scholarly journals Complex Characteristics of Yersinia pestis Strains Isolated in the Sarydzhaz and Upper-Naryn High-Mountain Foci in 2019–2020

Author(s):  
L. M. Kukleva ◽  
A. K. Dzhaparova ◽  
E. G. Oglodin ◽  
E. A. Naryshkina ◽  
Ya. M. Krasnov ◽  
...  

The aim of the study was a comprehensive analysis of the phenotypic and genetic properties of Yersinia pestis strains isolated in the Sarydzhaz and Upper-Naryn high-mountain foci of the Tien Shan in 2019–2020; determination of the present-day population structure and areal of these highly virulent strains of the plague pathogen.Materials and methods. Studies of biochemical properties (fermentation of carbohydrates, nutritional requirements), virulence (in vitro and in laboratory animals), molecular-genetic analysis and whole genome sequencing of Y. pestis strains isolated in the Sarydzhaz and Upper-Naryn high-mountain foci in 2019–2020 have been carried out. We used Y. pestis strains from the foci of the Tien Shan and Pamir-Alai dated 1928–2016 for the comparison. Whole genome sequencing was performed using the Ion S5 XL System. Phylogenetic analysis was performed on the basis of 1443 identified core SNPs in 36 Y. pestis strains of various phylogenetic lines included in the analysis. The construction of dendrograms was carried out using the Maximum Likelihood algorithm, PHYML program, HKY85 model.Results and discussion. It is established that all Y. pestis strains isolated in the Sarydzhaz and Upper-Naryn high-mountain foci in 2019–2020 belong to the 0.ANT5 phylogenetic branch of the ancient biovar of the main subspecies. Genome-wide sequencing revealed the presence of two 0.ANT5 clones, the first of which consists of strains from the basin of the river Kooylu in the Sarydzhaz focus, dated 2020. The second powerful clone includes the strains of 2012–2020 isolated in the Sarydzhaz and Upper-Naryn foci. The high virulence of the isolated strains has been shown. It was concluded that further study of the territories of the highmountain foci of the Tien Shan and Pamir-Alai is necessary to establish the current boundaries of the 0.ANT5 areal, as well as to identify the circulation areas of Y. pestis of other phylogenetic lineages. 

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Weili Cai ◽  
Schyler Nunziata ◽  
John Rascoe ◽  
Michael J. Stulberg

AbstractHuanglongbing (HLB) is a worldwide deadly citrus disease caused by the phloem-limited bacteria ‘Candidatus Liberibacter asiaticus’ (CLas) vectored by Asian citrus psyllids. In order to effectively manage this disease, it is crucial to understand the relationship among the bacterial isolates from different geographical locations. Whole genome sequencing approaches will provide more precise molecular characterization of the diversity among populations. Due to the lack of in vitro culture, obtaining the whole genome sequence of CLas is still a challenge, especially for medium to low titer samples. Hundreds of millions of sequencing reads are needed to get good coverage of CLas from an HLB positive citrus sample. In order to overcome this limitation, we present here a new method, Agilent SureSelect XT HS target enrichment, which can specifically enrich CLas from a metagenomic sample while greatly reducing cost and increasing whole genome coverage of the pathogen. In this study, the CLas genome was successfully sequenced with 99.3% genome coverage and over 72X sequencing coverage from low titer tissue samples (equivalent to 28.52 Cq using Li 16 S qPCR). More importantly, this method also effectively captures regions of diversity in the CLas genome, which provides precise molecular characterization of different strains.


2021 ◽  
Author(s):  
◽  
Mariah Taylor ◽  

Two RNA virus families that pose a threat to human and animal health are Hantaviridae and Coronaviridae. These RNA viruses which originate in wildlife continue and will continue to cause disease, and hence, it is critical that scientific research define the mechanisms as to how these viruses spillover and adapt to new hosts to become endemic. One gap in our ability to define these mechanisms is the lack of whole genome sequences for many of these viruses. To address this specific gap, I developed a versatile amplicon-based whole-genome sequencing (WGS) approach to identify viral genomes of hantaviruses and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) within reservoir and spillover hosts. In my research studies, I used the amplicon-based WGS approach to define the genetic plasticity of viral RNA within pathogenic and nonpathogenic hantavirus species. The standing genetic variation of Andes orthohantavirus and Prospect Hill orthohantavirus was mapped out and amino acid changes occurring outside of functional domains were identified within the nucleocapsid and glycoprotein. I observed several amino acid changes in functional domains of the RNA-dependent RNA polymerase, as well as single nucleotide polymorphisms (SNPs) within the 3’ non-coding region (NCR) of the S-segment. To identify whether virus adaptation would occur within the S- and L-segments we attempted to adapt hantaviruses in vitro in a spillover host model through passaging experiments. In early passages we identified few mutations in the M-segment with the majority being identified in the S-segment 3’ NCR and the L-segment. This work suggests that hantavirus adaptation occurs in the S- and L-segments although the effect of these mutants on pathology is yet to be determined. While sequencing laboratory isolates is easily accomplished, sequencing low concentrations of virus within the reservoir is a formidable task. I further translated our amplicon-based WGS approach into a pan-oligonucleotide amplicon-based WGS approach to sequence hantavirus vRNA and mRNA from reservoir and spillover hosts in Ukraine. This approach successfully identified a novel Puumala orthohantavirus (PUUV) strain in Ukraine and using Bayesian phylogenetics we found this strain to be associated with the PUUV Latvian lineage. Early during the SARS-CoV-2 pandemic, I applied the knowledge gained in the hantavirus WGS efforts to sequencing of SARS-CoV-2 from nasopharyngeal swabs collected in April 2020. The genetic diversity of 45 SARS-CoV-2 isolates was evaluated with the methods I developed. We identified D614G, a notable mutation known for increasing transmission, in over 90% of our isolates. Two major lineages distinguish SARS-CoV-2 variants worldwide, lineages A and B. While most of our isolates were found within B lineage, we also identified one isolate within lineage A. We performed in vitro work which confirmed A lineage isolates as having poor replication in the trachea as compared to the nasal cavity. Five of these isolates presented a unique array of mutations which were assessed in the keratin 18 human angiotensin-converting enzyme 2 (K18-hACE2) mouse model for its response immunologically and pathogenically. We identified a distinction of pathogenesis between the A and B lineages with emphysema being common amongst A lineage isolates. Additionally, we discovered a small cohort of likely SNPs that defined the late induction of eosinophils during infection. In summary, this work will further define the dynamics of genetic variation and plasticity within virus populations that cause disease outbreaks and will allow a deeper understanding of the virus-host relationship.


Viruses ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 1038 ◽  
Author(s):  
Jennifer H. Kopanke ◽  
Justin S. Lee ◽  
Mark D. Stenglein ◽  
Christie E. Mayo

Bluetongue virus (BTV) is an arbovirus that has been associated with dramatic epizootics in both wild and domestic ruminants in recent decades. As a segmented, double-stranded RNA virus, BTV can evolve via several mechanisms due to its genomic structure. However, the effect of BTV’s alternating-host transmission cycle on the virus’s genetic diversification remains poorly understood. Whole genome sequencing approaches offer a platform for investigating the effect of host-alternation across all ten segments of BTV’s genome. To understand the role of alternating hosts in BTV’s genetic diversification, a field isolate was passaged under three different conditions: (i) serial passages in Culicoides sonorensis cells, (ii) serial passages in bovine pulmonary artery endothelial cells, or (iii) alternating passages between insect and bovine cells. Aliquots of virus were sequenced, and single nucleotide variants were identified. Measures of viral population genetics were used to quantify the genetic diversification that occurred. Two consensus variants in segments 5 and 10 occurred in virus from all three conditions. While variants arose across all passages, measures of genetic diversity remained largely similar across cell culture conditions. Despite passage in a relaxed in vitro system, we found that this BTV isolate exhibited genetic stability across passages and conditions. Our findings underscore the valuable role that whole genome sequencing may play in improving understanding of viral evolution and highlight the genetic stability of BTV.


2016 ◽  
Vol 60 (9) ◽  
pp. 5515-5520 ◽  
Author(s):  
Patrick F. McDermott ◽  
Gregory H. Tyson ◽  
Claudine Kabera ◽  
Yuansha Chen ◽  
Cong Li ◽  
...  

ABSTRACTLaboratory-basedin vitroantimicrobial susceptibility testing is the foundation for guiding anti-infective therapy and monitoring antimicrobial resistance trends. We used whole-genome sequencing (WGS) technology to identify known antimicrobial resistance determinants among strains of nontyphoidalSalmonellaand correlated these with susceptibility phenotypes to evaluate the utility of WGS for antimicrobial resistance surveillance. Six hundred fortySalmonellaof 43 different serotypes were selected from among retail meat and human clinical isolates that were tested for susceptibility to 14 antimicrobials using broth microdilution. The MIC for each drug was used to categorize isolates as susceptible or resistant based on Clinical and Laboratory Standards Institute clinical breakpoints or National Antimicrobial Resistance Monitoring System (NARMS) consensus interpretive criteria. Each isolate was subjected to whole-genome shotgun sequencing, and resistance genes were identified from assembled sequences. A total of 65 unique resistance genes, plus mutations in two structural resistance loci, were identified. There were more unique resistance genes (n =59) in the 104 human isolates than in the 536 retail meat isolates (n =36). Overall, resistance genotypes and phenotypes correlated in 99.0% of cases. Correlations approached 100% for most classes of antibiotics but were lower for aminoglycosides and beta-lactams. We report the first finding of extended-spectrum β-lactamases (ESBLs) (blaCTX-M1andblaSHV2a) in retail meat isolates ofSalmonellain the United States. Whole-genome sequencing is an effective tool for predicting antibiotic resistance in nontyphoidalSalmonella, although the use of more appropriate surveillance breakpoints and increased knowledge of new resistance alleles will further improve correlations.


2015 ◽  
Vol 25 (3) ◽  
pp. 426-434 ◽  
Author(s):  
Brock A. Peters ◽  
Bahram G. Kermani ◽  
Oleg Alferov ◽  
Misha R. Agarwal ◽  
Mark A. McElwain ◽  
...  

Author(s):  
G. A. Eroshenko ◽  
N. V. Popov ◽  
Zh. V. Al’khova ◽  
A. N. Balykova ◽  
L. M. Kukleva ◽  
...  

Objective of the study – comparative phylogenetic analysis of Yersinia pestis strains, isolated in Precaspian North-Western steppe focus in 1924–1926, 1972, and 1986–1990 to understand the causes of focal reactivation during different time periods of the XX century.Materials and methods. The work included 30 strains of Yersinia pestis from Precaspian North-Western steppe natural focus and adjacent plague foci. Whole genome sequencing of eight Y. pestis strains from the former was carried out. Also whole-genome sequences of 16 strains from neighboring natural foci were used. Whole-genome sequencing of Y. pestis strains was conducted in Ion PGM system (Life technologies). SNPs search across the core genome was performed using software package Wombac 2.0. Tree diagram Maximum Likelihood, HKU85 model, was constructed to analyze phylogenetic relations.Results and discussion. It is established that in early XX century (1924–1926), strains of phylogenetic branches 2.MED4 and 2.MED1, belonging to medieval biovar, main subspecies, circulated on Ergenin Upland in the Precaspian North-Western steppe natural focus. Later on they became extinct in the territory. It is shown that the strains, isolated on Ergenin Upland in 1972, constituted a common subcluster on the dendrogram with the strains from low-mountain and piedmont plague foci of Caucasus and Transcaucasia, dated the same time period. It was inferred that epizootic manifestations on Ergenin upland in 1972, after a long recess since 1938, were caused by importation of Y. pestis strains from low-mountain natural plague foci of Caucasus and Transcaucasia. It was noted that expansion of Caucasian strains was of short-term character, and plague infected animals have not been found on Ergenin Upland since 1974 (including modern period). It is established that Y. pestis strains isolated in the eastern part of Precaspian North-Western steppe focus between 1986 and 1990, do not have close genetic relation to the strains that circulated on Ergenin Upland in 1924–1926 and 1972. It is determined that each epizootic period (1913–1938 and 1972–1973) in Precaspian North-Western steppe natural focus culminated in the elimination of the circulating Y. pestis strains and rehabilitation of the focal territory. 


Author(s):  
Wentao Chen ◽  
David Šmajs ◽  
Yongfei Hu ◽  
Wujian Ke ◽  
Petra Pospíšilová ◽  
...  

Abstract Background Whole-genome sequencing (WGS) of Treponema pallidum subspecies pallidum (TPA) has been constrained by the lack of in vitro cultivation methods for isolating spirochetes from patient samples. Methods We built upon recently developed enrichment methods to sequence TPA directly from primary syphilis chancre swabs collected in Guangzhou, China. Results By combining parallel, pooled whole-genome amplification with hybrid selection, we generated high-quality genomes from 4 of 8 chancre-swab samples and 2 of 2 rabbit-passaged isolates, all subjected to challenging storage conditions. Conclusions This approach enabled the first WGS of Chinese samples without rabbit passage and provided insights into TPA genetic diversity in China.


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