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941.
O. V. Yagodina E. B. Nikol’skaya I. Y. Shemarova A. E. Khovanskikh 《Journal of Evolutionary Biochemistry and Physiology》2000,36(3):244-248
A comparison has been performed of catalytic properties of unicellular microorganism amine oxidases (AO) from two new enzyme
sources, the bacteriumMethanosarcina barkeri and the infusoriaTetrahymena pyriformis. It was shown that the both studied AO deaminate tyramine, serotonin, and benzylamine, but do not deaminate histamine. The
AO fromMethanosarcina barkeri catalyzes deamination of all three substrates at an identical rate, while the rate of tyramine deamination under effect of
AO fromTetrahymena pyriformis is one order higher than the rate of serotonin deamination, and about two orders higher than the rate of benzylamine deamination.
Based on the data of the substrate-inhibitor analysis, a suggestion was made about the existence of one center for the substrate
binding in the AO of the studied bacterium, while several centers in the AO of the studied infusoria. 相似文献
942.
J De Coninck I Verdier-Denantes F Duyme S Bouquelet V Dumortier 《Journal of industrial microbiology & biotechnology》2000,25(1):58-61
Oxygen concentrations stimulated growth (maximum number of cells) and protease secretion by Tetrahymena thermophila. Agitation and aeration conditions for growth and protease secretion were optimised by a central composite design. The best
optimised combination was a stirrer speed of 338 rpm and an aeration of 1 vvm. Journal of Industrial Microbiology & Biotechnology (2000) 25, 58–61.
Received 24 September 1999/ Accepted in revised form 06 March 2000 相似文献
943.
A rapid, sensitive, assay for enzymes that degrade heparin is described. The procedure is based on the interference of heparin with color development during the interaction of protein with the dye Coomassie brilliant blue. The loss of this property when the glycosaminoglycan is degraded by heparinase can be used to quantify activity of the enzyme in pure form, or in complex biological samples such as tissue homogenates or serum. The assay is also suitable for studying dependence of heparinase activity under conditions such as varying pH and temperature. 相似文献
944.
Conventional amperometric alcohol electrodes were constructed with oxygen- and hydrogen peroxide-base sensors and a much improved electrode was designed by placing a hydrophobic, gas-permeable membrane over the conventional hydrogen peroxide-based alcohol electrode. The immobilization of alcohol oxidase with glutaraldehyde was also studied and optimized. The upper linear ranges of the conventional and newly designed alcohol electrodes were 0.02 and 0.5% ethanol, respectively. The hydrophobic membrane of the new design eliminated the classical electrochemical interferences of hydrogen peroxide-based electrodes and the typical pH dependence of enzymatic systems. 相似文献
945.
Procedure and Analysis of a Useful Method in Determining Mycelial Dry Weights from Agar Plates 下载免费PDF全文
The evaluation of growth by dry weight determination of fungus mycelium for agar plates was examined. The data obtained were statistically analyzed. This method was shown to be sufficiently accurate to be used as an investigative tool. 相似文献
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Brunner RM Srikanchai T Murani E Wimmers K Ponsuksili S 《Molecular biology reports》2012,39(1):97-107
Six genes that were known to exhibit expression levels that are correlated to drip loss BVES, SLC3A2, ZDHHC5, CS, COQ9, and
EGFR have been for candidate gene analysis. Based on in silico analysis SNPs were detected, confirmed by sequencing, and used for genotyping. The SNPs were genotyped in about 1,800 animals
from six pig populations including commercial herds of Pietrain (PI) and German Landrace (DL), different commercial herds
of Pietrain × (German Large White × German Landrace) (PIF1(a/b/c)), and one experimental F2-population Duroc × Pietrain (DUPI). Comparative and genetic mapping established the location of BVES on SSC1, of SLC3A2 and
ZDHHC5 on SSC2, of CS on SSC5, of COQ9 on SSC6 and of EGFR on SSC9, respectively, coinciding with QTL regions for carcass
and meat quality traits. BVES, SLC3A2, and CS revealed association at least with drip loss and with several other measures
of water holding capacity (WHC). Moreover, COQ9 and EGFR were associated with several meat quality traits such as meat color
and/or thawing loss. This study reveals statistic evidence in addition to the functional relationship of these genes to WHC
previously evidenced by expression analysis. This study reveals positional and genetic statistical evidence for a link of
genetic variation at these loci or close to them and promotes those six candidate genes as functional and/or positional candidate
genes for meat quality traits. 相似文献