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Shedding of vesicular stomatitis virus soluble glycoprotein by removal of carboxy-terminal peptide. 总被引:9,自引:5,他引:4
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A comparison of partial NH2-terminal sequences of vesicular stomatitis viral glycoprotein G (molecular weight, 69,000) and the soluble extracellular glycoprotein antigen Gs (molecular weight, 57,000) shows that both of the sequences are identical. Tryptic fingerprint analyses show that Gs lacks the carboxy-terminal region containing the membrane-anchoring hydrophobic domain of G. These results suggest that Gs is formed by cleavage in the carboxy-terminal region of G. 相似文献
124.
Summary The influence of continuous cropping and soil test based fertilizer use on the organic nitrogen fractions in the plough layer
has been studied in a Typic Ustochrept soil. Seven years of multiple cropping without manuring caused marked depletion in
all the hydrolysable fractions except unidentified hydrolysable N namely, hexosamine (48.8%), hydrolysable ammonium (23.9%)
and amino acid (7.3%) as compared to an adjacent fallow. Fertilizer nitrogen application maintained the levels of various
forms of N as in the fallow plots and nitrogen in conjunction with phosphorus raised the status of amino acid N. Phosphate
improved the contents of hydrolyzable ammonium and total hydrolyzable N whereas farmyard manure enhanced the latter only.
The system of intensive cropping followed with appreciably high doses of fertilizers favoured greater immobilization of N
in hydrolyzable ammonium and total hydrolyzable fractions.
Original not seen 相似文献
125.
The cotyledon of the seed of Mirabilis jalapa was found to contain a d-glucan. Methylation, periodate oxidation, and graded and enzymic hydrolysis studies were conducted to elucidate its structure. For every 38 d-glucosyl residues therein, 34 are (1→4)- and 3 are (1→3)-linked; the d-glucosyl unit at the branch point is linked through O-1, O-2, and O-4. In some places in the chain, there are at least three (1→3)-linked d-glucosyl residues in a sequence. Both α- and β-d-glucosidic linkages are present in the polysaccharide, the former preponderating. The d-glucan gave with iodine a faint blue color that had λmax 420 nm. 相似文献
126.
127.
Vibrio el tor cells contain a constitutive reductase enzyme which converts nitrofurantoin to an active principle that is responsible for the observed antibacterial activity of the drug. Acquisition of resistance of this strain towards nitrofurantoin is associated with the loss of this reductase. This enzyme is located in the periplasmic region of the nitrofurantoin-sensitive cells, and seems to play an important role in transporting the drug into the cells. 相似文献
128.
129.
Irradiation with X-rays and gamma rays reduced the speed of germination of seeds of jute cultivars,viz., JRO 632, JRO 620, Sudan Green ofCorchorus olitorius and JRC 212, Fanduk, D 154 ofC. capsularis. Though the first phase of germination(i.e. seed variability) remained apparently unaffected, the second phase (i.e. the sprouting ability) and the third phase(i.e. the attainment of autotrophic status) were found to be the best indicators of radiation injury and provided dependable data for the assessment of radiosensitivity. The jute cultivars have not shown accountable intervarietal differences in radiosensitivity in respect of LD 50 and LD 100 for the second and the third phases of germination. 相似文献
130.
Morphological variability of the human chromosomes in two Indian populations - Rajputs and Punjabis.
Karotypic evaluation of 100 Rajputs and 100 Punjabis revealed different frequencies of Y chromosome polymorphism and minor chromosome variants. Long Y chromosome were observed 5% of the Rajputs and 3% of the Punjabis. The Y indices of Rajputs were consistently higher than those of Punjabis. Significant differences were noted between Rajputs and Punjabis with respect to the 5 Y indices. Significant differences were also found when those 2 populations were compared with different populations of the world. Minor chromosome variants were observed in 18% of the Rajputs and 19% of the Punjabis. 相似文献