Deconvolution of ferredoxin, plastocyanin, and P700 transmittance changes in intact leaves with a new type of kinetic LED array spectrophotometer Christof Klughammer1 • Ulrich Schreiber1 Received: 24 September 2015/Accepted: 11 January 2016/Published online: 2 February 2016 The Author(s) 2016. Also, plastocyanin is dependent on copper, while plastoquinone is not dependent on copper. (2000) The Protein Data Bank. Both proteins were present in cells grown in 0.3 MM copper. Obviously, there exist a number of internal discrepancies within the studies on the Chlamydomonas mutants which must be settled before these mutant forms can be so indiscriminately and authoritatively employed to localize the site of action of plastocyanin. The Arabidopsis ortholog of C. reinhardtii CRR1, SPL7, functions to spare Cu for plastocyanin by replacing CuZnSOD with an FeSOD (Pilon et al., 2009). Electrons enter and leave PC via the H87 ligand to the copper, which is located on the surface of the PC molecule (Figures 1 and 2). Metal–ligand bond distances of blue and green copper centers (Å). In addition, these rods have been shown to switch between two spectrally different conformations (with maxima at 651 or at 672 nm). The protein is monomer, with a molecular weight around 10,000 Daltons, and 99 amino acids in most vascular plants. Table 4. can use two different electron donors to PS I: Biochimica et Biophysica Acta (BBA) - Bioenergetics, Plastocyanin, electron transfer in plastid, CoproporphyrinogenIII oxidase, plastid heme synthesis, Coproporphyrinogen III oxidase, plastid heme synthesis, Aerobic oxidative cyclase, tetrapyrrole biosynthetic pathway, Transcription factor, regulation of Cu deficiency response. Evidently, there is a connection to anaerobiosis because CRR1 and its target genes are also required in situations of low O2 tension in C. reinhardtii (Quinn et al., 2002; Eriksson et al., 2004). Biochemical characterization of the two proteins purified from several cyanobacteria indicated that their pIs (which ranged from 4 to 9) covaried, suggesting that they were coevolving in response to changes in common reaction partners (Ho and Krogmann, 1984). This spectrophotometer is used in the present work for in vitro light-induced measurements with various combinations of photosystem I (PSI) from tobacco and two different cyanobacteria, spinach plastocyanin, cyanobacterial cytochrome c 6 (cyt. (1972) demonstrated rather convincingly that plastocyanin is present both in the grana and the stroma membranes of spinach chloroplasts. Contains two copper atoms per molecule. Page and S. S. Merchant, unpublished). 2001 Plastocyanin is a blue copper protein that was isolated from plant leaves because of its abundance and spectroscopic properties (Katoh and Takamiya, 1961). Fragmentation of chloroplasts by passage through a French-press and subsequent differential centrifuga-tion for the isolation of grana and stroma lamellae has been described previously3. Copyright © 2021 Elsevier B.V. or its licensors or contributors. Moreover, plastoquinone is present in inner thylakoid membrane, while plastocyanin is present in the thylakoid lumen. We use cookies to help provide and enhance our service and tailor content and ads. Summary The PSI‐N subunit of photosystem I (PSI) is restricted to higher plants and is the only subunit located entirely in the thylakoid lumen. The lower Cu requirements of pcy1 mutants give an indication of the large contribution of plastocyanin to the cellular Cu quota (Hill and Merchant, 1992). Wikipedia. The PsaG subunit in plants forms an anchoring point for the Lhca subunits of the PSI peripheral antenna, while the subunit PsaH, together with PsaL and PsaK, have been shown to play important roles in state transitions in plants and green algae (see, e.g., Kouřil et al., 2005; Zhang and Scheller, 2004). The electron transport protein plastocyanin is present in the lumen and shuttles electrons from the cytochrome b6f protein complex to photosystem I.