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  1. (1) Changes in the composition pattern of acid soluble basicproteins in Chlorella cells during their life cycle were studiedusing various methods of fractionation ; i. e., extraction,chromatography on CM-Sephadex column and electrophoresis onpolyacrylamide gel, etc.
  2. (2) The content of basic proteinswas of the order of 1-2.5%of the dry weight of cells and showeda maximum at the Dn stageand a minimum at the formative stages(L2, L3). The change wasdue to basic proteins (I-HC1) whichwere insoluble in 0.14 MNaCl and were non-elutable with 2 MNaCl from CM-Sephadex. The0.14 M NaCl soluble basic proteincontent remained almost constantthroughout the life cycle.
  3. (3) The I-HC1 fraction in question showed 20 bands and shouldersin electrophoresis on polyacrylamide gels. Some components showedremarkable changes in their relative quantities during the lifecycle, while others exhibited relatively little change.
  4. (4)Preliminary fractionation experiments of subcellular componentsby a non-aqueous method showed that the basic proteins showingmarked changes in their relative amounts were present in a nucleus-richfraction, and those exhibiting little change were found in achloroplast-rich fraction, except one main component which showedcharacteristic behavior.
(Received June 22, 1968; )  相似文献   
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1. In an experimental flume, we examined the effects of a biomass reduction and alteration of taxonomic composition, because of grazing by the fish Plecoglossus altivelis, on the net biomass accumulation of periphyton. 2. Grazed and ungrazed assemblages with different biomass and taxonomic composition were first prepared in fish enclosures and exclosures, respectively. These assemblages were then set out in the flume and incubated for 2 days under grazing‐free conditions to examine (i) the relationship between biomass and biomass accumulation rate and (ii) the effect of taxonomic composition on the relationship between these two. 3. The grazed and ungrazed assemblages were dominated by upright filamentous cyanobacteria and diatoms, respectively. The rate of biomass accumulation decreased with increasing periphyton biomass in both the grazed and ungrazed assemblages, and was lower in the grazed than the ungrazed assemblages at any biomass level. 4. The results showed that the reduction in biomass and the alteration of taxonomic composition due to fish grazing have opposite effects on biomass‐specific productivity. Biomass accumulation rate increased in response to biomass reduction, although a shift in dominance from diatoms to upright filamentous cyanobacteria decreased the overall productivity of the periphyton.  相似文献   
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The cells of Chlorella ellipsoidea were grown synchronously,and at different stages of their life cycle, the cells wereanalysed for their contents in amino acids existing in freeforms as well as in the fractions of bulk protein and peptides.Throughout the algal life cycle, the content of bulk protein(per unit dry weight of cells) remained relatively constant,being about 20 to 40 times those of peptides and free aminoacids. The amino acid composition of the protein fraction alsoremained fairly constant, the predominant amino acids beingalanine, glutamic acid, glycine and leucine. The contents inthe bulk peptides increased appreciably during the periods ofgrowth and "ripening" (light period), and decreased markedlyduring the periods of "post-ripening" and cellular division(dark period). Similar modes of change in content were alsoobserved in most of the individual amino acids contained inthe peptide fraction. The most abundant component in the peptidefraction was arginine followed by glutamic acid, glycine andcyst(e)ine. Rather irregular was the mode of change of the levelsof individual free amino acids, although, as a whole, theirbehavior was similar to that of bulk peptides, increasing duringthe light period and decreasing during the dark period. Themost predominant free amino acids were glutamic acid and alaninefollowed by proline. Experimental evidence showed that the processes of formationof free amino acids and peptides are for the most part lightdependent, while the synthesis of protein, which is thoughtto be effected using as building blocks mostly free amino acids—formeddirectly or indirectly from early photosynthates or derivedfrom pre-formed peptides—is essentially a light-independentprocess. Peptides, as a whole, seem to have significance asreservoirs of building blocks for the syntheses in the darkof protein and other nitrogenous cellular substances. The synthesisof protein in the dark takes place not only by consuming thefree amino acids and peptides that have been accumulated duringthe light period, but also by assimilating the exogenous nitrogensource (nitrate). The distribution of individual amino acidsin the three main fractions mentioned above as it changed duringthe course of algal cell cycle was followed in detail, and theresults obtained were discussed in relation to various relevantdata reported by other workers. (Received June 29, 1964; )  相似文献   
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NEW ARGININE-CONTAINING PEPTIDES ISOLATED FROM CHLORELLA CELLS   总被引:1,自引:0,他引:1  
Seven kinds of arginine-containing peptides were isolated fromthe cells of Chlorella ellipsoidea, and their structures wereinvestigated. Their amino acid make-ups and quantities presentin randomly grown algal cells were found to be as follows (indecreasing order of contentin moles per dry weight of cells): Arg-Arg, Arg-Arg-Glu, Arg-Arg-Arg, Arg-Glu> Arg-(Arg2, Glu)-Glu>Arg-(Arg3,Glu), Arg-(Glu, Asp) Using synchronously mass-cultured algal cells, the quantitiesof these peptides as they changed during the algal life cyclewere followed. It was found that, except in the case of Arg-Arg-Arg,the contents (in moles per dry weight of cells) of the peptides(i) markedly increased during the stages from Dn to L1, (ii)remained almost constant or more or less appreciably increasedduring the stages from L1 to L3, and (iii) decreased sharplyduring the transformation of L3-cells (via L4) into Dn-cellsin the dark. The content of Arg-Arg-Arg remained almost constantduring the period from Dn to L3, and on transference of L3-cellsin the dark it increased temporarily and then decreased duringthe transformation of L4-cells into Dn-cells. Significance andpossible roles of these peculiar peptides in the life cycleof Chlorella were discussed. (Received May 10, 1965; )  相似文献   
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By growing Chlorella ellipsoidea synchronously by the techniqueof TAMIYA et al. with some modifications, it was demonstratedthat cellular division of ripened cells (L2- and L3-cells) inthe dark is specifically inhibited—especially stronglyat pH 6.3—by cupric ion present in the medium. The possibleattack site of cupric ion in cellular division of this algais discussed. (Received March 12, 1969; )  相似文献   
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