Characterization of Emetic Bacillus weihenstephanensis, a New Cereulide-Producing Bacterium

Cereulide production has until now been restricted to the species Bacillus cereus. Here we report on two psychrotolerant Bacillus weihenstephanensis strains, MC67 and MC118, that produce cereulide. The strains are atypical with regard to pheno- and genotypic characteristics normally used for identification of emetic B. cereus strains. MC67 and MC118 produced cereulide at temperatures of as low as 8°C.     

(3)H]-M-MPEP, a potent, subtype-selective radioligand for the metabotropic glutamate receptor subtype 5

The synthesis of a new potent, subtype-selective radioligand [(3)H]-M-MPEP (2-methyl-6-((3-methoxyphenyl)ethynyl)-pyridine) and its in vitro pharmacological characteristics are described. Science Ltd.     

Improving genome assemblies by sequencing PCR products with PacBio

Advances in sequencing technologies have dramatically reduced costs in producing high-quality draft genomes. However, there are still many contigs and possible misassembled regions in those draft genomes. Improving the quality of these genomes requires an efficient and economical means to close gaps and resequence some regions. Sequencing pooled gap region PCR products with Pacific Biosciences (PacBio) provides a significantly less expensive means for this need. We have developed a genome improvement pipeline with this strategy after decreasing a loading bias against larger PCR products in the PacBio process. Compared with Sanger technology, this approach is not only cost-effective but also can close gaps greater than 2.5 kb in a single round of reactions, and sequence through high GC regions as well as difficult secondary structures such as small hairpin loops.     

British Columbia’s Fish Health Regulatory Framework’s Contribution to Sustainability Goals Related to Salmon Aquaculture

Salmon farming is a significant contribution to the global seafood market to which the goal of sustainability is often applied. Diseases related to farms are perhaps the most contentious issues associated with sustainable salmon farming. We reviewed literature and policies in British Columbia, Canada, as well as interviewed key informants to examine how fish health regulations do or could support sustainability goals. We found four main obstacles to the development and application of a sustainability-based health management system. First, salmon farming faced the same challenges as other industries when trying to establish an operational definition of sustainability that captures all stakeholders’ interests. Second, there was no program responsible for integrating the various regulations, responsible departments, and monitoring efforts to develop a comprehensive view of sustainability. Third, there was inadequate research base and social consensus on the criteria that should be used to track health outcomes for sustainability purposes. Fourth, the regulatory and management paradigm for salmon farming has been focused on diseases and pathogens as opposed to embracing a more inclusive health promotion model that includes biotic, abiotic, and social determinants of health. A transparent and inclusive participatory process that effectively links expert views with community and industry concerns should serve as the foundation for the next generation of health management regulations for salmon farming.     

Hepatic uptake and metabolism of galactose can be quantified in vivo by 2-[18F]fluoro-2-deoxygalactose positron emission tomography

Metabolism of galactose is a specialized liver function. The purpose of this PET study was to use the galactose analog 2-[(18)F]fluoro-2-deoxygalactose (FDGal) to investigate hepatic uptake and metabolism of galactose in vivo. FDGal kinetics was studied in 10 anesthetized pigs at blood concentrations of nonradioactive galactose yielding approximately first-order kinetics (tracer only; n = 4), intermediate kinetics (0.5-0.6 mmol galactose/l blood; n = 2), and near-saturation kinetics (>3 mmol galactose/l blood; n = 4). All animals underwent liver C15O PET (blood volume) and FDGal PET (galactose kinetics) with arterial and portal venous blood sampling. Flow rates in the hepatic artery and the portal vein were measured by ultrasound transit-time flowmeters. The hepatic uptake and net metabolic clearance of FDGal were quantified by nonlinear and linear regression analyses. The initial extraction fraction of FDGal from blood-to-hepatocyte was unity in all pigs. Hepatic net metabolic clearance of FDGal, K(FDGal), was 332-481 ml blood.min(-1).l(-1) tissue in experiments with approximately first-order kinetics and 15.2-21.8 ml blood.min(-1).l(-1) tissue in experiments with near-saturation kinetics. Maximal hepatic removal rates of galactose were on average 600 micromol.min(-1).l(-1) tissue (range 412-702), which was in agreement with other studies. There was no significant difference between K(FDGal) calculated with use of the dual tracer input (Kdual(FDGal)) or the single arterial input (Karterial(FDGal)). In conclusion, hepatic galactose kinetics can be quantified with the galactose analog FDGal. At near-saturated kinetics, the maximal hepatic removal rate of galactose can be calculated from the net metabolic clearance of FDGal and the blood concentration of galactose.     

The Genome of Polaromonas sp. Strain JS666: Insights into the Evolution of a Hydrocarbon- and Xenobiotic-Degrading Bacterium, and Features of Relevance to Biotechnology

Polaromonas sp. strain JS666 can grow on cis-1,2-dichloroethene (cDCE) as a sole carbon and energy source and may be useful for bioremediation of chlorinated solvent-contaminated sites. Analysis of the genome sequence of JS666 (5.9 Mb) shows a bacterium well adapted to pollution that carries many genes likely to be involved in hydrocarbon and xenobiotic catabolism and metal resistance. Clusters of genes coding for haloalkane, haloalkanoate, n-alkane, alicyclic acid, cyclic alcohol, and aromatic catabolism were analyzed in detail, and growth on acetate, catechol, chloroacetate, cyclohexane carboxylate, cyclohexanol, ferulate, heptane, 3-hydroxybenzoate, hydroxyquinol, gentisate, octane, protocatechuate, and salicylate was confirmed experimentally. Strain JS666 also harbors diverse putative mobile genetic elements, including retrons, inteins, a miniature inverted-repeat transposable element, insertion sequence transposases from 14 families, eight genomic islands, a Mu family bacteriophage, and two large (338- and 360-kb) plasmids. Both plasmids are likely to be self-transferable and carry genes for alkane, alcohol, aromatic, and haloacid metabolism. Overall, the JS666 genome sequence provides insights into the evolution of pollutant-degrading bacteria and provides a toolbox of catabolic genes with utility for biotechnology.     

Age,growth and radiometric age validation of a deep-sea,habitat-forming gorgonian (Primnoa resedaeformis) from the Gulf of Alaska

Sustainable fisheries require (1) viable stock populations with appropriate harvest limits and (2) appropriate habitat for fish to survive, forage, seek refuge, grow and reproduce. Some deep-water habitats, such as those formed by deep-water stands of coral, may be vulnerable to fishing disturbance. The rate at which habitat can be restored is a critical aspect of fishery management. The purpose of this study was to characterize growth rates for a habitat-forming deep-sea coral. Two nearly complete colonies of red tree coral (Primnoa resedaeformis) collected from waters off southeast Alaska were used for an analysis of age and growth characteristics. CAT scans revealed that colonies consisted of multiple settlement events, where older basal structures provided for settlement of new colonies. The decay of ²¹⁰Pb over the length of the colony was used to validate age estimates from growth ring counts. Age estimates were over 100 yr for sections near the heavily calcified base. Based on validated growth ring counts, growth of red tree coral ranged from 1.60 to 2.32 cm per year in height and was approximately 0.36 mm per year in diameter. These growth rates suggest that the fishery habitat created by red tree coral is extremely vulnerable to bottom fishing activities and may take over 100 years to recover.