1,369 research outputs found
The Goddess : Valse Hesitation
https://digitalcommons.library.umaine.edu/mmb-ps/2081/thumbnail.jp
Cloning and expression of a thermostable α-galactosidase from the thermophilic fungus Talaromyces emersonii in the methylotrophic yeast Pichia pastoris
The first gene (alpha-gal1) encoding an extracellular alpha-Dgalactosidase from the thermophilic fungus Talaromyces emersonii was cloned and characterized. The alpha-gal1 gene consisted of an open reading frame of 1,792 base pairs interrupted by six introns that encoded a mature protein of 452 amino acids, including a 24 amino acid secretory signal sequence. The translated protein had highest identity with other fungal alpha-galactosidases belonging to glycosyl hydrolase family 27. The alpha-gal1 gene was overexpressed as a secretory protein with an N-terminal histidine tag in the methylotrophic yeast Pichia pastoris. Recombinant alpha-Gal1 was secreted into the culture medium as a monomeric glycoprotein with a maximal yield of 10.75 mg/l and purified to homogeneity using Hisbinding nickel-agarose affinity chromatography. The purified enzyme was maximally active at 70 degrees C, pH 4.5, and lost no activity over 10 days at 50 degrees C. alpha-Gal1 followed Michaelis-Menten kinetics (Vmax of 240.3 micronM/min/mg, Km of 0.294 mM) and was inhibited competitively by galactose (Km obs of 0.57 mM, Ki of 2.77 mM). The recombinant T. emersonii alpha-galactosidase displayed broad substrate preference, being active on both oligo- and polymeric substrates, yet had strict specificity for the alpha-galactosidic linkage. Owing to its substrate preference and noteworthy stability, alpha-Gal1 is of particular interest for possible biotechnological applications involving the processing of plant materials.J.S. thanks her supervisor at the University of Jyvaskyla, Emily Knott, for permission to perform her Masters degree research while on exchange at NUT Galway, and for constructive comments on the manuscript. J.S. and A.G. both received scholarships under EU Erasmus/Socrates bilateral agreement. Funding for this research was provided in part to M.G.T. under the National Development Plan, through the Food Institutional Research Measure, administered by the Department of Agriculture, Fisheries and Food, Ireland
Sex Differences in the Behavioural Outcomes of Prenatal Nicotine and Tobacco Exposure
Smoking remains the leading cause of preventable death worldwide. A combination of biological and environmental risk factors make women especially vulnerable to nicotine addiction, making it harder for them to quit smoking. Smoking during pregnancy, therefore, is still a major health concern, with epidemiological data suggesting a role for gestational nicotine exposure in the development of several behavioural disorders. Given there are significant sex-specific behavioural outcomes related to smoking in adolescence and adulthood, it is probable that the behavioural outcomes following gestational nicotine or tobacco exposure are similarly sex-dependent. This is an especially relevant topic as the current landscape of nicotine use shifts toward vaping, a mode of high doses of nicotine delivery that is largely believed to be a safer alternative to cigarettes among the public as well as among pregnant women. Here we review existing clinical and preclinical findings regarding the sex-dependent behavioural outcomes of prenatal nicotine exposure. We also highlight the challenges within this literature, particularly those areas in which further research is necessary to improve consistency within, and between, clinical and preclinical findings
GNOMES II: Analysis of the Galactic diffuse molecular ISM in all four ground state hydroxyl transitions using Amoeba
We present observations of the four 2 Pi 3/2 J = 3/2 ground-rotational state
transitions of the hydroxyl molecule (OH) along 107 lines of sight both in and
out of the Galactic plane: 92 sets of observations from the Arecibo telescope
and 15 sets of observations from the Australia Telescope Compact Array (ATCA).
Our Arecibo observations included off-source pointings, allowing us to measure
excitation temperature (Tex) and optical depth, while our ATCA observations
give optical depth only. We perform Gaussian decomposition using the Automated
Molecular Excitation Bayesian line-fitting Algorithm 'AMOEBA' (Petzler, Dawson,
and Wardle 2021) fitting all four transitions simultaneously with shared
centroid velocity and width. We identify 109 features across 38 sightlines
(including 58 detections along 27 sightlines with excitation temperature
measurements). While the main lines at 1665 and 1667 MHz tend to have similar
excitation temperatures (median Tex(main) difference = 0.6 K, 84% show
Tex(main) difference < 2 K), large differences in the 1612 and 1720 MHz
satellite line excitation temperatures show that the gas is generally not in
LTE. For a selection of sightlines we compare our OH features to associated
(on-sky and in velocity) HI cold gas components (CNM) identified by Nguyen et
al. (2019) and find no strong correlations. We speculate that this may indicate
an effective decoupling of the molecular gas from the CNM once it accumulates.Comment: Accepted for publication to PASA. 41 pages, 27 figure
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