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151.
The in vitro metabolism of pregnenolone by two Bacillus strains (HA-V6-3 and HA-V6-11) isolated from the foregut of the water beetle Agabus affinis (Payk.) was examined in the course of our studies about a possible participation of gut micro-organisms in the biosynthesis of prothoracic defensive steroids of dytiscids. The transformation products were identified by EI GC--MS of culture extracts after derivatization. The dominating reactions were hydroxylations, with 7 alpha-hydroxypregnenolone as the major product. With considerably lower yields, 7 beta- and 15xi-hydroxypregenolone were formed by both strains, while 11, 17 and 16 alpha-hydroxypregnenolone were produced only by HA-V6-3. The occurrence of 7, 11 alpha- and 7 beta, 11 alpha-dihydroxypregnenolone as well as several minor products containing a 17 alpha-OH group proved the capability of HA-V6-11 to hydroxylate pregenenolone at C(11) and C(17) as well. The monohydroxylated 7-OH-pregnenolones were partly oxidized to 7-oxopregnenolone by both strains. In trace amounts, HA-V6-3 performed 3 beta-acetylation of pregnenolone. 相似文献
152.
Stable-isotope-labelled (2H6,18O) 3-hydroxy-3-phenylpropanoic acid, a putative intermediate in the biosynthesis of benzoic acid (BA) and salicylic acid (SA)
from cinnamic acid, has been synthesized and administered to cucumber (Cucumis sativus L.) and Nicotiana attenuata (Torrey). Analysis of the products by gas chromatography-mass spectrometry revealed incorporation of labelling into BA and
SA, but not into benzaldehyde. In a separate experiment, 3-hydroxy- 3-phenylpropanoic acid was found to be a metabolite of
phenylalanine, itself the primary metabolic precursor of BA and SA. These data suggest that cinnamic acid chain shortening
is probably achieved by β-oxidation, and that the proposed “non-oxidative” pathway of side-chain degradation does not function
in the biosynthesis of BA and SA, in cucumber and N. attenuata.
Received: 10 February 2000 / Accepted: 18 April 2000 相似文献
153.
Alejandro A. Schaaf 《Bird Study》2019,66(4):561-564
ABSTRACTThe orientation of the nest entrances of 464 nests of the Rufous Hornero Furnarius rufus were explored in relation to vegetation cover along an altitudinal gradient in Argentina. There was no correlation between altitude and orientation for covered nests, since they were well protected from direct solar radiation, however, uncovered nests were orientated more towards the north with increasing altitude, probably to take advantage of warming solar radiation at colder, higher altitudes. 相似文献
154.
Germana B Rona Natalia P Almeida Gilson C Santos Jr Tatiana KS Fidalgo Fabio CL Almeida Elis CA Eleutherio Anderson S Pinheiro 《Journal of cellular biochemistry》2019,120(4):5377-5385
NSD3s, the proline-tryptophan-tryptophan-proline (PWWP) domain-containing, short isoform of the human oncoprotein NSD3, displays high transforming properties. Overexpression of human NSD3s or the yeast protein Pdp3 in Saccharomyces cerevisiae induces similar metabolic changes, including increased growth rate and sensitivity to oxidative stress, accompanied by decreased oxygen consumption. Here, we set out to elucidate the biochemical pathways leading to the observed metabolic phenotype by analyzing the alterations in yeast metabolome in response to NSD3s or Pdp3 overexpression using 1H nuclear magnetic resonance (NMR) metabolomics. We observed an increase in aspartate and alanine, together with a decrease in arginine levels, on overexpression of NSD3s or Pdp3, suggesting an increase in the rate of glutaminolysis. In addition, certain metabolites, including glutamate, valine, and phosphocholine were either NSD3s or Pdp3 specific, indicating that additional metabolic pathways are adapted in a protein-dependent manner. The observation that certain metabolic pathways are differentially regulated by NSD3s and Pdp3 suggests that, despite the structural similarity between their PWWP domains, the two proteins act by unique mechanisms and may recruit different downstream signaling complexes. This study establishes for the first time a functional link between the human oncoprotein NSD3s and cancer metabolic reprogramming. 相似文献
155.
Sessink OD van der Schaaf H Beeftink HH Hartog RJ Tramper J 《Trends in biotechnology》2007,25(1):16-23
The combination of web technology, knowledge of bioprocess engineering, and theories on learning and instruction might yield innovative learning material for bioprocess engineering. In this article, an overview of the characteristics of web-based learning material is given, as well as guidelines for the design of learning material from theories of learning and instruction and from the bioprocess engineering domain. A diverse body of learning material is presented, which illustrates the application of these guidelines; this material has been developed during the past six years for different courses, mostly at undergraduate level, and it illustrates how web-based learning material can enable various different approaches to learning objectives that might improve overall learning. Such learning material has been used for several years in education, it has been evaluated with positive results, and is now part of the regular learning material for bioprocess engineering at Wageningen University. 相似文献
156.
Natália Spitz Francisco CA Mello Natalia Motta Araujo 《Memórias do Instituto Oswaldo Cruz》2015,110(1):151-153
The Brazilian Amazon Region is a highly endemic area for hepatitis B virus (HBV).
However, little is known regarding the genetic variability of the strains circulating
in this geographical region. Here, we describe the first full-length genomes of HBV
isolated in the Brazilian Amazon Region; these genomes are also the first complete
HBV subgenotype D3 genomes reported for Brazil. The genomes of the five Brazilian
isolates were all 3,182 base pairs in length and the isolates were classified as
belonging to subgenotype D3, subtypes ayw2 (n = 3) and ayw3 (n = 2). Phylogenetic
analysis suggested that the Brazilian sequences are not likely to be closely related
to European D3 sequences. Such results will contribute to further epidemiological and
evolutionary studies of HBV. 相似文献
157.
RG Lockie AB Schultz SJ Callaghan CA Jordan TM Luczo MD Jeffriess 《Biology of sport / Institute of Sport》2015,32(1):41-51
There is little research investigating relationships between the Functional Movement Screen (FMS) and athletic performance in female athletes. This study analyzed the relationships between FMS (deep squat; hurdle step [HS]; in-line lunge [ILL]; shoulder mobility; active straight-leg raise [ASLR]; trunk stability push-up; rotary stability) scores, and performance tests (bilateral and unilateral sit-and-reach [flexibility]; 20-m sprint [linear speed]; 505 with turns from each leg; modified T-test with movement to left and right [change-of-direction speed]; bilateral and unilateral vertical and standing broad jumps; lateral jumps [leg power]). Nine healthy female recreational team sport athletes (age = 22.67 ± 5.12 years; height = 1.66 ± 0.05 m; body mass = 64.22 ± 4.44 kilograms) were screened in the FMS and completed the afore-mentioned tests. Percentage between-leg differences in unilateral sit-and-reach, 505 turns and the jumps, and difference between the T-test conditions, were also calculated. Spearman''s correlations (p ≤ 0.05) examined relationships between the FMS and performance tests. Stepwise multiple regressions (p ≤ 0.05) were conducted for the performance tests to determine FMS predictors. Unilateral sit-and-reach positive correlated with the left-leg ASLR (r = 0.704-0.725). However, higher-scoring HS, ILL, and ASLR related to poorer 505 and T-test performance (r = 0.722-0.829). A higher-scored left-leg ASLR related to a poorer unilateral vertical and standing broad jump, which were the only significant relationships for jump performance. Predictive data tended to confirm the correlations. The results suggest limitations in using the FMS to identify movement deficiencies that could negatively impact athletic performance in female team sport athletes. 相似文献
158.
Hierarchical folding and reorganization of chromosomes are linked to transcriptional changes in cellular differentiation
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Mariano Barbieri Benjamin L Moore Dorothee CA Kraemer Stuart Aitken Sheila Q Xie Kelly J Morris Masayoshi Itoh Hideya Kawaji Ines Jaeger Yoshihide Hayashizaki Piero Carninci Alistair RR Forrest The FANTOM Consortium Colin A Semple Josée Dostie Ana Pombo Mario Nicodemi 《Molecular systems biology》2015,11(12)
159.
Saman Rasoul Jan Paul Ottervanger Jan-Henk E Dambrink Menko-Jan de Boer Jan CA Hoorntje AT Marcel Gosselink Felix Zijlstra Harry Suryapranata Arnoud WJ van't Hof 《BMC cardiovascular disorders》2007,7(1):1-7
Background
We have previously documented significant differences in orthogonal P wave morphology between patients with and without paroxysmal atrial fibrillation (PAF). However, there exists little data concerning normal P wave morphology. This study was aimed at exploring orthogonal P wave morphology and its variations in healthy subjects.Methods
120 healthy volunteers were included, evenly distributed in decades from 20–80 years of age; 60 men (age 50+/-17) and 60 women (50+/-16). Six-minute long 12-lead ECG registrations were acquired and transformed into orthogonal leads. Using a previously described P wave triggered P wave signal averaging method we were able to compare similarities and differences in P wave morphologies.Results
Orthogonal P wave morphology in healthy individuals was predominately positive in Leads X and Y. In Lead Z, one third had negative morphology and two-thirds a biphasic one with a transition from negative to positive. The latter P wave morphology type was significantly more common after the age of 50 (P < 0.01). P wave duration (PWD) increased with age being slightly longer in subjects older than 50 (121+/-13 ms vs. 128+/-12 ms, P < 0.005). Minimal intraindividual variation of P wave morphology was observed.Conclusion
Changes of signal averaged orthogonal P wave morphology (biphasic signal in Lead Z), earlier reported in PAF patients, are common in healthy subjects and appear predominantly after the age of 50. Subtle age-related prolongation of PWD is unlikely to be sufficient as a sole explanation of this finding that is thought to represent interatrial conduction disturbances. To serve as future reference, P wave morphology parameters of the healthy subjects are provided. 相似文献160.
Hedley CA Emsley Craig J Smith Carole M Gavin Rachel F Georgiou Andy Vail Elisa M Barberan Karen Illingworth Sylvia Scarth Vijitha Wickramasinghe Margaret E Hoadley Nancy J Rothwell Pippa J Tyrrell Stephen J Hopkins 《BMC neurology》2007,7(1):1-12