Menu

Asset Tag: long-read sequencing

July 7, 2019

Complete genome sequence of Clostridium carboxidivorans P7(T), a syngas-fermenting bacterium capable of producing long-chain alcohols.

Clostridium carboxidivorans P7(T) is an anaerobe that can ferment syngas (mainly CO or CO2 and H2) to produce acids (acetic and butyric acid), ethanol and long-chain alcohols (butanol and hexanol). Here, the first complete genome sequence for C. carboxidivorans P7(T) is presented. This anaerobic bacterium harbors a 5,732,880bp circular chromosome and a 19,902bp mega-plasmid with 4951 and 22 coding DNA sequence (CDS), respectively. Copyright © 2015 Elsevier B.V. All rights reserved.

Read more
July 7, 2019

Complete genome sequence of Deinococcus soli N5(T), a gamma-radiation- resistant bacterium isolated from rice field in South Korea.

A Gram-negative, non-motile and short-rod shaped and gamma-radiation-resistant bacterium Deinococcus soli N5(T), isolated from a rice field soil in South Korea. The complete genome of D. soli N5(T) consists of a chromosome (3,236,984bp). The key enzymes for the central DNA repair mechanisms were present in the genome. The enzyme coding genes has been identified which is involving in the nucleotide excision repair (NER) pathway. The gene cluster in the genome sequence suggest that the D. soli N5(T) use (NER) pathways for efficient removal of pyrimidine dimers that are the most abundant type of UV- induced damage. Copyright © 2015 Elsevier B.V. All rights reserved.

Read more
July 7, 2019

Complete genome sequence of Piscirickettsia salmonis LF-89 (ATCC VR-1361) a major pathogen of farmed salmonid fish.

Piscirickettsia salmonis, the causative agent of salmonid rickettsial septicemia (SRS), is a significant threat to the healthy and sustainable production of salmonid farming industry. This Gram-negative bacterium, originally isolated from a coho salmon in Southern Chile, produces a systemic infection characterized by colonization of several fish organs. P. salmonis is able to infect, survive, and replicate inside salmonid macrophages however little is known about its mechanisms of pathogenesis. Here, we present the whole genome sequence and annotation of the P. salmonis reference strain LF-89 (ATCC VR-1361). The genome contains one circular chromosome of 3,184,851bp and three plasmids, pPSLF89-1 (180,124bp), pPSLF89-2 (33,516bp) and pPSLF89-3 (51,573bp). A total of 2850 protein-coding genes, 56 tRNAs and six copies of 5S-16S-23S rRNA. Copyright © 2015 Elsevier B.V. All rights reserved.

Read more
July 7, 2019

First complete genome sequence of Clostridium sporogenes DSM 795T, a nontoxigenic surrogate for Clostridium botulinum, determined using PacBio Single-Molecule Real-Time Technology.

The first complete genome sequence of Clostridium sporogenes DSM 795(T), a nontoxigenic surrogate for Clostridium botulinum, was determined in a single contig using the PacBio single-molecule real-time technology. The genome (4,142,990 bp; G+C content, 27.98%) included 86 sets of >1,000-bp identical sequence pairs and 380 tandem repeats. Copyright © 2015 Nakano et al.

Read more
July 7, 2019

The assembly and characterisation of two structurally distinct cattle MHC class I haplotypes point to the mechanisms driving diversity.

In cattle, there are six classical MHC class I genes that are variably present between different haplotypes. Almost all known haplotypes contain between one and three genes, with an allele of Gene 2 present on the vast majority. However, very little is known about the sequence and therefore structure and evolutionary history of this genomic region. To address this, we have refined the MHC class I region in the Hereford cattle genome assembly and sequenced a complete A14 haplotype from a homozygous Holstein. Comparison of the two haplotypes revealed extensive variation within the MHC class Ia region, but not within the flanking regions, with each gene contained within a conserved 63- to 68-kb sequence block. This variable region appears to have undergone block gene duplication and likely deletion at regular breakpoints, suggestive of a site-specific mechanism. Phylogenetic analysis using complete gene sequences provided evidence of allelic diversification via gene conversion, with breakpoints between each of the extracellular domains that were associated with high guanine-cytosine (GC) content. Advancing our knowledge of cattle MHC class I evolution will help inform investigations of cattle genetic diversity and disease resistance.

Read more
July 7, 2019

Draft genome sequence of Streptomyces sp. strain Wb2n-11, a desert isolate with broad-spectrum antagonism against soilborne phytopathogens.

Streptomyces sp. strain Wb2n-11, isolated from native desert soil, exhibited broad-spectrum antagonism against plant pathogenic fungi, bacteria, and nematodes. The 8.2-Mb draft genome reveals genes putatively responsible for its promising biocontrol activity and genes which enable the soil bacterium to directly interact beneficially with plants. Copyright © 2015 Köberl et al.

Read more
July 7, 2019

Whole-genome mapping as a novel high-resolution typing tool for Legionella pneumophila.

Legionella is the causative agent for Legionnaires’ disease (LD) and is responsible for several large outbreaks in the world. More than 90% of LD cases are caused by Legionella pneumophila, and studies on the origin and transmission routes of this pathogen rely on adequate molecular characterization of isolates. Current typing of L. pneumophila mainly depends on sequence-based typing (SBT). However, studies have shown that in some outbreak situations, SBT does not have sufficient discriminatory power to distinguish between related and nonrelated L. pneumophila isolates. In this study, we used a novel high-resolution typing technique, called whole-genome mapping (WGM), to differentiate between epidemiologically related and nonrelated L. pneumophila isolates. Assessment of the method by various validation experiments showed highly reproducible results, and WGM was able to confirm two well-documented Dutch L. pneumophila outbreaks. Comparison of whole-genome maps of the two outbreaks together with WGMs of epidemiologically nonrelated L. pneumophila isolates showed major differences between the maps, and WGM yielded a higher discriminatory power than SBT. In conclusion, WGM can be a valuable alternative to perform outbreak investigations of L. pneumophila in real time since the turnaround time from culture to comparison of the L. pneumophila maps is less than 24 h. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Read more
July 7, 2019

Essential roles of methionine and S-adenosylmethionine in the autarkic lifestyle of Mycobacterium tuberculosis.

Multidrug resistance, strong side effects, and compliance problems in TB chemotherapy mandate new ways to kill Mycobacterium tuberculosis (Mtb). Here we show that deletion of the gene encoding homoserine transacetylase (metA) inactivates methionine and S-adenosylmethionine (SAM) biosynthesis in Mtb and renders this pathogen exquisitely sensitive to killing in immunocompetent or immunocompromised mice, leading to rapid clearance from host tissues. Mtb ?metA is unable to proliferate in primary human macrophages, and in vitro starvation leads to extraordinarily rapid killing with no appearance of suppressor mutants. Cell death of Mtb ?metA is faster than that of other auxotrophic mutants (i.e., tryptophan, pantothenate, leucine, biotin), suggesting a particularly potent mechanism of killing. Time-course metabolomics showed complete depletion of intracellular methionine and SAM. SAM depletion was consistent with a significant decrease in methylation at the DNA level (measured by single-molecule real-time sequencing) and with the induction of several essential methyltransferases involved in biotin and menaquinone biosynthesis, both of which are vital biological processes and validated targets of antimycobacterial drugs. Mtb ?metA could be partially rescued by biotin supplementation, confirming a multitarget cell death mechanism. The work presented here uncovers a previously unidentified vulnerability of Mtb-the incapacity to scavenge intermediates of SAM and methionine biosynthesis from the host. This vulnerability unveils an entirely new drug target space with the promise of rapid killing of the tubercle bacillus by a new mechanism of action.

Read more
July 7, 2019

A multidrug resistance plasmid contains the molecular switch for type VI secretion in Acinetobacter baumannii.

Infections with Acinetobacter baumannii, one of the most troublesome and least studied multidrug-resistant superbugs, are increasing at alarming rates. A. baumannii encodes a type VI secretion system (T6SS), an antibacterial apparatus of Gram-negative bacteria used to kill competitors. Expression of the T6SS varies among different strains of A. baumannii, for which the regulatory mechanisms are unknown. Here, we show that several multidrug-resistant strains of A. baumannii harbor a large, self-transmissible resistance plasmid that carries the negative regulators for T6SS. T6SS activity is silenced in plasmid-containing, antibiotic-resistant cells, while part of the population undergoes frequent plasmid loss and activation of the T6SS. This activation results in T6SS-mediated killing of competing bacteria but renders A. baumannii susceptible to antibiotics. Our data show that a plasmid that has evolved to harbor antibiotic resistance genes plays a role in the differentiation of cells specialized in the elimination of competing bacteria.

Read more
July 7, 2019

Isolation and characterization of an interactive culture of two Paenibacillus species with moderately thermophilic desulfurization ability.

To isolate and characterize novel thermophilic bacteria capable of biodesulfurization of petroleum.A culture containing two Paenibacillus spp. (denoted “32O-W” and “32O-Y”) was isolated by repeated passage of a soil sample at up to 55 °C in medium containing dibenzothiophene (DBT) as sulfur source. Only 32O-Y metabolized DBT, apparently via the 4S pathway; maximum activity occurred from 40 to 45 °C, with some activity up to at least 50 °C. 32O-W enhanced DBT metabolism by 32O-Y (by 22-74 % at 40-50 °C). With sulfate as sulfur source, 32O-Y and 32O-W grew well up to 58 and 63 °C, respectively. Selection of a mixed culture of 32O-Y and 32O-W at 54 °C increased DBT metabolism 36-42 % from 40 to 45 °C. Genome sequencing identified desulfurization gene homologs in the strains consistent with their desulfurization properties.The 32O-Y/32O-W culture may be a useful starting point for development of an improved thermophilic petroleum biodesulfurization process.

Read more
July 7, 2019

Draft genome sequences of Burkholderia contaminans, a Burkholderia cepacia complex species that is increasingly recovered from cystic fibrosis patients.

Burkholderia contaminans belongs to the Burkholderia cepacia complex (BCC), a group of bacteria that are ubiquitous in the environment and capable of infecting the immunocompromised and people with cystic fibrosis. We report here draft genome sequences for the B. contaminans type strain LMG 23361 and an Argentinian cystic fibrosis sputum isolate. Copyright © 2015 Bloodworth et al.

Read more
July 7, 2019

Acetylcholinesterase 1 in populations of organophosphate-resistant North American strains of the cattle tick, Rhipicephalus microplus (Acari: Ixodidae).

Rhipicephalus microplus, the cattle fever tick, is a global economic problem to the cattle industry due to direct infestation of cattle and pathogens transmitted during feeding. Cattle fever tick outbreaks continue to occur along the Mexico-US border even though the tick has been eradicated from the USA. The organophosphate (OP) coumaphos targets acetylcholinesterase (AChE) and is the approved acaricide for eradicating cattle fever tick outbreaks. There is evidence for coumaphos resistance developing in cattle ticks in Mexico, and OP-resistant R. microplus ticks were discovered in outbreak populations of Texas in 2005. The molecular basis of coumaphos resistance is not known, and our study was established to gather further information on whether AChE1 is involved in the resistance mechanism. We also sought information on allele diversity in tick populations with different levels of coumaphos resistance. The overarching project goal was to define OP resistance-associated gene mutations such that a DNA-based diagnostic assay could be developed to assist the management of resistance. Three different AChE transcripts have been reported in R. microplus, and supporting genomic and transcriptomic data are available at CattleTickBase. Here, we report the complete R. microplus AChE1 gene ascertained by sequencing a bacterial artificial chromosome clone containing the entire coding region and the flanking 5′ and 3′ regions. We also report AChE1 sequences of larval ticks from R. microplus strains having different sensitivities to OP. To accomplish this, we sequenced a 669-bp region of the AChE1 gene corresponding to a 223 amino acid region of exon 2 to assess alleles in seven strains of R. microplus with varying OP resistance phenotypes. We identified 72 AChE1 sequence variants, 2 of which are strongly associated with OP-resistant phenotypes. Esterase-like sequences from the R. microplus transcriptome RmiTr Version 1.0 were compared to the available sequence databases to identify other transcripts with similarity to AChE1.

Read more

Subscribe for blog updates:

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.