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31.
32.
Comparison of two serologically distinct ribonucleic acid bacteriophages. II. Properties of the nucleic acids and coat proteins 总被引:13,自引:0,他引:13
Overby, L. R. (University of Illinois, Urbana), G. H. Barlow, R. H. Doi, Monique Jacob, and S. Spiegelman. Comparison of two serologically distinct ribonucleic acid bacteriophages. II. Properties of the nucleic acids and coat proteins. J. Bacteriol. 92:739-745. 1966.-The ribonucleic acid (RNA) molecules and coat proteins of two RNA coliphages, MS-2 and Qbeta, have been characterized. MS-2 RNA shows an S(20,w) of 25.8 and a molecular weight by light scattering of 10(6). The corresponding parameters for Qbeta-RNA were 28.9 and 0.9 x 10(6). A difference in base composition was reflected in the adenine-uracil ratio, which was 0.95 for MS-2 and 0.75 for Qbeta. The two RNA preparations are readily separated by chromatography on columns of methylated albumin. Both gave identical bouyant densities in cesium sulfate of 1.64 g/ml. The coat protein subunits were of similar molecular weights: 15,500 (Qbeta) and 14,000 (MS-2). They differed, however, in that the Qbeta-protein lacked tryptophan and histidine, whereas the MS-2 protein lacked only histidine. 相似文献
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N Tomita A Horii S Doi H Yokouchi K Shiosaki M Higashiyama N Matsuura M Ogawa T Mori K Matsubara 《Gene》1989,76(1):11-18
A novel type of alpha-amylase was detected in a lung carcinoid tissue after surveying the cDNA library constructed from this tumor mRNA. Nucleotide sequence analysis showed that the amylase expressed in this carcinoid tumor has 13 and 6 amino acid substitutions when compared with salivary amylase (Amy1) and pancreatic amylase (Amy2), respectively. The nucleotide sequence homologies of cDNAs between this carcinoid amylase and amy1, amy2 are 97.5% and 98.2%, respectively. The nucleotide sequence comparison strongly suggests that this new amylase is the product of the amy3 gene that has been detected in human genome [Emi et al., Gene 62 (1988) 229-235] 相似文献
35.
S Sumi K Inoue R Hosotani M Kogire R Doi M Yun S Higashide H Minote K Takaori H Kaji 《Life sciences》1990,47(13):1115-1119
The effect of intravenous administration of human epidermal growth factor on the splanchnic blood flows was examined in anesthetized dogs, using an ultrasonic transit-time volume flow meter. Human epidermal growth factor (0.1, 0.5 and 1 microgram/kg) significantly increased blood flows in the portal vein (36.9 +/- 7.4% at 1 microgram/kg) and the superior mesenteric artery (49.0 +/- 16.8% at 1 microgram/kg). Systemic blood pressure monitored simultaneously was significantly decreased (8.4 +/- 1.2% at 1 microgram/kg). This study is the first to demonstrate that intravenous administration of epidermal growth factor increases the portal venous blood flow. 相似文献
36.
Nakazawa Miki; Kakihana Junko; Hisabori Toru; Manabe Katsushi 《Plant & cell physiology》1990,31(6):789-796
Procedures for the purification of native phytochrome from etiolatedpea seedlings without the use of immuno-purification techniquesare described. Phytochrome (in the PFR form) was purified bypolyethyleneglycol fractionation, adsorption to pentyl agaroseand batch elution, chromatography on DEAE-Sepharose, adsorptionto phenyl Toyopearl and batch elution, and chromatography onRed Toyopearl. The resulting phytochrome had specific absorbanceratios (SAR = A666/A280 of PR) that ranged from 0.55 to 0.6.The subsequent chromatography on Sephacryl S-300 yielded verypure phytochrome with a SAR of 0.98. PR and PFR peaks in thedifference spectrum of the phytochrome were centered at 665and 730 nm, respectively. The spectral change ratio (Ar/Afr)of the difference spectrum was unchanged after the chromatographyon phenyl Toyopearl, and the value was 1.051.08, indicatingthat the spectral properties of this preparation were intact.The absorption spectra indicated that the peak absorbance ofPFR was at 728730 nm and that of PR was at 666667nm. These peak positions were essentially same as those obtainedwith the undegraded oat phytochrome. Incubation of the samplepurified on Sephacryl S-300 at 25?C for 5 h in either the PRor PFR form did not result in degradation of the molecule. Therate of dark reversion of PFR observed with the purified peaphytochrome was similar to that observed in vivo. The additionof dithionite had no effect on the reversion rate.
2Present address: Fuji-Gotenba, Research Lab. of Chugai PharmaceuticalCo. Ltd., Gotenba, Shizuoka, 412 Japan (Received February 22, 1990; Accepted May 28, 1990) 相似文献
37.
K Nomoto T Takemoto M Maeda Y In M Doi M Inoue T Ishida 《Biochemical and biophysical research communications》1992,187(1):325-331
As an aid for developing a new type of potent insecticide acting on the neuromuscular junction, conformational characteristics of domoic acid and isodomoic acid A, the naturally occurring glutamate agonists, were investigated by X-ray crystal analyses. Conformational comparison with a neuroactive alpha-kainic acid provides information concerning the stereochemical feature responsible for the biological activity. 相似文献
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M. Kato H. J. Bao C.-K. Kang T. Fukui Y. Doi 《Applied microbiology and biotechnology》1996,45(3):363-370
Pseudomonas sp. 61-3 (isolated from soil) produced a polyester consisting of 3-hydroxybutyric acid (3HB) and of medium-chain-length 3-hydroxyalkanoic
acids (3HA) of C6, C8, C10 and C12, when sugars of glucose, fructose and mannose were fed as the sole carbon source. The polyester produced was a blend of homopolymer
and copolymer, which could be fractionated with boiling acetone. The acetone-insoluble fraction of the polyester was a homopolymer
of 3-hydroxybutyrate units [poly (3HB)], while the acetone-soluble fraction was a copolymer [poly(3HB-co-3HA)] containing both short- and medium-chain-length 3-hydroxyalkanoate units ranging from C4 to C12:44 mol% 3-hydroxybutyrate, 5 mol% 3-hydroxyhexanoate, 21 mol% 3-hydroxyoctanoate, 25 mol% 3-hydroxydecanoate, 2 mol% 3-hydroxydodecanoate
and 3 mol% 3-hydroxy-5-cis-dodecenoate. The copolyester was shown to be a random copolymer of 3-hydroxybutyrate and medium-chain-length 3-hydroxyalkanoate
units by analysis of the 13C-NMR spectrum. The poly(3HB) homopolymer and poly (3HB-co-3HA) copolymer were produced simultaneously within cells from glucose in the absence of any nitrogen source, which suggests
that Pseudomonas sp. 61-3 has two types of polyhydroxy-alkanoate syntheses with different substrate specificities.
Received: 9 June 1995/Received last revision: 30 October 1995/Accepted: 6 November 1995 相似文献
40.