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21.
Taste preferences of four classic taste substances (NaCl, CaCl2, and sucrose, all—10%; and citric acid—5%), and 21 free amino acids (L-isomers, 0.1–0.001 M) for adult threespine stickebacks
Gasterosteus aculeatus is determined in marine and fresh waters. Gustatory responses were compared in the fish caught in marine and placed in marine
water or in freshwater and in the fish caught in a stream mouth during spawning migration and in a closed freshwater water
body. Taste preferences of threespine sticklebacks depend little on water salinity. Of amino acids, cysteine, glutamic acid,
and aspartic acid are attractive, as well as glutamine for the fish living permanently in fresh water. Differences in the
reaction of fish to agar-agar pellets with NaCl, CaCl2, and sucrose are considered to be insignificant. Maximum changes occur in the attitude of threespine sticklebacks to citric
acid whose taste is palatable to fish in fresh water. It is assumed that the components of marine water render a modifying
action on gustatory receptors, the function of receptor cell, and influence susceptibility of fish to the taste of citric
acid and, probably, of some other substances. The foraging behavior of fish in fresh water is more active, they consume more
pellets, make more numerous repeated grasps, and keep pellets longer in the mouth cavity before swallowing or rejection. It
is concluded that, in migratory fish, the abrupt change of external osmotic conditions is not accompanied by noticeable changes
on taste preferences and the majority of substances retain their gustatory properties. 相似文献
22.
Carmen Martínez José A Molina Hortensia Alonso-Navarro Félix J Jiménez-Jiménez José AG Agúndez Elena García-Martín 《BMC neurology》2010,10(1):71
Background
Human serum paraoxonase 1 (PON1) plays a major role in the metabolism of several organophosphorus compounds. The enzyme is encoded by the polymorphic gene PON1, located on chromosome 7q21.3. Aiming to identify genetic variations related to the risk of developing brain tumors, we investigated the putative association between common nonsynonymous PON1 polymorphisms and the risk of developing astrocytoma and meningioma. 相似文献23.
Mikhailova MV Mayeux PR Jurkevich A Kuenzel WJ Madison F Periasamy A Chen Y Cornett LE 《Molecular endocrinology (Baltimore, Md.)》2007,21(9):2178-2188
In birds, ACTH release from the anterior pituitary gland during stress is controlled by CRH and arginine vasotocin (AVT). Using 5-wk-old male chicks, simultaneous iv injections of CRH and AVT were found to result in a greater than additive increase in plasma corticosterone levels compared with that obtained with individual administration of either peptide hormone. In order to investigate molecular mechanisms underlying this observation, the chicken CRH receptor (CRHR) and vasotocin VT2 receptor (VT2R) were fused to cyan and yellow fluorescent proteins and expressed in HeLa cells. The resulting CRHR and VT2R fusion proteins were expressed appropriately in the plasma membrane and were found to couple to downstream signal transduction pathways. Quantitative fluorescence resonance energy transfer (FRET) analysis was used to determine whether the CRHR and VT2R formed heterodimers. In the absence of CRH and AVT, the FRET efficiency was 15-18%, and the distance between receptors was 5-6 nm. Treatment of the cells that expressed both cyan fluorescent protein-CRHR and yellow fluorescent protein-VT2R with CRH or AVT alone did not lead to a significant change in the FRET efficiency. However, simultaneous addition of these hormones increased the efficiency of the FRET signal and decreased the distance between the two receptors. In HeLa cells expressing both CRHR and VT2R, treatment with CRH and AVT resulted in a significant increase in cAMP production over that with CRH alone, indicating that heterodimer formation may enhance the ability of the CRHR to activate downstream signal transduction. 相似文献
24.
Comparative substrate analysis of full-length bovine enteropeptidase and trypsin, bovine and human enteropeptidase light chains was performed using model N-terminal dodecapeptides corresponding to wild-type human trypsinogen and pancreatitis-associated mutant trypsinogens K23R and D22G. The substitution of Lys residue by Arg at P1 leads to 2-fold increase in the efficiency of enteropeptidase hydrolysis; the absence of the negatively charged residue at P2 reduces the efficiency of such hydrolysis by two orders of magnitude. The difference in efficiency of peptide chain hydrolysis after Lys/Arg residues by enteropeptidase compared to trypsin is equal to the difference in hydrolysis by serine proteases of different primary specificity of their specific substrates. 相似文献
25.
Denis Susorov Tatiana Mikhailova Alexander Ivanov Elizaveta Sokolova Elena Alkalaeva 《Nucleic acids research》2015,43(6):3332-3343
Stabilization of the ribosomal complexes plays an important role in translational control. Mechanisms of ribosome stabilization have been studied in detail for initiation and elongation of eukaryotic translation, but almost nothing is known about stabilization of eukaryotic termination ribosomal complexes. Here, we present one of the mechanisms of fine-tuning of the translation termination process in eukaryotes. We show that certain deacylated tRNAs, remaining in the E site of the ribosome at the end of the elongation cycle, increase the stability of the termination and posttermination complexes. Moreover, only the part of eRF1 recognizing the stop codon is stabilized in the A site of the ribosome, and the stabilization is not dependent on the hydrolysis of peptidyl-tRNA. The determinants, defining this property of the tRNA, reside in the acceptor stem. It was demonstrated by site-directed mutagenesis of tRNAVal and construction of a mini-helix structure identical to the acceptor stem of tRNA. The mechanism of this stabilization is different from the fixation of the unrotated state of the ribosome by CCA end of tRNA or by cycloheximide in the E site. Our data allow to reveal the possible functions of the isodecoder tRNAs in eukaryotes. 相似文献
26.
JI Priego AG Lucas-Cuevas I Aparicio JV Giménez JM Cortell-Tormo P Pérez-Soriano 《Biology of sport / Institute of Sport》2015,32(3):219-223
The use of graduated compression stockings (GCS) in sport has been increasing in the last years due to their potential positive effects for athletes. However, there is little evidence to support whether these types of garments actually improve cardiorespiratory performance. The aim of this study was to examine the cardiorespiratory responses of GCS during running after three weeks of regular use. Twenty recreational runners performed three tests on different days: test 1) – a 5-min maximal effort run in order to determine the participants’ maximal aerobic speed; and tests 2) and 3) – a fatigue running test of 30 minutes at 80% of their maximal aerobic speed with either GCS or PLACEBO stockings at random. Cardiorespiratory parameters (minute ventilation, heart rate, relative oxygen consumption, relative carbon dioxide production, ventilatory equivalents for oxygen and carbon dioxide, and oxygen pulse) were measured. Before each test in the laboratory, the participants trained with the randomly assigned stockings (GCS or PLACEBO) for three weeks. No significant differences between GCS and PLACEBO were found in any of the cardiorespiratory parameters. In conclusion, the present study provides evidence that running with GCS for three weeks does not influence cardiorespiratory parameters in recreational runners. 相似文献
27.
Chertkov O Sikorski J Nolan M Lapidus A Lucas S Del Rio TG Tice H Cheng JF Goodwin L Pitluck S Liolios K Ivanova N Mavromatis K Mikhailova N Ovchinnikova G Pati A Chen A Palaniappan K Djao OD Land M Hauser L Chang YJ Jeffries CD Brettin T Han C Detter JC Rohde M Göker M Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Klenk HP Kyrpides NC 《Standards in genomic sciences》2011,4(1):13-22
Thermomonospora curvata Henssen 1957 is the type species of the genus Thermomonospora. This genus is of interest because members of this clade are sources of new antibiotics, enzymes, and products with pharmacological activity. In addition, members of this genus participate in the active degradation of cellulose. This is the first complete genome sequence of a member of the family Thermomonosporaceae. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 5,639,016 bp long genome with its 4,985 protein-coding and 76 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
28.
Zeytun A Sikorski J Nolan M Lapidus A Lucas S Han J Tice H Cheng JF Tapia R Goodwin L Pitluck S Liolios K Ivanova N Mavromatis K Mikhailova N Ovchinnikova G Pati A Chen A Palaniappan K Ngatchou-Djao OD Land M Hauser L Jeffries CD Han C Detter JC Ubler S Rohde M Tindall BJ Göker M Wirth R Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Klenk HP Kyrpides NC 《Standards in genomic sciences》2011,4(2):131-143
Hydrogenobacter thermophilus Kawasumi et al. 1984 is the type species of the genus Hydrogenobacter. H. thermophilus was the first obligate autotrophic organism reported among aerobic hydrogen-oxidizing bacteria. Strain TK-6(T) is of interest because of the unusually efficient hydrogen-oxidizing ability of this strain, which results in a faster generation time compared to other autotrophs. It is also able to grow anaerobically using nitrate as an electron acceptor when molecular hydrogen is used as the energy source, and able to aerobically fix CO(2)via the reductive tricarboxylic acid cycle. This is the fifth completed genome sequence in the family Aquificaceae, and the second genome sequence determined from a strain derived from the original isolate. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 1,742,932 bp long genome with its 1,899 protein-coding and 49 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
29.
Pati A Gronow S Lu M Lapidus A Nolan M Lucas S Hammon N Deshpande S Cheng JF Tapia R Han C Goodwin L Pitluck S Liolios K Pagani I Mavromatis K Mikhailova N Huntemann M Chen A Palaniappan K Land M Hauser L Detter JC Brambilla EM Rohde M Göker M Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Ivanova N 《Standards in genomic sciences》2011,5(1):41-49
Prevotella multisaccharivorax Sakamoto et al. 2005 is a species of the large genus Prevotella, which belongs to the family Prevotellaceae. The species is of medical interest because its members are able to cause diseases in the human oral cavity such as periodontitis, root caries and others. Although 77 Prevotella genomes have already been sequenced or are targeted for sequencing, this is only the second completed genome sequence of a type strain of a species within the genus Prevotella to be published. The 3,388,644 bp long genome is assembled in three non-contiguous contigs, harbors 2,876 protein-coding and 75 RNA genes and is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
30.
Lang E Teshima H Lucas S Lapidus A Hammon N Deshpande S Nolan M Cheng JF Pitluck S Liolios K Pagani I Mikhailova N Ivanova N Mavromatis K Pati A Tapia R Han C Goodwin L Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Brambilla EM Kopitz M Rohde M Göker M Tindall BJ Detter JC Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Klenk HP Kyrpides NC 《Standards in genomic sciences》2011,4(1):81-90