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1Author    E. K. Pistorius, G. H. SchmidRequires cookie*
 Title    Studies on the O2 Evolution under Flash Light Illumination in Preparations of A nacystis nidulans  
 Abstract    The 0 2 yield under flash light illum ination in preparations o f Anacystis nidulans was exam ined in the presence o f redox components such as ferricyanide and ferrocyanide. W hen ferricyanide (1 mM) was added to the lyophilized, lysozym e treated and ED TA w ashed cells o f A. nidulans the familiar Joliot-Kok oscillalion with m axim um on the third flash and periodicity o f four was observed (in the presence o f added CaCl2 and M nCl2). H owever, when the ferricyanide con­ centration was increased to about 8 m M , a reduction o f the 0 2 evolution under flash illum ination was observed, and an 0 2 uptake could clearly be seen under the First and second flash. This 0 2 uptake was inhibited by D C M U and o-phenanthroline, but was not influenced by KCN or salicylhydroxamic acid. As ferrocyanide was progressively added to 1 m M ferricyanide, the oscillations faded out and the steady-state 0 2 evolution decreased. Light would progressively increase the 0 2 evolution and reduce the dam ping o f the oscillations. Two patterns o f 0 2 evolution under short saturating light flashes were observed with these Anacystis preparations on first illum ination in the presence o f cations but in the absence o f ferri­ cyanide. One pattern corresponded to the typical pattern w hich has been repeatedly described in the literature, but the second pattern gave the indication o f an initial "over-reduced" state o f the photosystem II reaction center. W ith suitable procedures the two patterns were interchangeable. Moreover, the effect o f L-arginine on the flash pattern was exam ined. The results are discussed in connection with the possible dual function o f the previously described flavin protein as an L-amino acid oxidase and as a com ponent o f the 0 2 evolving reaction center (E. K. Pistorius and H. Voss, Eur. J. Biochemistry 1 2 6 ,2 0 3 -2 0 9 (1982)). 
  Reference    Z. Naturforsch. 39c, 1097—1103 (1984); received August 20 1984 
  Published    1984 
  Keywords    0 2 Evolution, Photosystem II, Cyanobacteria, A nacystis nidulans 
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 TEI-XML for    default:Reihe_C/39/ZNC-1984-39c-1097.pdf 
 Identifier    ZNC-1984-39c-1097 
 Volume    39 
2Author    ElfriedeK. PistoriusRequires cookie*
 Title    Further Evidence for a Functional Relationship between L-Amino Acid Oxidase Activity and Photosynthetic Oxygen Evolution in Anacystis nidulans. Effect of Chloride on the Two Reactions  
 Abstract    The L-amino acid oxidase from Anacystis nidulans is inhibited by cations as well as anions. The inhibition by cations has been previously described (E. K. Pistorius, Eur. J. Biochem. 135, 217—222 [1983]). We have shown that the order of effectiveness was > M2+ > M +, when e.g. La3+, Ca2+ and K+ were compared. However, in the concentration range where the monovalent cations inhibited, the inhibition was not entirely due to the cation, but an influence of the anion could also be observed. When monovalent anions were compared as the corresponding sodium salts, the order of effectiveness was SCN~ > N 0 3_ > CL, Br > I~ > F ' > H CO O " > CH,COO . The inhibition of the L-amino acid oxidase activity by the various salts was strongly influenced by the pH of the reaction mixture. It could be shown that the inhibition by cations increased in the alkaline pH region, while the inhibition by anions increased in the acidic pH region. Our previous results have also shown that a functional relationship might exist between L-amino acid oxidase activity and photosynthetic 0 2 evolution (E. K. Pistorius and H. Voss, Eur. J. Biochem. 126, 203—209 [1982]). Since the water-splitting complex of photosystem II is affected by a number of anions, although only Cl-and Br" lead to activation of 0 2 evolution, we investigated whether a correlation could be obtained between the anion effect on the L-amino acid oxidase and on photosynthetic 0 2 evolution. The results show that those anions which have a higher affinity for the enzyme than CL or Br", are especially effective in causing inactivation of the 0 2 evolu­ tion. Moreover, we show that L-arginine which is a substrate of the L-amino acid oxidase, and Cl-have antagonistic effects on the L-amino acid oxidase reaction and on photosynthetic 0 2 evolu­ tion. We suggest that this flavoprotein with L-amino acid oxidase activity is modified by Ca:+ and CL in such a way that it can now interact with Mn2* and catalyze the water-splitting reaction of photosystem II. 
  Reference    Z. Naturforsch. 40c, 806—813 (1985); received June 7 1985 
  Published    1985 
  Keywords    Anacystis nidulans, 0 2 Evolution, L-Amino Acid Oxidase, Chloride 
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 TEI-XML for    default:Reihe_C/40/ZNC-1985-40c-0806.pdf 
 Identifier    ZNC-1985-40c-0806 
 Volume    40 
3Author    T. Fujim, F. Yoshii, I. Kaetsu, Y. Inoue, K. ShibataRequires cookie*
 Title    Effect of Irradiation and Immobilization on Spinach Chloroplast Activities  
 Abstract    The effect of y-ray irradiation and immobilization by means of radiation polymerization on PS II activity (0 2 evolution) o f isolated chloroplasts from spinach was investigated. Reduction o f 0 2 evolution activity by irradiation was small at lower temperatures below — 24 °C, but the activity decreased slightly by freezing at extremely low temperature below —78 °C. So the optimum low temperature range for the treatment was observed. The immobilized chloroplast in a hydrophilic polymer matrix showed the stable duration o f 0 2 evolution activity more than 700 h at 4 °C . Thermo-stability o f chloroplast was also improved greatly by immobilization. The active center o f PS II in immobilized chloroplasts was retained even after 60 min standing at 50 °C. 
  Reference    Z. Naturforsch. 35c, 477—481 (1980); received February 12 1980 
  Published    1980 
  Keywords    Radiation Effect, Chloroplast, 0 2 Evolution, Immobilization, Radiation Polymerization, Low Temperatures 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-0477.pdf 
 Identifier    ZNC-1980-35c-0477 
 Volume    35 
4Author    K. Burda, G. H. SchmidRequires cookie*
 Title    On the Determination of the 5-State Distribution in the Kok Model  
 Abstract    We use the Markow chain theory to analyze the oscillation pattern of oxygen evolution during water oxidation in photosystem II under short saturating light flashes. We propose a method based on the standard least square deviation (test x 2) to determine the number of 5-states in the Kok model. As pointed out by Burda et al. (1995) this information is amongst others important for the interpretation of the role of calcium for oxygen evolution. A specific mathematical representation for a situation when the S4 state is longer living than generally assumed is introduced which requires an explicit extension of the Kok model to five states. The higher stability is modelled by introducing additional decay channels, e.g. a nonvanishing probability for the transition of S3 to the 5() state and a further transition probability for the transition from S3 to 5 4. Our analysis is extended to the case of damped oscillations of oxygen evolution caused, for example, by the lack of electron acceptor or the short life time of photosystem II particles. 
  Reference    Z. Naturforsch. 51c, 329—341 (1996); received O ctober 23/D ecem ber 5 1995 
  Published    1996 
  Keywords    0 2-Evolution, o-and ^-Analysis, Transition Probabilities, Cyanobacteria, Tobacco, Chlorella 
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 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0329.pdf 
 Identifier    ZNC-1996-51c-0329 
 Volume    51