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991.
992.
An exocellular protease having the activity of coagulase was synthesized by Bacillus subtilis var. amyloliquefaciens when the growth medium contained no nitrogen sources. The removal of a nitrogen source from the medium was found to induce the synthesis of exoproteases by washed bacterial cells. Protein as a sole source of nitrogen in the medium inhibited rather than induced the biosynthesis of proteases possessing the activity of coagulase by the cells. The production of exoproteases with the coagulase activity was inhibited when a mixture of amino acids was used as a sole nitrogen source. 相似文献
993.
994.
O S Gladysheva D M Kukushkina V A Opritov I M Shvets 《Zhurnal evoliutsionno? biokhimii i fiziologii》1985,21(2):201-203
Bioluminescent analysis has been made of the effect of oxygen supply on the content of ATP in the isolated olfactory epithelium of the frog. It was shown that storage of epithelium preparations in the air increases their ATP content. When preparations are kept in the atmosphere of an inert gas, ATP level in the epithelium rapidly decreases, being recovered after transition of preparations to the air medium. The data obtained indicate the existence of apical type of respiration in the olfactory epithelium of the frog. 相似文献
995.
996.
997.
998.
999.
1000.
1. The influx and efflux of labelled substances with and without chloroquine was studied in yeast cells. 2. The uptake of delta-aminolevulinic acid by Saccharomyces cerevisiae is characterized by a KT of 3-4 mM and Jmax of 1.0-1.2 mumol min-1 g dry weight-1. 3. A method for loading yeast with labelled coproporphyrin is suggested. 4. The uptake of sorbitol and coproporphyrin was slightly stimulated, while the uptake of 6-deoxyglucose was slightly, that of 2-aminoisobutyric acid and leucine strongly inhibited by chloroquine. 5. The efflux of coproporphyrin, 2-aminoisobutyric acid and sorbitol was stimulated while that of leucine was not influenced by chloroquine. 6. The result showed that chloroquine influenced directly but nonspecifically the membrane permeability, apparently mainly that of the vacuolar membrane. 相似文献