The utility of new highly accurate long reads, or HiFi reads, was first demonstrated for calling all variant types in human genomes. It has since been shown that HiFi reads…
Dr. Wenger gives attendees an update on PacBio’s long-read sequencing and variant detection capabilities on the Sequel II System and shares recommendations on how to design your own study using…
COVID-19 is caused by the infection of SARS-CoV-2, a member of the coronavirus family. Complete and accurate sequencing of the SARS-CoV-2 genome enables discovery and epidemiological tracing of mutations that…
Introduction: Around 5% (1,168) of protein-coding genes in the human genome contain an exon that is difficult to map with typical next-generation sequencing (NGS) read lengths due to homologous pseudogenes…
In this ASHG 2020 CoLab presentation hear Principal Scientists, Aaron Wenger and Elizabeth Tseng share how highly accurate long reads (HiFi reads) provide comprehensive variant detection for both genomes and…
Long-read mRNA sequencing such as PacBio’s Iso-Seq method offer high-throughput transcriptome profiling that circumvents the transcript assembly problem by sequencing full-length cDNA. The Iso-Seq method has emerged as the most…
Most genes in eukaryotic organisms produce alternative isoforms, broadening the diversity of proteins and non-coding RNAs encoded by the genome. In contrast to other RNA sequencing platforms that rely on…
Although PCR is a cost-effective way to enrich for genomic regions of interest for DNA sequencing, amplifying regions with extreme GC-content and long stretches of short tandem repeat (STR) sequences…
Recent advances in sequencing chemistry and software in the Sequel II System enable generating highly accurate long reads that are up to 25 kb in length with >99% accuracy. The…
In this ASHG 2020 PacBio Workshop Jonas Korlach, CSO, shares how the new PacBio Sequel IIe System makes highly accurate long-read sequencing easy and affordable so?all scientists can gain comprehensive…
Complete, high-quality microbial genomes are very valuable across a broad array of fields, from environmental studies, to human microbiome health, food pathogen surveillance, etc. Long-read sequencing enables accurate resolution of…
The widespread occurrence of repetitive stretches of DNA in genomes of organisms across the tree of life imposes fundamental challenges for sequencing, genome assembly, and automated annotation of genes and proteins. This multi-level problem can lead to errors in genome and protein databases that are often not recognized or acknowledged. As a consequence, end users working with sequences with repetitive regions are faced with ‘ready-to-use’ deposited data whose trustworthiness is difficult to determine, let alone to quantify. Here, we provide a review of the problems associated with tandem repeat sequences that originate from different stages during the sequencing-assembly-annotation-deposition workflow, and that may proliferate in public database repositories affecting all downstream analyses. As a case study, we provide examples of the Atlantic cod genome, whose sequencing and assembly were hindered by a particularly high prevalence of tandem repeats. We complement this case study with examples from other species, where mis-annotations and sequencing errors have propagated into protein databases. With this review, we aim to raise the awareness level within the community of database users, and alert scientists working in the underlying workflow of database creation that the data they omit or improperly assemble may well contain important biological information valuable to others. © The Author(s) 2019. Published by Oxford University Press on behalf of Nucleic Acids Research.
A Gram-stain-negative bacterial strain, designated CA10T, was isolated from bovine raw milk sampled in Anseong, Republic of Korea. Cells were yellow-pigmented, aerobic, non-motile bacilli and grew optimally at 30?°C and pH 7.0 on tryptic soy agar without supplementation of NaCl. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that strain CA10T belonged to the genus Chryseobacterium, family Flavobacteriaceae, and was most closely related to Chryseobacterium indoltheticum ATCC 27950T (98.75?% similarity). The average nucleotide identity and digital DNA-DNA hybridization values of strain CA10T were 94.4 and 56.9?%, respectively, relative to Chryseobacterium scophthalmum DSM 16779T, being lower than the cut-off values of 95-96?and 70?%, respectively. The predominant respiratory quinone was menaquinone-6; major polar lipid, phosphatidylethanolamine; major fatty acids, iso-C15?:?0, summed feature 9 (iso-C17?:?1?9c and/or C16?:?0 10-methyl), summed feature 3 (iso-C15?:?0 2-OH and/or C16?:?1?7c) and iso-C17?:?0 3-OH. The results of physiological, chemotaxonomic and biochemical analyses suggested that strain CA10T is a novel species of genus Chryseobacterium, for which the name Chryseobacterium mulctrae sp. nov. is proposed. The type strain is CA10T (=KACC 21234T=JCM 33443T).
A Gram-stain-negative, rod-shaped and red-pigmented strain, HME7025T, was isolated from freshwater sampled in the Republic of Korea. Phylogenetic analysis based on its 16S rRNA gene sequence revealed that strain HME7025T formed a lineage within the family Cytophagaceae of the phylum Bacteroidetes. Strain HME7025T was closely related to the genera Pseudarcicella, Arcicella and Flectobacillus. The 16S rRNA gene sequence similarity values of strain HME7025T were under 94.5?% to its closest phylogenetic neighbours. The major fatty acids of strain HME7025T were iso-C15?:?0 (41.9?%), summed feature 3 (comprising C16?:?1?7c and/or C16?:?1?6c; 12.2?%) and anteiso-C15?:?0 (10.8?%). The major respiratory quinone was menaquinone-7. The major polar lipids were phosphatidylethanolamine, two unidentified aminophospholipids and one unidentified polar lipid. The DNA G+C content of strain HME7025T was 37.9?mol%. On the basis of the evidence presented in this study, strain HME7025T represents a novel species of a novel genus within the family Cytophagaceae, for which the name Allopseudarcicella aquatilis gen. nov., sp. nov. is proposed. The type strain is HME7025T (=KCTC 23617T=CECT 7957T).
Horizontal transfer of plasmids encoding antimicrobial-resistance and virulence determinants has been instrumental in Staphylococcus aureus evolution, including the emergence of community-associated methicillin-resistant S. aureus (CA-MRSA). In the early 1990s the first CA-MRSA isolated in Western Australia (WA), WA-5, encoded cadmium, tetracycline and penicillin-resistance genes on plasmid pWBG753 (~30 kb). WA-5 and pWBG753 appeared only briefly in WA, however, fusidic-acid-resistance plasmids related to pWBG753 were also present in the first European CA-MRSA at the time. Here we characterized a 72-kb conjugative plasmid pWBG731 present in multiresistant WA-5-like clones from the same period. pWBG731 was a cointegrant formed from pWBG753 and a pWBG749-family conjugative plasmid. pWBG731 carried mupirocin, trimethoprim, cadmium and penicillin-resistance genes. The stepwise evolution of pWBG731 likely occurred through the combined actions of IS257, IS257-dependent miniature inverted-repeat transposable elements (MITEs) and the BinL resolution system of the ß-lactamase transposon Tn552 An evolutionary intermediate ~42-kb non-conjugative plasmid pWBG715, possessed the same resistance genes as pWBG731 but retained an integrated copy of the small tetracycline-resistance plasmid pT181. IS257 likely facilitated replacement of pT181 with conjugation genes on pWBG731, thus enabling autonomous transfer. Like conjugative plasmid pWBG749, pWBG731 also mobilized non-conjugative plasmids carrying oriT mimics. It seems likely that pWBG731 represents the product of multiple recombination events between the WA-5 pWBG753 plasmid and other mobile genetic elements present in indigenous CA-MSSA. The molecular evolution of pWBG731 saliently illustrates how diverse mobile genetic elements can together facilitate rapid accrual and horizontal dissemination of multiresistance in S. aureus CA-MRSA.Copyright © 2019 American Society for Microbiology.
If you have a question, need to check the status of an order, or are interested in purchasing an instrument, we're here to help.