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161.
Flagella were prepared and purified in a relatively intact form from bacterial lysates. Immunochemical tests showed that over 95% of the protein in the final preparation consisted of flagellar antigen. These flagella are more stable to thermal denaturation than flagella filaments obtained by shearing. Their thermal properties more closely resemble those of flagella in the native state on bacteria. The presence of the hook structure is responsible for this extra stability. 相似文献
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164.
Oximes, nitriles and 2-hydroxynitriles as precursors in the biosynthesis of cyanogenic glucosides
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The biosynthesis of the cyanogenic glucosides, linamarin and prunasin, was investigated in linen-flax, peach and cherry-laurel shoots. It was shown that related 2-oximino acids, aldoximes, nitriles and 2-hydroxynitriles were generally good precursors of the aglycone moiety. Studies with double-labelled compounds confirmed the retention of the oximino nitrogen atom from 2-oximinoisovaleric acid and isobutyraldoxime in the biosynthesis of linamarin. A general pathway from amino acids to cyanogenic glucosides involving N-hydroxyamino acids, aldoximes, nitriles and 2-hydroxynitriles is proposed. 相似文献
165.
Positioning Flagellar Genes in Escherichia coli by Deletion Analysis 总被引:12,自引:10,他引:2
166.
H N Antoniades J D Simon D Stathakos 《Biochemical and biophysical research communications》1973,53(1):182-187
[125I]-insulin, injected in rats, was converted into high molecular weight forms as judged by gel filtration of blood serum samples collected at various intervals. These forms represented 26% (10 min. after injection) to 81% (240 min. after injection) of the total immunoprecipitable radioactivity. Their molecular weights were not affected by rechromatography in 0.1 M borate buffer (pH 8) or in 8 M urea-1 M acetic acid (pH 2.4). On incubation of [125I]-insulin with blood serum , no high molecular weight forms could be observed. 相似文献
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169.
Trisomy 18 associated with a familial translocation t(Bq-; 18q+) 总被引:2,自引:0,他引:2
170.
Phytochrome Control of Maize Leaf Inorganic Pyrophosphatase and Adenylate Kinase 总被引:1,自引:1,他引:0
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Brief exposure of etiolated maize seedlings to light induces large increases in adenylate kinase and inorganic pyrophosphatase activity of the leaf in the following 48 hr in the dark. Red light is more effective than white or far red light, and far red reverses the effect of red light, indicating phytochrome control. Out of several tested, only these 2 enzymes appear to be coordinately induced, which is consistant with their close functional relationship. For inorganic pyrophosphatase, light treatment induces biosynthesis of a distinctive form of the enzyme characteristic of chloroplasts, readily separable from the enzyme characteristic of etiolated tissue. 相似文献