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21.
L S Fang M S Hung 《Comparative biochemistry and physiology. B, Comparative biochemistry》1990,95(2):219-223
1. The enzyme bilirubin uridine diphosphate glucuronyltransferase (UDPGT) was purified and characterized from the liver of eel, Anguilla japonica. 2. The molecular weight of the enzyme was 88,000. 3. The optimal working pH of the enzyme was 7.5-8.0. The optimal working temperature of the enzyme was around 46 degrees C. 4. The Km of bilirubin and uridine diphosphate glucuronic acid for this enzyme was 1.6 mM and 1.8 mM respectively. 5. The concentration of bilirubin did not show any significant effect of inhibition on this enzyme up to 3.3 mM. 6. Since this is the first time UDPGT has been purified and characterized from poikilothermic aquatic animals, it provided interesting information on evolution and adaptation of this enzyme when compared to that of mammals. 相似文献
22.
Suction volume and filtering efficiency of silver carp (Hypophthalmichthys molitrix Val.) and bighead carp (Aristichthys nobilis Rich.) 总被引:1,自引:0,他引:1
Shuanglin Dong Deshang Li Xuwen Bing Qingfeng Shi Fang Wang 《Journal of fish biology》1992,41(5):833-840
Experiments were conducted to measure the suction volume of silver carp and bighead carp of age 1 + with respiratory chamber, and to calculate the suction volume and the filtering efficiency with respect to changes in concentrations of food particles. Suction volume (B. ml/mouth) and filtering efficiency (E. %) were calculated using the following formula: C 1=C0(1-BE/v)n where C0 and C1 were the concentrations of specific food particles at the beginning and at the end of experiment, respectively, V was the volume (ml) of experimental water, and n was the total number of observation of suction made during the experimental period. The relationships between suction volume (ml/mouth) of age I+ silver carp (Bh) and bighead carp (Ba) and their standard lengths (L, cm) were: B h=0.561L-8.94, Ba= 0.627L-7.48 while those of the fingerlings were: B h= O.l70L-0.837, Ba= 0.157L-0.418. The suction volume of the fingerlings was mainly affected by fish size, the function of temperature between 15 and 25° C being negligible. However, temperature affected filtering rate (filtered volume per unit time) through its effect on filtering frequency. The filtering efficiency of the fishes for rotifers (Brachionus caliciflorus) was 100 per cent. The relationships between filtering efficiency and sizes of food particles smaller than or equal to that of a rotifer were: E h=25.1 ln e.s.d. -13.6, Ea=22.2 In e.s.d. -33.1 where Eh and Ea were filtering efficiency of silver carp and bighead carp, respectively, and e.s.d. was the equivalent spherical diameter (μm) of food particles. 相似文献
23.
S-adenosylmethionine stimulates fatty acid metabolism-linked gene expression in porcine muscle satellite cells 总被引:2,自引:0,他引:2
Evidence indicates that both S-adenosylmethionine (SAMe) metabolism and intramuscular fat are associated with insulin resistance
and type II diabetes. However, it is still unknown whether SAMe have effects on intramuscular adipogenesis. The present study
investigated the roles of SAMe in the adipogenic differentiation of porcine muscle satellite cells. Cells isolated from neonatal
pig muscle were treated with different concentrations of SAMe (0, 0.5 and 1.0 mM) for 24 h, induced for a 9-day adipogenic
differentiation and were finally stained by oil red O staining. The adipocyte determination and differentiation factor-1 (ADD1)
and peroxisome proliferator-activated receptor gamma (PPARγ) mRNA and protein were stimulated by SAMe treatment in a dose-dependent
manner. Lipoprotein lipase (LPL) mRNA and protein were enhanced in 1.0 mM treatment group, compared with the control. No significant
difference was observed in the intracellular lipid content among treatments. These results provide evidence that SAMe may
be associated with intramuscular adipogenesis and indicate a novel action of SAMe in fat metabolism. 相似文献
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Nancy J Hintz Don G Ennis Wen Fang Liu Steven H Larsen 《FEMS microbiology letters》1995,127(3):175-179
Abstract The recA gene of Chlamydia trachomatis was isolated by complementation of an Escherichia coli recA mutant. The cloned gene restored resistance to methyl methanesulfonate in E. coli recA mutants. The DNA sequence of the chlamydial gene was determined and the deduced protein sequence compared with other RecA proteins. In E. coli recA deletion mutants, the cloned gene conferred moderate recombinational activity as assayed by Hfr matings. The chlamydial recA gene was efficient in repairing alkylated DNA but less so in repairing of UV damage when compared with the E. coli homologue. As detected by an SOS gene fusion, a small but measurable amount of LexA co-cleavage was indicated. 相似文献