and A4, there were subclades on long branches containing isolates from S. phureja evolving more rapidly than the others, and these interfered with dating calculations. Although no temporal signal was directly detected among the dated non-recombinant sequences, PVV and potato virus Y (PVY) are from the same potyvirus lineage and are ecologically similar, so “sub-tree dating” was done using a single maximum-likelihood phylogeny of PVV and PVY sequences, and PVY’s well-supported 157 CE “time to most common recent ancestor” was extrapolated to date that of PVV as 29 BCE. Thus the independent historical coincidences supporting the datings of the PVV and PVY phylogenies are the same; PVV arose at least 2,000 years ago in the Andes, and was taken to Europe during the Columbian Exchange, where it diversified around 1853 CE soon after the European potato late blight pandemic. PVV is likely to be more widespread than currently realised, and of biosecurity relevance for world regions that have not yet recorded its presence.

Screening Potential Drugs for COVID-19 Based on Bound Nuclear Norm Regularization

The novel coronavirus pneumonia COVID-19 infected by SARS-CoV-2 has attracted worldwide attention. It is urgent to find effective therapeutic strategies for stopping COVID-19. In this study, a Bounded Nuclear Norm Regularization (BNNR) method is developed to predict anti-SARS-CoV-2 drug candidates. First, three virus-drug association datasets are compiled. Second, a heterogeneous virus-drug network is constructed. Third, complete genomic sequences and Gaussian association profiles are integrated to compute virus similarities; chemical structures and Gaussian association profiles are integrated to calculate drug similarities. Fourth, a BNNR model based on kernel similarity (VDA-GBNNR) is proposed to predict possible anti-SARS-CoV-2 drugs. VDA-GBNNR is compared with four existing advanced methods under fivefold cross-validation. The results show that VDA-GBNNR computes better AUCs of 0.8965, 0.8562, and 0.8803 on the three datasets, respectively. There are 6 anti-SARS-CoV-2 drugs overlapping in any two datasets, that is, remdesivir, favipiravir, ribavirin, mycophenolic acid, niclosamide, and mizoribine. Molecular dockings are conducted for the 6 small molecules and the junction of SARS-CoV-2 spike protein and human angiotensin-converting enzyme 2. In particular, niclosamide and mizoribine show higher binding energy of −8.06 and −7.06 kcal/mol with the junction, respectively. G496 and K353 may be potential key residues between anti-SARS-CoV-2 drugs and the interface junction. We hope that the predicted results can contribute to the treatment of COVID-19.