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41.
We have reported the existence of a phosphonoglycosphingolipid containing a pyruvylated galactose, FGL-IIb, in nerve fibers of Aplysia kurodai (Araki, S., Abe, S., Ando, S., Kon, K., Fujiwara, N. & Satake, M. (1989) J. Biol. Chem. 264, 19922-19927). We have now isolated two other pyruvylated galactose-containing phosphonoglycosphingolipids, named FGL-V and FGL-IIa, from the nervous tissue of Aplysia, and characterized them as [3,4-O-(S-1-carboxyethylidene)]Gal beta 1----3GalNAc alpha 1----3[6'-O-(2- aminoethylphosphonyl)Gal alpha 1----2] (2-aminoethylphosphonyl----6) Gal beta 1----4Glc beta 1----1 ceramide and [3,4,O-(S-1-carboxyethylidene)] Gal beta 1----3GalNAc alpha 1----3[6'-O-(2-aminoethylphosphonyl)Gal alpha 1----2]Gal beta 1----4Glc beta 11----ceramide, respectively. Their major aliphatic components are palmitic acid, octadeca-4-sphingenine and anteisononadeca-4-sphingenine. Thus, the nervous system of Aplysia contains several pyruvylated phosphonoglycolipids. 相似文献
42.
Use of whey for production of exocellular polysaccharide by a mutant strain ofXanthomonas campestris
Growth and kinetics of the production of exocellular polysaccharide was studied in a mutant strain ofXanthomonas campestris lac
+ during cultivation in a submerged culture in a medium containing whey. The maximum production of the polymer was observed
at the initial stage of the stationary growth phase of the culture. The mean production yield was about 1.4%. The results
were comparable with those obtained during cultivation on a lactose medium.
Translated by Č. Novotny 相似文献
43.
44.
Dagmar Jičínská Eduard Brabec Marcel Rejmánek Jan Jeník Joří Haager Josef Holub Věroslav Samek Hana Rambousková Josef Holub Marie Naděžda Končalová Robert Neuhäusl Josev Kyncl František Krahuleo Jaroslav Dobrý Blanka Úlehlová Jiří Úlehla Eliška Rybníčková Kamil Rybníček 《Folia Geobotanica》1982,17(4):431-448
45.
Respiratory metabolism of Giardia lamblia 总被引:5,自引:0,他引:5
E C Weinbach C E Claggett D B Keister L S Diamond H Kon 《The Journal of parasitology》1980,66(2):347-350
46.
47.
Hirokazu Yamamoto Kunimoto Hotta Yoshiro Okami Hamao Umezawa 《Biochemical and biophysical research communications》1981,100(3):1396-1401
SS-939 was resistant to its own aminoglycoside antibiotics, istamycins, as well as kanamycin A, neamine, ribostamycin and butirosin A, but was susceptible to neomycin B, lividomycin A and streptomycin. This resistance to these antibiotics was found to be due to ribosomes of the strain. 相似文献
48.
Results obtained when studying conjugation in mycobacteria by means of different methods are summarized. The method of conjugation on surface of a solid complete medium was tested with different auxotrophic mutants of different strains ofMycobacterium smegmatis. It was not possible to obtain positive results even by means of the above method. This was probably due to unsuitability of the chosen strains ofMycobacterium smegmatis. Preparation of the donor strain by transfer of the F factor fromEscherichia coli F’ORF 1ade + lac+ pro+ toMycobacterium phlei PA adeStm r by means of sexduction is described. Frequency of the phenotype PAade + Stmr increased in the average by two and a half orders of magnitude with respect to the control, however, a further transfer from cultures of the cellsade + Stmr to cells ade could not be demonstrated. Experiments aimed at transferring the R factor from strainsEscherichia coli K-12 toMycobacterium phlei were unsuccessful. 相似文献
49.
50.
Current forest growth models and yield tables are almost exclusively based on data from mature trees, reducing their applicability to young and developing stands. To address this gap, young European beech, sessile oak, Scots pine and Norway spruce trees approximately 0–10 yr old were destructively sampled in a range of naturally regenerated forest stands in Central Europe. Diameter at base and height was first measured in situ for up to 175 individuals per species. Subsequently, the trees were excavated and dry biomass of foliage, branches, stems and roots was measured. Allometric relations were then used to calculate biomass allocation coefficients (BAC) and growth efficiency (GE) patterns in young trees. We found large differences in BAC and GE between broadleaves and conifers, and also between species within these categories. Both BAC and GE are strongly age-specific in young trees, their rapidly changing values reflecting different growth strategies in the earliest stages of growth. We show that linear relationships describing biomass allocation in older trees are not applicable in young trees. To accurately predict forest biomass and carbon stocks, forest growth models need to include species and age-specific parameters of biomass allocation patterns. 相似文献