In this PacBio User Group Meeting presentation, Tim Smith of the USDA’s Agricultural Research Service describes efforts to generate reference-grade genome assemblies for various bovine species and analyze them to understand factors such as how selective breeding has affected certain breeds. Genome assemblies he presents span cattle, water buffalo, and gaur. Smith shows data for each assembly, noting that as data production shifted to the Sequel System, long-read PacBio data became even better at producing highly contiguous assemblies.
In this PacBio User Group Meeting presentation, PacBio scientist Kristin Mars speaks about recent updates, such as the single-day library prep that’s now possible with the Iso-Seq Express workflow. She also notes that one SMRT Cell 8M is sufficient for most Iso-Seq experiments for whole transcriptome sequencing at an affordable price.
The goat (Capra hircus) remains an important livestock species due to the species’ ability to forage and provide milk, meat and wool in arid environments. The current goat reference assembly and annotation borrows heavily from other loosely related livestock species, such as cattle, and may not reflect the unique structural and functional characteristics of the species. We present preliminary data from a new de novo reference assembly for goat that primarily utilizes 38 million PacBio P5-C3 reads generated from an inbred San Clemente goat. This assembly consists of only 5,902 contigs with a contig N50 size of 2.56 megabases which…
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…
Background Assemblies of diploid genomes are generally unphased, pseudo-haploid representations that do not correctly reconstruct the two parental haplotypes present in the individual sequenced. Instead, the assembly alternates between parental haplotypes and may contain duplications in regions where the parental haplotypes are sufficiently different. Trio binning is an approach to genome assembly that uses short reads from both parents to classify long reads from the offspring according to maternal or paternal haplotype origin, and is thus helped rather than impeded by heterozygosity. Using this approach, it is possible to derive two assemblies from an individual, accurately representing both parental contributions…
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…
Lactic acid bacteria (LAB) confer health benefits to human when administered orally. We have recently isolated several species of LAB strains from plant sources, such as fruits, vegetables, flowers, and medicinal plants. Since antibiotics used to treat bacterial infection diseases induce the emergence of drug-resistant bacteria in intestinal microflora, it is important to evaluate the susceptibility of LAB strains to antibiotics to ensure the safety and security of processed foods. The aim of the present study is to determine the minimum inhibitory concentration (MIC) of antibiotics against several plant-derived LAB strains. When aminoglycoside antibiotics, such as streptomycin (SM), kanamycin (KM), and…
The evolution and global transmission of antimicrobial resistance has been well documented in Gram-negative bacteria and healthcare-associated epidemic pathogens, often emerging from regions with heavy antimicrobial use. However, the degree to which similar processes occur with Gram-positive bacteria in the community setting is less well understood. Here, we trace the recent origins and global spread of a multidrug resistant, community-associated Staphylococcus aureus lineage from the Indian subcontinent, the Bengal Bay clone (ST772). We generated whole genome sequence data of 340 isolates from 14 countries, including the first isolates from Bangladesh and India, to reconstruct the evolutionary history and genomic epidemiology…
The ruminants are one of the most successful mammalian lineages, exhibiting morphological and habitat diversity and containing several key livestock species. To better understand their evolution, we generated and analyzed de novo assembled genomes of 44 ruminant species, representing all six Ruminantia families. We used these genomes to create a time-calibrated phylogeny to resolve topological controversies, overcoming the challenges of incomplete lineage sorting. Population dynamic analyses show that population declines commenced between 100,000 and 50,000 years ago, which is concomitant with expansion in human populations. We also reveal genes and regulatory elements that possibly contribute to the evolution of the…
The bacteriophage exclusion (BREX) system is a novel prokaryotic defense system against bacteriophages. To our knowledge, no study has systematically characterized the function of the BREX system in lactic acid bacteria. Lactobacillus casei Zhang is a probiotic bacterium originating from koumiss. By using single-molecule real-time sequencing, we previously identified N6-methyladenine (m6A) signatures in the genome of L. casei Zhang and a putative methyltransferase (MTase), namely, pglX This work further analyzed the genomic locus near the pglX gene and identified it as a component of the BREX system. To decipher the biological role of pglX, an L. casei Zhang pglX mutant…
Acinetobacter baumannii is an important Gram-negative pathogen in hospital-related infections. However, treatment options for A. baumannii infections have become limited due to multidrug resistance. Bacterial virulence is often associated with capsule genes found in the K locus, many of which are essential for biosynthesis of the bacterial envelope. However, the roles of other genes in the K locus remain largely unknown. From an in vitro evolution experiment, we obtained an isolate of the virulent and multidrug-resistant A. baumannii strain MDR-ZJ06, called MDR-ZJ06M, which has an insertion by the ISAba16 transposon in gnaA (encoding UDP-N-acetylglucosamine C-6 dehydrogenase), a gene found in…
HIV elite controllers represent a remarkable minority of patients who maintain normal CD4+ T-cell counts and low or undetectable viral loads for decades in the absence of antiretroviral therapy. To examine the possible contribution of virus attenuation to elite control, we obtained a primary HIV-1 isolate from an elite controller who had been infected for 19?years, the last 10 of which were in the absence of antiretroviral therapy. Full-length sequencing of this isolate revealed a highly unusual V1 domain in Envelope (Env). The V1 domain in this HIV-1 strain was 49 amino acids, placing it in the top 1% of…
Salmonella enterica serovar Fresno is an infrequently isolated serovar whose ecology and genomic characteristics have not yet been described. To further understand the genomic characteristics of this serovar, we sequenced the complete genome of a single isolate recovered from a bovine lymph node at harvest.
Lacerta viridis and Lacerta bilineata are sister species of European green lizards (eastern and western clades, respectively) that, until recently, were grouped together as the L. viridis complex. Genetic incompatibilities were observed between lacertid populations through crossing experiments, which led to the delineation of two separate species within the L. viridis complex. The population history of these sister species and processes driving divergence are unknown. We constructed the first high-quality de novo genome assemblies for both L. viridis and L. bilineata through Illumina and PacBio sequencing, with annotation support provided from transcriptome sequencing of several tissues. To estimate gene flow…
A bacterial strain designated as P08T was isolated from laboratory tap water during a water quality assessment in University of Malaya, Malaysia. The strain was a Gram-negative, rod-shaped, nonmotile, and aerobic bacterium. Complete genome of P08T comprised of a 2,820,660 bp chromosome with a G + C content of 36.43%. Both 16S rRNA phylogeny and phylogenetic tree inferred from the core gene matrix demonstrated that P08T formed a hitherto unknown subline within the family Neisseriaceae. Ortho average nucleotide identity (OrthoANI) values and the percentage of conserved proteins (POCP) calculated from complete genome sequence indicated low relatedness between P08T and its phylogenetic neighbors. Respiratory…