Menu
July 7, 2019

Complete genome sequence of Pseudomonas fluorescens LBUM636, a strain with biocontrol capabilities against late blight of potato.

Herein provided is the full-genome sequence of Pseudomonas fluorescens LBUM636. This strain is a plant growth-promoting rhizobacterium (PGPR) which produces phenazine-1-carboxylic acid, an antibiotic involved in the biocontrol of numerous plant pathogens, including late blight of potato caused by the plant pathogen Phytophthora infestans. Copyright © 2016 Morrison et al.


July 7, 2019

Microevolution of monophasic Salmonella Typhimurium during epidemic, United Kingdom, 2005-2010.

Microevolution associated with emergence and expansion of new epidemic clones of bacterial pathogens holds the key to epidemiologic success. To determine microevolution associated with monophasic Salmonella Typhimurium during an epidemic, we performed comparative whole-genome sequencing and phylogenomic analysis of isolates from the United Kingdom and Italy during 2005-2012. These isolates formed a single clade distinct from recent monophasic epidemic clones previously described from North America and Spain. The UK monophasic epidemic clones showed a novel genomic island encoding resistance to heavy metals and a composite transposon encoding antimicrobial drug resistance genes not present in other Salmonella Typhimurium isolates, which may have contributed to epidemiologic success. A remarkable amount of genotypic variation accumulated during clonal expansion that occurred during the epidemic, including multiple independent acquisitions of a novel prophage carrying the sopE gene and multiple deletion events affecting the phase II flagellin locus. This high level of microevolution may affect antigenicity, pathogenicity, and transmission.


July 7, 2019

Complete genome sequence of the Mycobacterium immunogenum type strain CCUG 47286.

Here, we report the complete genome sequence of Mycobacterium immunogenum type strain CCUG 47286, a nontuberculous mycobacterium. The whole genome has 5,573,781 bp and covers as many as 5,484 predicted genes. This genome contributes to the task of closing the still-existing gap of genomes of rapidly growing mycobacterial type strains. Copyright © 2016 Jaén-Luchoro et al.


July 7, 2019

Complete genome sequence of Klebsiella quasipneumoniae subsp. similipneumoniae strain ATCC 700603.

Klebsiella quasipneumoniae subsp. similipneumoniae strain ATCC 700603, formerly known as K. pneumoniae K6, is known for producing extended-spectrum ß-lactamase (ESBL) enzymes that can hydrolyze oxyimino-ß-lactams, resulting in resistance to these drugs. We herein report the complete genome of strain ATCC 700603 and show that the ESBL genes are plasmid-encoded. Copyright © 2016 Elliott et al.


July 7, 2019

The channel catfish genome sequence provides insights into the evolution of scale formation in teleosts.

Catfish represent 12% of teleost or 6.3% of all vertebrate species, and are of enormous economic value. Here we report a high-quality reference genome sequence of channel catfish (Ictalurus punctatus), the major aquaculture species in the US. The reference genome sequence was validated by genetic mapping of 54,000 SNPs, and annotated with 26,661 predicted protein-coding genes. Through comparative analysis of genomes and transcriptomes of scaled and scaleless fish and scale regeneration experiments, we address the genomic basis for the most striking physical characteristic of catfish, the evolutionary loss of scales and provide evidence that lack of secretory calcium-binding phosphoproteins accounts for the evolutionary loss of scales in catfish. The channel catfish reference genome sequence, along with two additional genome sequences and transcriptomes of scaled catfishes, provide crucial resources for evolutionary and biological studies. This work also demonstrates the power of comparative subtraction of candidate genes for traits of structural significance.


July 7, 2019

Direct repeat-mediated DNA deletion of the mating type MAT1-2 genes results in unidirectional mating type switching in Sclerotinia trifoliorum.

The necrotrophic fungal pathogen Sclerotinia trifoliorum exhibits ascospore dimorphism and unidirectional mating type switching – self-fertile strains derived from large ascospores produce both self-fertile (large-spores) and self-sterile (small-spores) offsprings in a 4:4 ratio. The present study, comparing DNA sequences at MAT locus of both self-fertile and self-sterile strains, found four mating type genes (MAT1-1-1, MAT1-1-5, MAT1-2-1 and MAT1-2-4) in the self-fertile strain. However, a 2891-bp region including the entire MAT1-2-1 and MAT1-2-4 genes had been completely deleted from the MAT locus in the self-sterile strain. Meanwhile, two copies of a 146-bp direct repeat motif flanking the deleted region were found in the self-fertile strain, but only one copy of this 146-bp motif (a part of the MAT1-1-1 gene) was present in the self-sterile strain. The two direct repeats were believed to be responsible for the deletion through homologous intra-molecular recombination in meiosis. Tetrad analyses showed that all small ascospore-derived strains lacked the missing DNA between the two direct repeats that was found in all large ascospore-derived strains. In addition, heterokaryons at the MAT locus were observed in field isolates as well as in laboratory derived isolates.


July 7, 2019

ABO allele-level frequency estimation based on population-scale genotyping by next generation sequencing.

The characterization of the ABO blood group status is vital for blood transfusion and solid organ transplantation. Several methods for the molecular characterization of the ABO gene, which encodes the alleles that give rise to the different ABO blood groups, have been described. However, the application of those methods has so far been restricted to selected samples and not been applied to population-scale analysis.We describe a cost-effective method for high-throughput genotyping of the ABO system by next generation sequencing. Sample specific barcodes and sequencing adaptors are introduced during PCR, rendering the products suitable for direct sequencing on Illumina MiSeq or HiSeq instruments. Complete sequence coverage of exons 6 and 7 enables molecular discrimination of the ABO subgroups and many alleles. The workflow was applied to ABO genotype more than a million samples. We report the allele group frequencies calculated on a subset of more than 110,000 sampled individuals of German origin. Further we discuss the potential of the workflow for high resolution genotyping taking the observed allele group frequencies into account. Finally, sequence analysis revealed 287 distinct so far not described alleles of which the most abundant one was identified in 174 samples.The described workflow delivers high resolution ABO genotyping at low cost enabling population-scale molecular ABO characterization.


July 7, 2019

SimLoRD: Simulation of Long Read Data.

Third generation sequencing methods provide longer reads than second generation methods and have distinct error characteristics. While there exist many read simulators for second generation data, there is a very limited choice for third generation data.We analyzed public data from Pacific Biosciences (PacBio) SMRT sequencing, developed an error model and implemented it in a new read simulator called SimLoRD. It offers options to choose the read length distribution and to model error probabilities depending on the number of passes through the sequencer. The new error model makes SimLoRD the most realistic SMRT read simulator available.SimLoRD is available open source at http://bitbucket.org/genomeinformatics/simlord/ and installable via Bioconda (http://bioconda.github.io).Bianca.Stoecker@uni-due.de or Sven.Rahmann@uni-due.deSupplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.


July 7, 2019

Minimap and miniasm: fast mapping and de novo assembly for noisy long sequences.

Single Molecule Real-Time (SMRT) sequencing technology and Oxford Nanopore technologies (ONT) produce reads over 10?kb in length, which have enabled high-quality genome assembly at an affordable cost. However, at present, long reads have an error rate as high as 10-15%. Complex and computationally intensive pipelines are required to assemble such reads.We present a new mapper, minimap and a de novo assembler, miniasm, for efficiently mapping and assembling SMRT and ONT reads without an error correction stage. They can often assemble a sequencing run of bacterial data into a single contig in a few minutes, and assemble 45-fold Caenorhabditis elegans data in 9?min, orders of magnitude faster than the existing pipelines, though the consensus sequence error rate is as high as raw reads. We also introduce a pairwise read mapping format and a graphical fragment assembly format, and demonstrate the interoperability between ours and current tools.https://github.com/lh3/minimap and https://github.com/lh3/miniasmhengli@broadinstitute.orgSupplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.


July 7, 2019

A hot L1 retrotransposon evades somatic repression and initiates human colorectal cancer.

Although human LINE-1 (L1) elements are actively mobilized in many cancers, a role for somatic L1 retrotransposition in tumor initiation has not been conclusively demonstrated. Here, we identify a novel somatic L1 insertion in the APC tumor suppressor gene that provided us with a unique opportunity to determine whether such insertions can actually initiate colorectal cancer (CRC), and if so, how this might occur. Our data support a model whereby a hot L1 source element on Chromosome 17 of the patient’s genome evaded somatic repression in normal colon tissues and thereby initiated CRC by mutating the APC gene. This insertion worked together with a point mutation in the second APC allele to initiate tumorigenesis through the classic two-hit CRC pathway. We also show that L1 source profiles vary considerably depending on the ancestry of an individual, and that population-specific hot L1 elements represent a novel form of cancer risk. © 2016 Scott et al.; Published by Cold Spring Harbor Laboratory Press.


July 7, 2019

Whole genome DNA sequence analysis of Salmonella subspecies enterica serotype Tennessee obtained from related peanut butter foodborne outbreaks.

Establishing an association between possible food sources and clinical isolates requires discriminating the suspected pathogen from an environmental background, and distinguishing it from other closely-related foodborne pathogens. We used whole genome sequencing (WGS) to Salmonella subspecies enterica serotype Tennessee (S. Tennessee) to describe genomic diversity across the serovar as well as among and within outbreak clades of strains associated with contaminated peanut butter. We analyzed 71 isolates of S. Tennessee from disparate food, environmental, and clinical sources and 2 other closely-related Salmonella serovars as outgroups (S. Kentucky and S. Cubana), which were also shot-gun sequenced. A whole genome single nucleotide polymorphism (SNP) analysis was performed using a maximum likelihood approach to infer phylogenetic relationships. Several monophyletic lineages of S. Tennessee with limited SNP variability were identified that recapitulated several food contamination events. S. Tennessee clades were separated from outgroup salmonellae by more than sixteen thousand SNPs. Intra-serovar diversity of S. Tennessee was small compared to the chosen outgroups (1,153 SNPs), suggesting recent divergence of some S. Tennessee clades. Analysis of all 1,153 SNPs structuring an S. Tennessee peanut butter outbreak cluster revealed that isolates from several food, plant, and clinical isolates were very closely related, as they had only a few SNP differences between them. SNP-based cluster analyses linked specific food sources to several clinical S. Tennessee strains isolated in separate contamination events. Environmental and clinical isolates had very similar whole genome sequences; no markers were found that could be used to discriminate between these sources. Finally, we identified SNPs within variable S. Tennessee genes that may be useful markers for the development of rapid surveillance and typing methods, potentially aiding in traceback efforts during future outbreaks. Using WGS can delimit contamination sources for foodborne illnesses across multiple outbreaks and reveal otherwise undetected DNA sequence differences essential to the tracing of bacterial pathogens as they emerge.


July 7, 2019

Extensive sequencing of seven human genomes to characterize benchmark reference materials.

The Genome in a Bottle Consortium, hosted by the National Institute of Standards and Technology (NIST) is creating reference materials and data for human genome sequencing, as well as methods for genome comparison and benchmarking. Here, we describe a large, diverse set of sequencing data for seven human genomes; five are current or candidate NIST Reference Materials. The pilot genome, NA12878, has been released as NIST RM 8398. We also describe data from two Personal Genome Project trios, one of Ashkenazim Jewish ancestry and one of Chinese ancestry. The data come from 12 technologies: BioNano Genomics, Complete Genomics paired-end and LFR, Ion Proton exome, Oxford Nanopore, Pacific Biosciences, SOLiD, 10X Genomics GemCode WGS, and Illumina exome and WGS paired-end, mate-pair, and synthetic long reads. Cell lines, DNA, and data from these individuals are publicly available. Therefore, we expect these data to be useful for revealing novel information about the human genome and improving sequencing technologies, SNP, indel, and structural variant calling, and de novo assembly.


Talk with an expert

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.