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1.
J D Zajac S A Livesey T J Martin 《Biochemical and biophysical research communications》1984,122(3):1040-1046
When the F1-ATPase from the thermophilic bacterium, PS3, was inactivated by 90% with 7-chloro-4-nitro[14C]benzofurazan ([14C]Nbf-Cl) at pH 7.3 and then gel-filtered, 1.25 mols of [14C]Nbf-O-Tyr and less than 0.1 mol of Nbf-N-Lys were formed per mol of enzyme. After adjusting the pH of the gel-filtered, modified enzyme to 9.0 and incubating it for 14 hrs. at 23 degrees C to promote O----N migration, 0.68 mol of Nbf-N-Lys were formed per mol of enzyme while about 16% of the original activity reappeared. Isolation of the subunits after the O----N migration showed that 90% of the incorporated 14C was present in the beta subunit, which contained 0.21 mols of [14C]Nbf-N-Lys per mol. A tryptic peptide which contained the majority of the 14C incorporated into the beta subunit was isolated and subjected to automatic amino acid sequence analysis contained 38 residues. The amino acid sequence immediately around the lysine residue labeled with [14C]Nbf-, K*, was found to be: ...I-G-L-F-G-G-A-G-V-G-K*-T-V-L-I-G... . 相似文献
2.
Summary Familial occurrence of 1/21 translocation in connection with trisomy 21 was described. The possibilities of inheritance of further chromosome rearrangements arising during the gametogenesis of persons with this translocation were considered. 相似文献
3.
Winter rape ( Brassica napus L., var. olifera cv. Górczanski) seedlings were exposed to hardening conditions and the content and composition of free sterols as well as the ratio of free sterols to total phospholipids were determined. There was a reduction in free sterol content in the leaves at the most advanced stage of hardening. The ratio of free sterol to total phospholipids was significantly reduced by hardening due to a decrease in the level of the former and an increase in that of the latter compounds. There was a negative correlation between this ratio and the temperature at which half of the seedlings died. Thus, adaptation of membranes to temperature takes place also at the level of sterol-phospholipid interactions. Exposing seedlings already hardened to freezing temperatures caused injury higher than 50%, and brought about a drastic increase in the level of free sterols and an elevation in the ratio of free sterols to phospholipids. The results are discussed in terms of a possible role of the molecular architecture of membranes in surviving at subzero temperatures. 相似文献
4.
Almost 100% of 7- to 10-day-old Hymenolepis diminuta became established when surgically transplanted from donor mice into the duodenum of naive recipient mice. Transplanted tapeworms survived 8-12 days, by which time they had survived much longer in total than they would have done in the donor. Mice previously immunized by a primary infection rejected transplants within 4 days. Sub-lethal irradiation (550 rad) delayed rejection by immune mice but such mice still rejected worms much more quickly than did naive mice. Surgery was shown to delay by 2-3 days the rejection of worms by naive mice, and the importance of circumventing surgery by administering the worms per os is emphasized. Prospects for reconstituting irradiated immune mice are considered vis-à-vis work with nematodes, and the differences which, on present knowledge, appear to exist between nematode and cestode rejection are briefly discussed. 相似文献
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The concept of a dangeardien is discussed in relation to the ascomycetous yeasts. In species of ascomycetous affinity the dangeardien may be expressed not only as the ascus, but also in the taxa showing an alternation of generation in the absence of an ascosporal state, as a site of reduction division. In such cases it is proposed to refer to the dangeardien as a meioconidiophore and to the externally delimited haplophase, as meioconidia. Taxa showing the formation of meioconidiophores are considered to represent perfect states. 相似文献
7.
It has been found that the type strain of Torulopsis dattila constitutes a perfect state since it is characterized by the formation of asci which rupture at maturity liberating 1–4 smooth, spheroidal ascospores which tend to agglutinate. On the basis of its physiological properties this strain is considered to be representative of Kluyveromyces thermotolerans. 相似文献
8.
Krzysztof W. Pankiewicz Marek M. Kabat Elzbieta Sochacka Lech Ciszewski Joanna Zeidler Kyoichi A. Watanabe 《Nucleosides, nucleotides & nucleic acids》2013,32(5-6):589-593
Abstract 5-(β-D-Ribofuranosyl)nicotinamide (lie) and 6-(β-D-ribo-furanosyDpicolinamide (IId) and their corresponding o-isomers (III) were synthesized from ribonolactone. The C-nucleoside lie was further converted to its 5′-monophosphate Up which is isosteric to NMN Ip). 相似文献
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