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1Author    P.-J Enzmann, F. W. EilandRequires cookie*
 Title    Separation of Alphavirus Nucleocapsids from Envelope Fragments  
 Abstract    Methods for the preparation of alphavirus nucleocapsids and envelope fragments for bio­ chemical, electron microscopical and serological investigations are described. Difficulties which have been encountered previously in attempts to isolate viral nucleocapsids for morphological studies, namely disruption o f the fragile particles, have been overcome by treatment with formaldehyde. 
  Reference    Z. Naturforsch. 35c, 145—149 (1980); received July 6 /August 16 1979 
  Published    1980 
  Keywords    Alphaviruses, Nucleocapsid, Envelope, Triton X-100 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-0145.pdf 
 Identifier    ZNC-1980-35c-0145 
 Volume    35 
2Author    Margrit Bertrams, Käthe Wrage, Ernst HeinzRequires cookie*
 Title    Lipid Labelling in Intact Chloroplasts from Exogenous Nucleotide Precursors  
 Abstract    De «ovo-synthesis o f glycerolipids in chloroplasts is initiated by a stroma enzyme which catalyzes the formation o f lyso-phosphatidic acid from glycerophosphate and acyl-CoA. When these substrates are added to isolated, intact chloroplasts, only glycerophosphate can readily pass through the chloroplast envelope which represents a permeation barrier for acyl-CoA, although higher thioester concentrations destroy this membrane system. At low concentrations of acyl-CoA, which do not impair the envelope, intact chloroplasts metabolize exogenous acyl-CoA in two ways to give free fatty acids and labelled phosphatidyl choline. This indicates that the envelope thioesterase can use exogenous substrates. Isolated, intact chloroplasts fixing radioactive C 0 2 label free fatty acids and acylglycerols but not galactolipids, since they cannot convert 3-phosphoglycerate into UDP-galactose which in vivo is supplied by the cytoplasm. This cooperation was simulated in vitro by adding all enzymes and cofactors necessary for conversion of 3-phosphoglycerate into UDP-galactose to intact chloro­ plasts which then formed labelled monogalactosyl diacylglycerol from labelled C 0 2 . The time required to transfer envelope-made galactolipids from the envelope into thylakoids was studied by incubating intact chloroplasts with radioactive UDP-galactose, subsequent osmotic disruption of organelles with concomitant enzymatic degradation o f UDP-galactose followed by separation o f envelopes and thylakoids. Only after short times (< 1 min) appreciable pro­ portions (20 -30%) o f radioactive galactolipids were recovered in the envelope fraction. This in combination with previous results indicates a rapid galactolipid export from envelopes into thylakoids. 
  Reference    Z. Naturforsch. 36c, 62 (1981); received September 16 1980 
  Published    1981 
  Keywords    Acyl-CoA, UDP-Galactose, Envelope, Impermeability, Lipid Transport 
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 TEI-XML for    default:Reihe_C/36/ZNC-1981-36c-0062.pdf 
 Identifier    ZNC-1981-36c-0062 
 Volume    36 
3Author    K.H G Rum BachRequires cookie*
 Title    Distribution of Chlorophylls, Carotenoids and Quinones in Chloroplasts of Higher Plants  
 Abstract    Leaves, cotyledons, isolated chloroplasts and subplastid fractions (thylakoids and envelopes) o f radish (Raphanus sativus L. cv. Saxa) and spinach (Spinacia oleracea L. cv. M atador) were assayed for their pigment and quinone content and com position. Virtually all the chlorophylls, carotenoids and quinones were contained in the thylakoids. Envelopes prepared by the method described contained very low amounts o f chlorophyll a and b, violaxanthin and neoxanthin, but no /7-carotene, lutein, zeaxanthin and antheraxanthin. Am ong the quinones trace am ounts o f plastoquinone and a-tocopherol but no plastohydroquinone, a-tocoquinone and phylloquinone were detected. Presented data may be taken as evidence that in vivo the chloroplast envelope is not a location site o f carotenoids and quinones as generally accepted. Possible im plications for the biosyntheses o f quinones and pigments are discussed. 
  Reference    Z. Naturforsch. 38c, 996—1002 (1983); received August 16 1983 
  Published    1983 
  Keywords    Carotenoids, Chlorophylls, Chloroplasts, Envelopes, Quinones, Thylakoids 
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 TEI-XML for    default:Reihe_C/38/ZNC-1983-38c-0996.pdf 
 Identifier    ZNC-1983-38c-0996 
 Volume    38 
4Author    Christine Schindler, Ruth Hracky, Jürgen SollRequires cookie*
 Title    Protein Transport in Chloroplasts: ATP is Prerequisit  
 Abstract    The energy requirem ent for protein transport into chloroplast was assayed under conditions that perm it to distinguish whether the posttranslational translocation is dependent on A TP or w hether a m em brane potential across the chloroplast envelope can drive this transport event. A m em brane potential is not required for translocation. A TP can support protein transport in the presence of protonophores and ionophores. Non-hydrolyzable A TP analogues and G TP, CTP, U T P cannot serve as ATP substitutes. Translocation could be observed when an A TP generating system was used to supply ATP. In contrast ATP degrading systems completely abolished translocation. The inner envelope mem brane localized ATP-ase is probably not involved in the transport event. The results suggest that ATP is needed at the outer chloroplast envelope. Inhibition of protein transport by A D P , pyrophosphate and NaF is studied and its con­ sequences discussed. 
  Reference    Z. Naturforsch. 42c, 103 (1987); received August 26 1986 
  Published    1987 
  Keywords    Protein T ransport, ATP-Hydrolysis, Chloroplasts, Envelope, Pisum sativum 
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 TEI-XML for    default:Reihe_C/42/ZNC-1987-42c-0103.pdf 
 Identifier    ZNC-1987-42c-0103 
 Volume    42