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Bacterial species belonging to the genus Pseudobutyrivibrio are important members of the rumen microbiome contributing to the degradation of complex plant polysaccharides. Pseudobutyrivibrio xylanivorans MA3014 was selected for genome sequencing to examine its ability to breakdown and utilize plant polysaccharides. The complete genome sequence of MA3014 is 3.58 Mb, consists of three replicons (a chromosome, chromid, and plasmid), has an overall G + C content of 39.6%, and encodes 3,265 putative protein-coding genes (CDS). Comparative pan-genomic analysis of all cultivated and currently available P. xylanivorans genomes has revealed a strong correlation of orthologous genes within this rumen bacterial species. MA3014 is metabolically versatile and capable of growing on a range of simple mono- or oligosaccharides derived from complex plant polysaccharides such as pectins, mannans, starch, and hemicelluloses, with lactate, butyrate, and formate as the principal fermentation end products. The genes encoding these metabolic pathways have been identified and MA3014 is predicted to encode an extensive range of Carbohydrate-Active enZYmes with 78 glycoside hydrolases, 13 carbohydrate esterases, and 54 glycosyl transferases, suggesting an important role in solubilization of plant matter in the rumen. [ABSTRACT FROM AUTHOR]

The author shares the key contact points around which he organized the Chartered Alternative Investment Analyst (CAIA) board's trip to Asia. He states that the entire CAIA team is committed to working for its members and announces their plans of making an official launch for a China Member Chapter in 2014. He stresses the importance of academic partnerships. The author also mentions his involvement in press interviews and media outreach during the trip.

Hydrogen (H2) is the primary electron donor for methane formation in ruminants, but the H2-producing organisms involved are largely uncharacterized. This work integrated studies of microbial physiology and genomics to characterize rumen bacterial isolate NK3A20 of the family Lachnospiraceae. Isolate NK3A20 was the first recognized isolate of the NK3A20 group, which is among the ten most abundant bacterial genera in 16S rRNA gene surveys of rumen microbiota. NK3A20 produced acetate, butyrate, H2, and formate from glucose. The end product ratios varied when grown with different substrates and at different H2 partial pressures. NK3A20 produced butyrate as a major product using glucose or under high H2 partial pressures and switched to mainly acetate in the presence of galacturonic acid (an oxidized sugar) or in coculture with a methanogen. Growth with galacturonic acid was faster at elevated H2 concentrations, while elevated H2 slowed growth with glucose. Genome analyses revealed the presence of multiple hydrogenases including a membrane-bound Ech hydrogenase, an electron bifurcating butyryl-CoA dehydrogenase (Bcd-Etf), and an Rnf complex that may be involved in modulating the observed metabolic pathway changes, providing insight into H2 formation in the rumen. [ABSTRACT FROM AUTHOR]

In the article, the author discusses developments in the investment management business, particularly in the U.S., as of January 2015. He focuses on the liquid alternatives investments, which were created mainly to avoid drawdowns and attain broad diversification in various uncorrelated risks. He claims that the performance of such alternatives in situations like the global financial crisis in 2008 is yet to be tested.

It is known that process scaling-up has always been a challenge in biopharmaceutical and food industry. In recent years, newly emerging microscale bioreactors like Ambr15 and Ambr250 have attracted significant attention for that they can provide high throughput and accelerate upstream process development. In this work, we developed the first multiphase Computational Fluid Dynamics (CFD) model for an in-depth characterization of Ambr bioreactor systems. A number of advanced computational methods, including Reynolds stress turbulence model, population balance model, multiple reference frame (MRF), sliding mesh (SM) and user defined functions (UDFs), were integrated for the first time to systematically study the gas-liquid mixing in Ambr250 bioreactor. We provided detailed comparison between MRF and SM method, demonstrated the limitation of MRF for predicting bubble distribution in asymmetric reactors. Characteristics of hydrodynamics, mass transfer, turbulent dissipation and bubble size distribution were predicted from our CFD models and validated by existing experimental data for a variety of operating conditions for both the Ambr15 and Ambr250 bioreactors. The predicted kLa value ranges are 0.18-7.90 h-1 and 2.15-11.52 h-1 for Ambr250 and Ambr15, respectively. This work thus provides a superior framework for the computational modeling of microscale stirred bioreactors. [ABSTRACT FROM AUTHOR]

Pectin is a complex polysaccharide that forms a substantial proportion of the plant's middle lamella of forage ingested by grazing ruminants. Methanol in the rumen is derived mainly from methoxy groups released from pectin by the action of pectin methylesterase (PME) and is subsequently used by rumen methylotrophic methanogens that reduce methanol to produce methane (CH4). Members of the genus Butyrivibrio are key pectin-degrading rumen bacteria that contribute to methanol formation and have important roles in fibre breakdown, protein digestion, and the biohydrogenation of fatty acids. Therefore, methanol release from pectin degradation in the rumen is a potential target for CH4 mitigation technologies. Here, we present the crystal structures of PMEs belonging to the carbohydrate esterase family 8 (CE8) from Butyrivibrio proteoclasticus and Butyrivibrio fibrisolvens, determined to a resolution of 2.30 Å. These enzymes, like other PMEs, are right-handed β-helical proteins with a well-defined catalytic site and reaction mechanisms previously defined in insect, plant, and other bacterial pectin methylesterases. Potential substrate binding domains are also defined for the enzymes. [ABSTRACT FROM AUTHOR]

Simple Summary: T cell-based therapies can be costly, inconsistent, and differentially effective for patients. The limiting reagent for T cell-based immunotherapies is the T cell itself. T cell growth has been linked to endogenously delivered cytokines and messenger proteins that indicate the status of inflammation of the local system in the body. IL-2, IL-7, and IL-15 are the specific cytokines that have been identified in combination to deliver accelerated growth to different T cell subsets. This study focuses on the growth of T cell subsets subject to different combinations of IL-2, IL-7, and IL-15 in the experiment. Based on growth data, mathematical models were developed to project the optimal growth conditions for CD4+ and CD8+ Naïve and Memory T Cells. RNA sequence data is finally analyzed to study the gene networks that influence growth pathways, specifically for CD4+ and CD8+ naïve and memory subsets. The growth of T cells ex vivo for the purpose of T cell therapies is a rate-limiting step in the overall process for cancer patients to achieve remission. Growing T cells is a fiscally-, time-, and resource-intensive process. Cytokines have been shown to accelerate the growth of T cells, specifically IL-2, IL-7, and IL-15. Here a design of experiments was conducted to optimize the growth rate of different naïve and memory T cell subsets using combinations of cytokines. Mathematical models were developed to study the impact of IL-2, IL-7, and IL-15 on the growth of T cells. The results show that CD4+ and CD8+ naïve T cells grew effectively using moderate IL-2 and IL-7 in combination, and IL-7, respectively. CD4+ and CD8+ memory cells favored moderate IL-2 and IL-15 in combination and moderate IL-7 and IL-15 in combination, respectively. A statistically significant interaction was observed between IL-2 and IL-7 in the growth data of CD4+ naïve T cells, while the interaction between IL-7 and IL-15 was found for CD8+ naïve T cells. The important genes and related signaling pathways and metabolic reactions were identified from the RNA sequencing data for each of the four subsets stimulated by each of the three cytokines. This systematic investigation lays the groundwork for studying other T cell subsets. [ABSTRACT FROM AUTHOR]

Disposal of electrons generated during the fermentation of ingested feed is a fundamental feature of anaerobic microbial gut ecosystems. Here, we focus on the well-studied rumen environment to highlight how electrons are transferred through anaerobic fermentation pathways and how manipulating this electron flow is important to reducing methane emissions from ruminants. Priorities for research that can accelerate understanding in this area are highlighted. [ABSTRACT FROM AUTHOR]

PCR primers were designed to amplify the gene that encodes bovicin 255 from Streptococcus gallolyticus LRC0255 and the bacteriocin genes from Butyrivibrio fibrisolvens strains AR10 and OR79A (bviD and bvi79A) in order to screen for their incidence in rumen and caecal B. fibrisolvens and Streptococcus bovis-like isolates from New Zealand and North American ruminants. None of the B. fibrisolvens-like strains (n=34) isolated from New Zealand or North America had the genes encoding for butyrivibriocins AR10 (bviD) or OR79 (bvi79A). However, seven S. bovis isolates from New Zealand ruminants and three from North American animals had the bovicin 255 gene. Sequence comparison of cloned bovicin 255 PCR products indicated a 92.9–95.7% similarity to that of the corresponding bovicin 255 gene sequence of S. gallolyticus. Four of the New Zealand bovicin 255 positive S. bovis isolates were from the caecal contents of the same sheep and had identical PFGE profiles. Two other S. bovis isolates sharing the same PFGE profile were isolated from a separate animal from the same flock. PFGE analysis of the North American strains indicated that all three were closely related as two of three had identical PFGE profiles with the remaining isolate differing only by a single band position. The 16S rRNA gene sequences of the 10 isolates were at least 99.8% identical to S. bovis. All 10 S. bovis isolates having the gene for bovicin 255 produced bacteriocin activity that inhibited the growth of Peptostreptococcus anaerobius D1 in a deferred antagonism plating (DAP) assay. Certain S. bovis isolates obtained from ruminants have bacteriocin activity associated with a distinct bovicin 255 gene sequence but it appears that bacteriocin production by the rumen anaerobe B. fibrisolvens may be uncommon in strains isolated from cattle and sheep in New Zealand. [Copyright &y& Elsevier]