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1.
Production of berberine could be induced by adding 6-benzylaminopurine (BAP) to Thalictrum minus cells, cultured in suspension in a medium containing 2,4-dichlorophenoxyacetic acid (2,4-D), early in the growth cycle. In the presence of BAP, the precursor, L-tyrosine, was rapidly converted into berberine which was then released into the medium, whereas substantial amounts of the intermediates, tyramine and dopamine, accumulated in non-berberine-producing cells grown in the same 2,4-D-containing medium without BAP. These results suggest that BAP activated enzymatic reactions subsequent to the formation of the amines in the biosynthesis of berberine.Abbreviations 2,4-D 2,4-dichlorophenoxyacetic acid - BAP 6-benzylaminopurine - NAA 1-naphthaleneacetic acid - IAP 6-isopentenylaminopurine - LS medium Linsmaier-Skoog medium - Growth medium LS medium containing 10-6 M 2,4-D  相似文献   
2.
Thirty-eight strains of 12Microsporum and 10Arthroderma (Nannizzia) species were investigated by analysis of mitochondrial DNA with 6 restriction enzymes, and classified into 13 genetic groups. The phylogenetic tree of the 13 groups thus established was constructed. On the tree,M. audouinii, M. langeronii, M. rivalieri, M. distortum, M. equinum, M. ferrugineum andA. otae comprise one genetic group and are suggested to be the same species.A. gypseum, A. fulvum, M. duboisii, M. ripariae, A. incurvatum, A. persicolor andA. obtusum are clustered on one of five boughs of the tree indicating their close relation.A. racemosum andA. cajetani are also closely related.  相似文献   
3.
The relationships among X591, Cyt-b559 and C-550 in the primaryphotoact of PS-II were analysed by examining the effects ofvarious inhibitory substances and treatments on the light-inducedabsorbance changes of these components. The results were fully explainable by the scheme previouslypresented by Huzisige, in which two photoreactions are involvedin PS-II. Our conclusion is that X591 acts as the electron acceptorfor one of the photoreactions in PS-II. (Received October 23, 1978; )  相似文献   
4.
Rhodococcus erythropolis PR4 is a marine bacterium that can degrade various alkanes including pristane, a C(19) branched alkane. This strain produces a large quantity of extracellular polysaccharides, which are assumed to play an important role in the hydrocarbon tolerance of this bacterium. The strain produced two acidic extracellular polysaccharides, FR1 and FR2, and the latter showed emulsifying activity toward clove oil, whereas the former did not. FR2 was composed of D-galactose, D-glucose, D-mannose, D-glucuronic acid, and pyruvic acid at a molar ratio of 1:1:1:1:1, and contained 2.9% (w/w) stearic acid and 4.3% (w/w) palmitic acid attached via ester bonds. Therefore, we designated FR2 as a PR4 fatty acid-containing extracellular polysaccharide or FACEPS. The chemical structure of the PR4 FACEPS polysaccharide chain was determined by 1D (1)H and (13)C NMR spectroscopies as well as by 2D DQF-COSY, TOCSY, HMQC, HMBC, and NOESY experiments. The sugar chain of PR4 FACEPS was shown to consist of tetrasaccharide repeating units having the following structure: [structure: see text].  相似文献   
5.
The Khoisan populations of southern Africa are known to harbor some of the deepest‐rooting lineages of human mtDNA; however, their relationships are as yet poorly understood. Here, we report the results of analyses of complete mtDNA genome sequences from nearly 700 individuals representing 26 populations of southern Africa who speak diverse Khoisan and Bantu languages. Our data reveal a multilayered history of the indigenous populations of southern Africa, who are likely to be the result of admixture of different genetic substrates, such as resident forager populations and pre‐Bantu pastoralists from East Africa. We find high levels of genetic differentiation of the Khoisan populations, which can be explained by the effect of drift together with a partial uxorilocal/multilocal residence pattern. Furthermore, there is evidence of extensive contact, not only between geographically proximate groups, but also across wider areas. The results of this contact, which may have played a role in the diffusion of common cultural and linguistic features, are especially evident in the Khoisan populations of the central Kalahari. Am J Phys Anthropol 153:435–448, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
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7.
Mixed monolayer systems of dipalmitoylglycerophosphocholine (DPPC)-distearoylglycerophosphocholine (DSPC), palmitoylglycerol-DPPC, and palmitoylglycerol-DSPC have been investigated by a previously described thermodynamic treatment. The surface pressures of these systems were measured at various compositions and temperatures. The two-dimensional phase diagrams and the apparent molar entropy and energy changes were evaluated. It was found that the phase diagrams of the DPPC-DSPC, palmitoylglycerol-DSPC and palmitoylglycerol-DPPC systems are all of different types. According to our phase diagram classification, DPPC-DSPC, palmitoylglycerol-DSPC, and palmitoylglycerol-DPPC systems exhibited a modified cigar type, a eutectic type, and a negative azeotropic type, respectively.  相似文献   
8.
Nishide  Eiichi  Anzai  Hirosi  Uchida  Naozuki  Nisizawa  Kazutosi 《Hydrobiologia》1996,326(1):515-518
Kjellmaniella crassifolia, the edible macro-brown alga in Japan contained nearly 27% of alginates of which nearly 7% was extractable from the fronds with boiling water for 6 h and the residual alginates in the frond were almost exhaustively extracted with a dilute alkali at 60 °C for 6 h. The alginates dissolved in all these extracts with both boiling water and dilute alkali were purified by fractionation with MgCl2 and alcohol.The content of MM blocks in the boiling water-soluble alginate sample increased remarkably during heating for 6 h while that of GG blocks from the same sample decreased. In contrast, MM blocks in the alkali-soluble alginate sample decreased during 6 h heating while GG blocks continued to increase. Since the amounts of MG blocks showed slight fluctation, the M:G ratio of alginates extracted with boiling water increased towards the end of extraction whereas the reverse is true for the alkali-soluble alginates.  相似文献   
9.
Mixed monolayer states of long normal-chain fatty acids with distearoylglycerophosphocholine (DSPC) have been studied by a previously described thermodynamic treatment. The surface pressures of mixed monolayers of tetradecanoic, pentadecanoic and octadecanoic acids with DSPC were measured at various compositions and temperatures. The two-dimensional phase diagrams of both the tetradecanoic acid-DSPC and pentadecanoic acid-DSPC systems were determined. They both exhibited eutectic type phase diagrams. In the octadecanoic acid-DSPC system the two components were immiscible both in the liquid-expanded and liquid-condensed states. The apparent molar entropy and energy changes for the tetradecanoic acid-DSPC system were calculated. The values for tetradecanoic acid were negative, as is the usual case. However, the values of DSPC were positive, and their absolute values wer about 14 of that of tetradecanoic acid.  相似文献   
10.
A mucoidal strain of Rhodococcus rhodochrous was resistant to 10% (vol/vol) n-hexadecane, while its rough derivatives were sensitive. When the extracellular polysaccharide (EPS) produced by the mucoidal strain was added to cultures of the rough strains, the rough strains gained resistance to n-hexadecane. Thus, EPS confer tolerance to n-hexadecane in members of the genus Rhodococcus.  相似文献   
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