scholarly journals Novel Single Hematophagous Insect RNA Detection Method Supports Its Use as Sentinels to Survey Flaviviruses Circulation

Author(s):  
Juliana Sá Teles de Oliveira Molina ◽  
Andreia Moreira dos Santos Carmo ◽  
Gabriel Lopes Pereira ◽  
Leticia Abrantes de Andrade ◽  
Felipe Trovalim Jordão ◽  
...  

Anthropogenic actions, including deforestation, disorganized urbanization, and globalization, contribute to emergence and reemergence of arboviruses worldwide, where Flavivirus is the most prevalent, and its continuous monitoring can help in preventive control strategies. Thus, the aim of this study was to detect flavivirus RNA in single hematophagous insects, which are used as sentinels. Total RNA was extracted from six Aedes aegypti stored since 2003 and from 100 Culicidae and collected through CDC trap in a public park of a Brazilian Northwest city of São Paulo State. Flavivirus was detected through RT/PCR targeting 230–250 bp of the RNA polymerase coding sequence (NS5). PCR amplicons were sequenced by Sanger method, used in comparative analysis over Basic Local Alignment Search Tool (BLAST) in GenBank, and subjected to Neighbor-Joining phylogenetic analyses. Efficiency of Flavivirus diagnosis was confirmed by detection of Dengue virus serotype 2 in Ae. aegypti. From the 100 collected insects, 19 were positive for Culex flavivirus (CxFV). NS5 partial sequence phylogenetic analysis clustered all CxFV in one branch separated from vertebrate flaviviruses, being applicable to the identification of Flavivirus species. The dipteran RNA extraction methodology described in this work supports detection of flaviviruses in single insects maintained in 80% ethanol, which can be used to constant arbovirus surveillance.

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Tinashe G. Chabikwa ◽  
Francois F. Barbier ◽  
Milos Tanurdzic ◽  
Christine A. Beveridge

AbstractAvocado (Persea americana Mill.), macadamia (Macadamia integrifolia L.) and mango (Mangifera indica L.) are important subtropical tree species grown for their edible fruits and nuts. Despite their commercial and nutritional importance, the genomic information for these species is largely lacking. Here we report the generation of avocado, macadamia and mango transcriptome assemblies from pooled leaf, stem, bud, root, floral and fruit/nut tissue. Using normalized cDNA libraries, we generated comprehensive RNA-Seq datasets from which we assembled 63420, 78871 and 82198 unigenes of avocado, macadamia and mango, respectively using a combination of de novo transcriptome assembly and redundancy reduction. These unigenes were functionally annotated using Basic Local Alignment Search Tool (BLAST) to query the Universal Protein Resource Knowledgebase (UniProtKB). A workflow encompassing RNA extraction, library preparation, transcriptome assembly, redundancy reduction, assembly validation and annotation is provided. This study provides avocado, macadamia and mango transcriptome and annotation data, which is valuable for gene discovery and gene expression profiling experiments as well as ongoing and future genome annotation and marker development applications.


Genes ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 1007 ◽  
Author(s):  
Matle ◽  
Pierneef ◽  
Mbatha ◽  
Magwedere ◽  
Madoroba

Listeria monocytogenes is a highly fatal foodborne causative agent that has been implicated in numerous outbreaks and related deaths of listeriosis in the world. In this study, six L. monocytogenes isolated from ready-to-eat (RTE) meat products were analysed using Whole Genome Sequencing (WGS) to identify virulence and resistance genes, prophage sequences, PCR-serogroups, and sequence types (STs). The WGS identified four different STs (ST1, ST121, ST204, and ST876) that belonged to serogroup 4b (lineage I) and 1/2a (lineage II). Core genome, and average nucleotide identity (ANI) phylogenetic analyses showed that the majority of strains from serogroup 4b (lineage I) clustered together. However, two isolates that belong to serogroup 1/2a (lineage II) grouped far from each other and the other strains. Examination of reference-guided scaffolds for the presence of prophages using the PHAge Search Tool Enhanced Release (PHASTER) software identified 24 diverse prophages, which were either intact or incomplete/questionable. The National Center for Biotechnology Information- Nucleotide Basic Local Alignment Search Tool (NCBI-BLASTn) revealed that Listeria monocytogenes strains in this study shared some known major virulence genes that are encoded in Listeria pathogenicity islands 1 and 3. In general, the resistance profiles for all the isolates were similar and encoded for multidrug, heavy metal, antibiotic, and sanitizer resistance genes. All the isolates in this study possessed genes that code for resistance to common food processing antiseptics such as Benzalkonium chloride.


2014 ◽  
Vol 21 (1) ◽  
pp. 33-42 ◽  
Author(s):  
Fahad M.A. Al-Hemaid ◽  
M. Ajmal Ali ◽  
Joongku Lee ◽  
Gábor Gyulai ◽  
Arun K. Pandey

The present study explored the use of internal transcribed spacers (ITS) sequences (ITS1-5.8S-ITS2) of nuclear ribosomal DNA (nrDNA) for identification of Echinops mandavillei Kit Tan, an endemic species to Saudi Arabia. The sequence similarity search using Basic Local Alignment Search Tool (BLAST) and phylogenetic analyses of the ITS sequence of E. mandavillei Kit Tan showed high level of sequence similarity (98%) with E. glaberrimus DC. (section Ritropsis). The novel primary sequence and the secondary structure of ITS2 of E. mandavillei could have a potential use for molecular genotyping.DOI: http://dx.doi.org/10.3329/bjpt.v21i1.19256Bangladesh J. Plant Taxon. 21(1): 33-42, 2014 (June)


2020 ◽  
Vol 17 (6) ◽  
pp. 397-407
Author(s):  
Maryam Jarchi ◽  
Farah Bokharaei-Salim ◽  
Maryam Esghaei ◽  
Seyed Jalal Kiani ◽  
Fatemeh Jahanbakhsh ◽  
...  

Background: The advent of resistance-associated mutations in HIV-1 is a barrier to the success of the ARTs. Objective: In this study, the abundance of HIV-1 infection in Iranian children, and also detection of the TDR in naïve HIV-1 infected pediatric (under 12 years old) were evaluated. Materials: From June 2014 to January 2019, a total of 544 consecutive treatment-naïve HIV-1- infected individuals enrolled in this study. After RNA extraction, amplification, and sequencing of the HIV-1 pol gene, the DRM and phylogenetic analysis were successfully performed on the plasma specimens of the ART-naïve HIV-1-infected-children under 12 years old. The DRMs were recognized using the Stanford HIV Drug Resistance Database. Results: Out of the 544 evaluated treatment-naïve HIV-1-infected individuals, 15 (2.8%) cases were children under 12 years old. The phylogenetic analyses of the amplified region of pol gene indicated that all of the 15 HIV-1-infected pediatric patients were infected by CRF35_AD, and a total of 13.3% (2/15) of these children were infected with HIV-1 variants with SDRMs (one child harbored two related SDRMs [D67N, V179F], and another child had three related SDRMs [M184V, T215F, and K103N]), according to the last algorithm of the WHO. No PIs-related SDRMs were observed in HIV-1-infected children. Conclusion: The current study demonstrated that a total of 13.3% of treatment-naïve HIV-1-infected Iranian pediatrics (under 12 years old) were infected with HIV-1 variants with SDRMs. Therefore, it seems that screening to recognize resistance-associated mutations before the initiation of ARTs among Iranian children is essential for favorable medication efficacy and dependable prognosis.


2019 ◽  
Vol 14 (2) ◽  
pp. 157-163
Author(s):  
Majid Hajibaba ◽  
Mohsen Sharifi ◽  
Saeid Gorgin

Background: One of the pivotal challenges in nowadays genomic research domain is the fast processing of voluminous data such as the ones engendered by high-throughput Next-Generation Sequencing technologies. On the other hand, BLAST (Basic Local Alignment Search Tool), a longestablished and renowned tool in Bioinformatics, has shown to be incredibly slow in this regard. Objective: To improve the performance of BLAST in the processing of voluminous data, we have applied a novel memory-aware technique to BLAST for faster parallel processing of voluminous data. Method: We have used a master-worker model for the processing of voluminous data alongside a memory-aware technique in which the master partitions the whole data in equal chunks, one chunk for each worker, and consequently each worker further splits and formats its allocated data chunk according to the size of its memory. Each worker searches every split data one-by-one through a list of queries. Results: We have chosen a list of queries with different lengths to run insensitive searches in a huge database called UniProtKB/TrEMBL. Our experiments show 20 percent improvement in performance when workers used our proposed memory-aware technique compared to when they were not memory aware. Comparatively, experiments show even higher performance improvement, approximately 50 percent, when we applied our memory-aware technique to mpiBLAST. Conclusion: We have shown that memory-awareness in formatting bulky database, when running BLAST, can improve performance significantly, while preventing unexpected crashes in low-memory environments. Even though distributed computing attempts to mitigate search time by partitioning and distributing database portions, our memory-aware technique alleviates negative effects of page-faults on performance.


Animals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1149
Author(s):  
Dina M. Metwally ◽  
Isra M. Al-Turaiki ◽  
Najwa Altwaijry ◽  
Samia Q. Alghamdi ◽  
Abdullah D. Alanazi

We analyzed the blood from 400 one-humped camels, Camelus dromedarius (C. dromedarius), in Riyadh and Al-Qassim, Saudi Arabia to determine if they were infected with the parasite Trypanosoma spp. Polymerase chain reaction (PCR) targeting the internal transcribed spacer 1 (ITS1) gene was used to detect the prevalence of Trypanosoma spp. in the camels. Trypanosoma evansi (T. evansi) was detected in 79 of 200 camels in Riyadh, an infection rate of 39.5%, and in 92 of 200 camels in Al-Qassim, an infection rate of 46%. Sequence and phylogenetic analyses revealed that the isolated T. evansi was closely related to the T. evansi that was detected in C. dromedarius in Egypt and the T. evansi strain B15.1 18S ribosomal RNA gene identified from buffalo in Thailand. A BLAST search revealed that the sequences are also similar to those of T. evansi from beef cattle in Thailand and to T. brucei B8/18 18S ribosomal RNA from pigs in Nigeria.


Viruses ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 615
Author(s):  
Allen Wing-Ho Chu ◽  
Cyril Chik-Yan Yip ◽  
Wan-Mui Chan ◽  
Anthony Chin-Ki Ng ◽  
Dream Lok-Sze Chan ◽  
...  

SARS-CoV-2 RT-PCR with pooled specimens has been implemented during the COVID-19 pandemic as a cost- and manpower-saving strategy for large-scale testing. However, there is a paucity of data on the efficiency of different nucleic acid extraction platforms on pooled specimens. This study compared a novel automated high-throughput liquid-based RNA extraction (LRE) platform (PHASIFYTM) with a widely used magnetic bead-based total nucleic acid extraction (MBTE) platform (NucliSENS® easyMAG®). A total of 60 pools of nasopharyngeal swab and 60 pools of posterior oropharyngeal saliva specimens, each consisting of 1 SARS-CoV-2 positive and 9 SARS-CoV-2 negative specimens, were included for the comparison. Real-time RT-PCR targeting the SARS-CoV-2 RdRp/Hel gene was performed, and GAPDH RT-PCR was used to detect RT-PCR inhibitors. No significant differences were observed in the Ct values and overall RT-PCR positive rates between LRE and MBTE platforms (92.5% (111/120] vs 90% (108/120]), but there was a slightly higher positive rate for LRE (88.3% (53/60]) than MBTE (81.7% (49/60]) among pooled saliva. The automated LRE method is comparable to a standard MBTE method for the detection of SAR-CoV-2 in pooled specimens, providing a suitable alternative automated extraction platform. Furthermore, LRE may be better suited for pooled saliva specimens due to more efficient removal of RT-PCR inhibitors.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Dimitri Boeckaerts ◽  
Michiel Stock ◽  
Bjorn Criel ◽  
Hans Gerstmans ◽  
Bernard De Baets ◽  
...  

AbstractNowadays, bacteriophages are increasingly considered as an alternative treatment for a variety of bacterial infections in cases where classical antibiotics have become ineffective. However, characterizing the host specificity of phages remains a labor- and time-intensive process. In order to alleviate this burden, we have developed a new machine-learning-based pipeline to predict bacteriophage hosts based on annotated receptor-binding protein (RBP) sequence data. We focus on predicting bacterial hosts from the ESKAPE group, Escherichia coli, Salmonella enterica and Clostridium difficile. We compare the performance of our predictive model with that of the widely used Basic Local Alignment Search Tool (BLAST). Our best-performing predictive model reaches Precision-Recall Area Under the Curve (PR-AUC) scores between 73.6 and 93.8% for different levels of sequence similarity in the collected data. Our model reaches a performance comparable to that of BLASTp when sequence similarity in the data is high and starts outperforming BLASTp when sequence similarity drops below 75%. Therefore, our machine learning methods can be especially useful in settings in which sequence similarity to other known sequences is low. Predicting the hosts of novel metagenomic RBP sequences could extend our toolbox to tune the host spectrum of phages or phage tail-like bacteriocins by swapping RBPs.


Viruses ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 393
Author(s):  
Mpho Magwalivha ◽  
Jean-Pierre Kabue Ngandu ◽  
Afsatou Ndama Traore ◽  
Natasha Potgieter

Diarrhoeal disease is considered an important cause of morbidity and mortality in developing areas, and a large contributor to the burden of disease in children younger than five years of age. This study investigated the prevalence and genogroups of human sapovirus (SV) in children ≤5 years of age in rural communities of Vhembe district, South Africa. Between 2017 and 2020, a total of 284 stool samples were collected from children suffering with diarrhoea (n = 228) and from children without diarrhoea (n = 56). RNA extraction using Boom extraction method, and screening for SV using real-time PCR were done in the lab. Positive samples were subjected to conventional RT-PCR targeting the capsid fragment. Positive sample isolates were genotyped using Sanger sequencing. Overall SV were detected in 14.1% (40/284) of the stool samples (16.7% (38/228) of diarrhoeal and 3.6% (2/56) of non-diarrhoeal samples). Significant correlation between SV positive cases and water sources was noted. Genogroup-I was identified as the most prevalent strain comprising 81.3% (13/16), followed by SV-GII 12.5% (2/16) and SV-GIV 6.2% (1/16). This study provides valuable data on prevalence of SV amongst outpatients in rural and underdeveloped communities, and highlights the necessity for further monitoring of SV circulating strains as potential emerging strains.


2020 ◽  
Vol 19 (1) ◽  
Author(s):  
Ommer Mohammed Dafalla ◽  
Mohammed Alzahrani ◽  
Ahmed Sahli ◽  
Mohammed Abdulla Al Helal ◽  
Mohammad Mohammad Alhazmi ◽  
...  

Abstract Background Artemisinin-based combination therapy (ACT) is recommended at the initial phase for treatment of Plasmodium falciparum, to reduce morbidity and mortality in all countries where malaria is endemic. Polymorphism in portions of P. falciparum gene encoding kelch (K13)-propeller domains is associated with delayed parasite clearance after ACT. Of about 124 different non-synonymous mutations, 46 have been identified in Southeast Asia (SEA), 62 in sub-Saharan Africa (SSA) and 16 in both the regions. This is the first study designed to analyse the prevalence of polymorphism in the P. falciparum k13-propeller domain in the Jazan region of southwest Saudi Arabia, where malaria is endemic. Methods One-hundred and forty P. falciparum samples were collected from Jazan region of southwest Saudi Arabia at three different times: 20 samples in 2011, 40 samples in 2016 and 80 samples in 2020 after the implementation of ACT. Plasmodium falciparum kelch13 (k13) gene DNA was extracted, amplified, sequenced, and analysed using a basic local alignment search tool (BLAST). Results This study obtained 51 non-synonymous (NS) mutations in three time groups, divided as follows: 6 single nucleotide polymorphisms (SNPs) ‘11.8%’ in samples collected in 2011 only, 3 (5.9%) in 2011and 2016, 5 (9.8%) in 2011 and 2020, 5 (9.8%) in 2016 only, 8 (15.7%) in 2016 and 2020, 14 (27.5%) in 2020 and 10 (19.6%) in all the groups. The BLAST revealed that the 2011 isolates were genetically closer to African isolates (53.3%) than Asian ones (46.7%). Interestingly, this proportion changed completely in 2020, to become closer to Asian isolates (81.6%) than to African ones (18.4%). Conclusions Despite the diversity of the identified mutations in the k13-propeller gene, these data did not report widespread artemisinin-resistant polymorphisms in the Jazan region where these samples were collected. Such a process would be expected to increase frequencies of mutations associated with the resistance of ACT.


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