Chroma tophore

The protein in citrus is generally associated with the solid portions of the fruit, i.e., the seeds, flavedo, albedo, chroma-tophores, and pulp. Some of these components find their way into the juice along with the available free amino acids during extraction and processing and storage. Studies conducted in our laboratories (42,43,44) and by others (45) have shown that reductions in the pulp content of juice slow the rate of browning. 

There are two exceptions from this generalization, one of which is the transhydrogenase factor isolated from Rhodospirillum rubrum chroma-tophores 109-112). This factor is obligatory for both energy-linked and non-energy-linked transhydrogenation its properties and function have already been reviewed (see Section III,D). Butlin 167 see also 73) re-... 

Pigments.— These are substances which give color to various plant parts in which they are found. They occur either in special protoplasmic structures, as chloroplasts, chromoplasts or chroma-tophores, or dissolved in tjie cell sap. Of the pigments named the following will be considered Chlorophyll, Xanthophyll, Chromophyll, Etiolin, Anthocyanin, Phycocyanin, Phycophxin, and Phycoerythrin. 

Recently, it was shown that Ca induces intrinsic uncoupling of the FF.-ATPase from chloropl ots (1). In this communication we examine the effect of Ca upon the activities of the FF -ATPase of Rhodospirillum rubrum chroma-tophores and also the possibility of intrinsic uncoupling by other divalent cations. The effect of these ions on the ATPase activity of purified F -ATPase is also examined. 

Table 2. Effects of Dio-9 and equisetin on the membrane bound chroma-tophore, chloroplast and mitochondrial PPase activities. 30 yg/ml Dio-9 was used for chromatophore PPase, 25 pg/ml Dio-9 for chloroplast PPase and 60 pg/ml Dio-9 for mitochondrial PPase. Concentration of equisetin was 80 pM.

Determination of the steady-state level of PPI In chroma-tophores The assay was perfomred at room temperature. In a reaction mixture containing 0.2 M glycylglycine, pH 7.4, 0.1 mM succinate, 1-10 mM MgCl2 and chromatophores corresponding to 23 pM BChl. The mixture was illuminated for 20 min. The reaction was terminated by addition of 0.2 ml 20% TCA. 10 yl from a 10 times diluted reaction mixture was taken for PPI determination as described above. 

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See also in sourсe #XX -- [ , , ]

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