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Biology subjects

Chrzastek, K.

Publications and source records attributed to Chrzastek, K..

3 recordsLinked to original sources

A universal, single primer amplification protocol (R-SPA) to perform whole genome sequencing of segmented dsRNA reoviruses

BackgroundThe Reoviridae family represents the largest family of double-stranded RNA (dsRNA) viruses, and the members have been isolated from a wide range of mammals, birds, reptiles, fishes, insects, plants. Orthoreoviruses, one of the 15 recognized genera in the Reoviridae family, can infect humans and nearly all mammals, and birds. Genomic characterization of reoviruses has not been adopted on a large-scale due to the complexity of obtaining sequences for all 10 segments. ResultsIn this study, we developed a time-efficient, and practical method to enrich reovirus sequencing reads from isolates that allowed for full genome recovery using single-primer amplification method coupled with next generation sequencing. We refer to this protocol as reovirus-Single Primer Amplification (R-SPA). Our results demonstrated that most of the genes were covered with at least 500 reads per base space. Furthermore, R-SPA covered both 5 and 3 end of each reovirus genes. ConclusionA universal and fast amplification protocol that yields double-stranded cDNA in sufficient abundance and facilitates and expedites the whole genome sequencing of reoviruses was presented in this study.

molecular biology↗

A random priming amplification method for whole genome sequencing of SARS-CoV-2 and H1N1 influenza A virus.

BackgroundNon-targeted whole genome sequencing is a powerful tool to comprehensively identify constituents of microbial communities in a sample. There is no need to direct the analysis to any identification before sequencing which can decrease the introduction of bias and false negatives results. It also allows the assessment of genetic aberrations in the genome (e.g., single nucleotide variants, deletions, insertions and copy number variants) including in noncoding protein regions. MethodsThe performance of four different random priming amplification methods to recover RNA viral genetic material of SARS-CoV-2 were compared in this study. In method 1 (H-P) the reverse transcriptase (RT) step was performed with random hexamers whereas in methods 2-4 RT incorporating an octamer primer with a known tag. In methods 1 and 2 (K-P) sequencing was applied on material derived from the RT-PCR step, whereas in methods 3 (SISPA) and 4 (S-P) an additional amplification was incorporated before sequencing. ResultsThe SISPA method was the most effective and efficient method for non-targeted/random priming whole genome sequencing of COVID that we tested. The SISPA method described in this study allowed for whole genome assembly of SARS-CoV-2 and influenza A(H1N1)pdm09 in mixed samples. We determined the limit of detection and characterization of SARS-CoV-2 virus which was 103 pfu/ml (Ct, 22.4) for whole genome assembly and 101 pfu/ml (Ct, 30) for metagenomics detection. ConclusionsThe SISPA method is predominantly useful for obtaining genome sequences from RNA viruses or investigating complex clinical samples as no prior sequence information is needed. It might be applied to monitor genomic virus changes, virus evolution and can be used for fast metagenomics detection or to assess the general picture of different pathogens within the sample.

microbiology↗

Low pathogenic avian influenza virus infection retards colon microbiome diversification in two different chicken lines

A commensal microbiome regulates and is in turn regulated by viruses during host infection which can influence virus infectivity. In this study, analysis of colon microbiome population changes following a low pathogenicity avian influenza virus (AIV) of the H9N2 subtype infection of two different chicken breeds was conducted. Using 16S rRNA sequencing and subsequent data analysis we found reduced microbiome alpha diversity in the acute period of AIV infection (day 2-3) in both Rhode Island Red and VALO chicken lines. From day 4 post infection a gradual increase in diversity of the colon microbiome was observed, but the diversity did not reach the same level as in uninfected chickens by day 10 post infection, suggesting that AIV infection retards the natural accumulation of colon microbiome diversity, which may further influence chicken health following recovery from infection. Beta diversity analysis indicated differences in diversity between the chicken lines during and following acute influenza infection suggesting the impact of host gut microflora dysbiosis following H9N2 influenza virus infection could differ for different breeds.

microbiology↗