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You searched for subject:(Tyrosine Z). Showing records 1 – 3 of 3 total matches.

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1. Chrysina, Maria. Συνεργασία μεταλλικού συμπλόκου - ρίζας κατά τη φωτοσυνθετική διάσπαση του H2O.

Degree: 2015, National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ)

Photosystem II is a membrane multi - subunit protein complex, whichcatalyzes the photoinduced water oxidation in plants. When a special cluster ofchlorophylls, P680, absorbs a photon, it gives an electron to plastoquinone Q. Thepositive charge on P680 is compensated by an electron from a Mn4CaO5 cluster,which binds substrate H2O molecules. When four photons are absorbed, fourelectrons have moved from the Mn4CaO5 cluster to quinone and four H+have been released to the bulk, then O2 is formed. Therefore, the catalytic cycle of the Mn4CaO5cluster undergoes four transitions, called S – transitions: S0 → S1, S1 → S2, S2 → S3, S3→ (S4) → S0. TyrΗ, a residue near Mn4CaO5, acts as an intermediate electron carrierbetween the cluster and P680, and in parallel it influences H+removal.In the present work, low-temperature EPR spectroscopy was employed inorder to trap and study intermediates, including the free radical TyrΗ˙ interactingwith Mn4CaΟ5, during the two critical transitions S2 → S3 and S3 → S0. When S2TyrΗ˙ istrapped at temperatures > ca 233 K, proton abstraction is in progress, in constrast totrapping at cryogenic temperature, at which proton remains at its site. During S2 →S3, TyrZ abstracts simultaneously eand Θ+from Mn4CaO5 and the H bond networkincluding Asn 298 is used for proton extraction. At S3 → S0, the Asp 61 pathway isused. In the presence of methanol, the Asp 61 pathway is used in S2 → S3. In order toproceed to S3, methanol has to be exchanded with a Θ2Ο molecule. The criticalintermediate S3TyrΗ˙ was trapped, and this is important for understanding O2formation during S3 → S0. Finally, the methodology used in the present study will bevery useful in the trapping of unstable intermediates and related studies by advanced spectroscopic techniques.

Subjects/Keywords: Φωτοσύνθεση; Διάσπαση H2D; Φωτοσύστημα ΙΙ; Τυροσίνη Ζ; Σύμπλοκο Mn4CaO5; S - μεταβάσεις; Photosynthesis; Water oxidation; Photosystem II; Tyrosine Z; Mn4CaO5 complex; S - transitions

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APA (6th Edition):

Chrysina, M. (2015). Συνεργασία μεταλλικού συμπλόκου - ρίζας κατά τη φωτοσυνθετική διάσπαση του H2O. (Thesis). National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ). Retrieved from http://hdl.handle.net/10442/hedi/44157

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Chrysina, Maria. “Συνεργασία μεταλλικού συμπλόκου - ρίζας κατά τη φωτοσυνθετική διάσπαση του H2O.” 2015. Thesis, National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ). Accessed September 19, 2020. http://hdl.handle.net/10442/hedi/44157.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Chrysina, Maria. “Συνεργασία μεταλλικού συμπλόκου - ρίζας κατά τη φωτοσυνθετική διάσπαση του H2O.” 2015. Web. 19 Sep 2020.

Vancouver:

Chrysina M. Συνεργασία μεταλλικού συμπλόκου - ρίζας κατά τη φωτοσυνθετική διάσπαση του H2O. [Internet] [Thesis]. National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ); 2015. [cited 2020 Sep 19]. Available from: http://hdl.handle.net/10442/hedi/44157.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Chrysina M. Συνεργασία μεταλλικού συμπλόκου - ρίζας κατά τη φωτοσυνθετική διάσπαση του H2O. [Thesis]. National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ); 2015. Available from: http://hdl.handle.net/10442/hedi/44157

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

2. Keough, James M. Redox active tyrosines in photosystem II: role in proton coupled electron transfer reactions.

Degree: PhD, Chemistry and Biochemistry, 2013, Georgia Tech

Proton coupled electron transfer reactions often involve tyrosine residues, because when oxidized, the phenolic side chain deprotonates. Tyrosine Z (YZ) is responsible for extracting electrons in a stepwise fashion from the oxygen evolving-complex in order to build enough potential to oxidize water. This process requires that each step YZ must deprotonate and reprotonate in order to maintain the high midpoint potential that is necessary to oxidize the oxygen-evolving complex, which makes YZ highly involved in proton coupled electron transfer reactions. In this thesis YZ has been studied within oxygen-evolving photosystem II utilizing electron paramagnetic resonance spectroscopy to monitor the tyrosyl radical that is formed upon light excitation. Kinetic analysis of YZ has shed light on the factors that are important for PSII to carry out water oxidation at the oxygen-evolving complex. Most notably the strong hydrogen-bonding network and the midpoint potential of YZ have been shown to be integral aspects of the water splitting reactions of PSII. By studying YZ within oxygen-evolving PSII, conclusions are readily applied to the native system. Advisors/Committee Members: Bridgette A. Barry (Committee Chair), Adegboyega K. Oyelere (Committee Member), Facundo Fernandez (Committee Member), Ingeborg Schmidt-Krey (Committee Member), Mostafa El-Sayed (Committee Member).

Subjects/Keywords: Photosystem II; Proton coupled electron transfer reactions; Tyrosine Z; Tyrosine D; YZ; YD; Water oxidation; Photosynthesis; Power resources Research; Photosynthetic reaction centers

…Chlorophyll a Chl Chlorophyll P680 Oxidant to tyrosine Z xiii P680+ Oxidized form of the… …oxidant to tyrosine Z PCET Proton coupled electron transfer PTET Proton transfer followed by… …evolving complex SnYZ Tyrosine Z in the Sn state (n = 0-4) SnYZ• Neutral radical of… …tyrosine Z in the Sn state (n = 0-4) KIE pL Kinetic isotope effect (defined as… …deprotonates. Tyrosine Z (YZ) is responsible for extracting electrons in a stepwise fashion… 

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Keough, J. M. (2013). Redox active tyrosines in photosystem II: role in proton coupled electron transfer reactions. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/47738

Chicago Manual of Style (16th Edition):

Keough, James M. “Redox active tyrosines in photosystem II: role in proton coupled electron transfer reactions.” 2013. Doctoral Dissertation, Georgia Tech. Accessed September 19, 2020. http://hdl.handle.net/1853/47738.

MLA Handbook (7th Edition):

Keough, James M. “Redox active tyrosines in photosystem II: role in proton coupled electron transfer reactions.” 2013. Web. 19 Sep 2020.

Vancouver:

Keough JM. Redox active tyrosines in photosystem II: role in proton coupled electron transfer reactions. [Internet] [Doctoral dissertation]. Georgia Tech; 2013. [cited 2020 Sep 19]. Available from: http://hdl.handle.net/1853/47738.

Council of Science Editors:

Keough JM. Redox active tyrosines in photosystem II: role in proton coupled electron transfer reactions. [Doctoral Dissertation]. Georgia Tech; 2013. Available from: http://hdl.handle.net/1853/47738

3. ΜΠΑΚΟΥ, ΑΛΕΞΑΝΔΡΑ. ΜΕΛΕΤΗ ΤΩΝ ΘΕΣΕΩΝ ΔΕΣΜΕΥΣΗΣ ΤΩΝ ΙΟΝΤΩΝ ΑΣΒΕΣΤΙΟΥ ΣΤΟ ΦΩΤΟΣΥΣΤΗΜΑ ΙΙ ΜΕ ΧΡΗΣΗ ΤΡΙΣΘΕΝΩΝ ΙΟΝΤΩΝ ΛΑΝΘΑΝΙΔΙΩΝ.

Degree: 1995, Πανεπιστήμιο Κρήτης; University of Crete (UOC)

ΤΑ ΙΟΝΤΑ CA++ ΤΟΥ ΦΩΤΟΣΥΣΤΗΜΑΤΟΣ ΙΙ ΑΝΤΙΚΑΤΑΣΤΑΘΗΚΑΝ ΑΠΟ ΔΙΑΦΟΡΑ ΠΑΡΑΜΑΓΝΗΤΙΚΑ ΚΑΙ ΔΙΑΜΑΓΝΗΤΙΚΑ ΙΟΝΤΑ ΛΑΝΘΑΝΙΔΙΩΝ (LN3+) ΣΕ ΜΕΜΒΡΑΝΕΣ PS II ΠΟΥ ΑΠΟΜΟΝΩΘΗΚΑΝ ΑΠΟ ΣΠΑΝΑΚΙ. Η ΕΠΙΔΡΑΣΗ ΤΩΝ ΤΡΙΣΘΕΝΩΝ ΤΟΥΤΩΝ ΛΑΝΘΑΝΙΔΙΩΝ ΣΤΙΣ ΚΑΤΑΛΥΤΙΚΕΣ ΚΑΙ ΔΟΜΙΚΕΣ ΙΔΙΟΤΗΤΕΣ ΤΟΥ ΦΩΤΟΣΥΣΤΗΜΑΤΟΣ ΙΙ ΜΕΛΕΤΗΘΗΚΕ ΜΕ ΦΑΣΜΑΤΟΣΚΟΠΙΑ ΗΛΕΚΤΡΟΝΙΚΟΥ ΠΑΡΑΜΑΓΝΗΤΙΚΟΥ ΣΥΝΤΟΝΙΣΜΟΥ (EPR) ΚΑΙ ΟΠΤΙΚΗ ΦΑΣΜΑΤΟΣΚΟΠΙΑ ΔΙΑΦΟΡΑΣ ΑΠΟΡΡΟΦΗΣΗΣ. Η ΜΕΛΕΤΗ ΜΕ ΚΙΝΗΤΙΚΗ ΦΑΣΜΑΤΟΣΚΟΠΙΑ EPR ΑΠΕΔΕΙΞΕ ΟΤΙ Η ΠΑΡΟΥΣΙΑ ΤΩΝ ΛΑΝΘΑΝΙΔΙΩΝ ΣΤΙΣ ΘΕΣΕΙΣ ΔΕΣΜΕΥΣΗΣ ΤΟΥ ΑΣΒΕΣΤΙΟΥ ΣΤΟ ΦΩΤΟΣΥΣΤΗΜΑ ΙΙ ΕΠΗΡΕΑΖΕΙ, ΕΚΤΟΣ ΤΗΣ ΗΛΕΚΤΡΟΝΙΑΚΗΣ ΜΕΤΑΦΟΡΑΣ ΑΠΟ ΤΟ ΣΥΜΠΛΟΚΟ ΤΟΥ ΜΑΓΓΑΝΙΟΥ ΣΤΗ ΡΙΖΑ TYR-Z+ ΚΑΙ ΤΗ ΜΕΤΑΦΟΡΑ ΗΛΕΚΤΡΟΝΙΩΝ ΑΠΟ ΤΗΝ ΤΥΡΟΣΙΝΗ Ζ ΣΤΗΝ ΟΞΕΙΔΩΜΕΝΗ ΧΛΩΡΟΦΥΛΛΗ P+680. Η ΤΕΛΕΥΤΑΙΑ ΕΠΙΔΡΑΣΗ ΕΞΑΡΤΑΤΑΙ ΑΠΟ ΤΗΝ ΙΟΝΤΙΚΗ ΑΚΤΙΝΑ ΤΩΝ ΙΟΝΤΩΝ LN3+ ΚΑΙ ΤΟ PH ΤΟΥ ΣΥΣΤΗΜΑΤΟΣ. Η ΕΠΙΔΡΑΣΗ ΤΩΝ LN3+ ΣΤΗΝ ΑΝΑΓΩΓΗ ΤΩΝ P+680 ΑΠΟ ΤΗΝ TYR-Z ΠΑΡΑΤΗΡΕΙΤΑΙ ΣΕ PH 6 ΑΛΛΑ ΟΧΙ ΣΕ PH 7,5. ΤΑ ΠΕΙΡΑΜΑΤΙΚΑ ΑΠΟΤΕΛΕΣΜΑΤΑ ΤΗΣ ΜΕΛΕΤΗΣ ΜΕ ΟΠΤΙΚΗ ΦΑΣΜΑΤΟΣΚΟΠΙΑ ΔΙΑΦΟΡΑΣ ΑΠΟΡΡΟΦΗΣΗΣ ΘΕΩΡΗΘΗΚΑΝ ΩΣ ΕΝΔΕΙΞΗ ΟΤΙ ΤΟ P+680 ΑΝΑΓΕΤΑΙ ΑΠΟ ΕΝΑΝ ΕΝΑΛΛΑΚΤΙΚΟ ΔΟΤΗ ΣΕ PH 6,0.

A SELECTIVE SUBSTITUTION OF CA2+ BY VARIOUS PARAMAGNETIC AND DIAMAGNETIC LANTHANIDE IONS (LN3+) WAS CARRIED OUT IN PHOTOSYSTEM II MEMBRANES FROM SPINACH. THE EFFECT OF THE TRIVALENT LANTHANIDE IONS ON THE STRUCTURAL AND CATALYTIC PROPERTIES OF PHOTOSYSTEM II WAS STUDIED BY USING ELECTRON PARAMAGNETIC RESONANCE (EPR) AND ABSORBANCE DIFFERENCE OPTICAL SPECTROSCOPY. IN ADDITION TO BLOCKINGELECTRON TRANSPORT FROM THE MN-COMPLEX TO TYR-Z, THE PRESENCE OF LANTHANIDESIN THE CALCIUM BINDING SITES IN PS II AFFECTS ELECTRON TRANSPORT FROM THE TYROSINE Z TO THE OXIDIZED CHLOROPHYL P+680. THE LATTER EFFECT DEPENDS ON BOTH THE IONIC RADII OF TRIVALENT LANTHANIDE IONS AND TH PH OF THE SYSTEM. ALTHOUGH THE PRESENCE OF THE LANTHANIDES HAS A STRONG INFLUENCE ON THE REDUCTION OF P+680 BY TYROSINE Z AT PH 6.0, NO SUCH EFFECT IS OBSERVED AT PH 7,5. A STUDY OF THE LANTHANIDE TREATED PS II BY ABSORBANCE DIFFERENCE SPECTROSCOPY IMPLIED THAT P+680 MIGHT BE REDUCED BY AN ALTERNATIVE DONOR AT PH 6.0.

Subjects/Keywords: ABSORBANCE DIFFERENCE OPTICAL SPECTROSCOPY; CALCIUM IONS (CA++); CHLOROPHYL P680; ELECTRON PARAMAGNETIC RESONANCE SPECTROSCOPY (EPR); ELECTRON TRANSPORT; LANTHAMIDE IONS (LN3+); MN-COMPLEX; Photosystem II (PSII); TYROSINE Z (TYR-Z); ΗΛΕΚΤΡΟΝΙΑΚΗ ΜΕΤΑΦΟΡΑ; ΙΟΝΤΑ ΑΣΒΕΣΤΙΟΥ (CA++); ΙΟΝΤΑ ΛΑΝΘΑΝΙΔΙΩΝ (LN3+); ΟΠΤΙΚΗ ΦΑΣΜΑΤΟΣΚΟΠΙΑ ΔΙΑΦΟΡΑΣ ΑΠΟΡΡΟΦΗΣΗΣ; ΣΥΜΠΛΟΚΟ ΤΟΥ ΜΑΓΓΑΝΙΟΥ; ΤΥΡΟΣΙΝΗ Ζ; Φασματοσκοπία ηλεκτρονικού παραμαγνητικού συντονισμού; Φωτοσύστημα PS (II); ΧΛΩΡΟΦΥΛΛΗ Ρ680

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

ΜΠΑΚΟΥ, . (1995). ΜΕΛΕΤΗ ΤΩΝ ΘΕΣΕΩΝ ΔΕΣΜΕΥΣΗΣ ΤΩΝ ΙΟΝΤΩΝ ΑΣΒΕΣΤΙΟΥ ΣΤΟ ΦΩΤΟΣΥΣΤΗΜΑ ΙΙ ΜΕ ΧΡΗΣΗ ΤΡΙΣΘΕΝΩΝ ΙΟΝΤΩΝ ΛΑΝΘΑΝΙΔΙΩΝ. (Thesis). Πανεπιστήμιο Κρήτης; University of Crete (UOC). Retrieved from http://hdl.handle.net/10442/hedi/3441

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

ΜΠΑΚΟΥ, ΑΛΕΞΑΝΔΡΑ. “ΜΕΛΕΤΗ ΤΩΝ ΘΕΣΕΩΝ ΔΕΣΜΕΥΣΗΣ ΤΩΝ ΙΟΝΤΩΝ ΑΣΒΕΣΤΙΟΥ ΣΤΟ ΦΩΤΟΣΥΣΤΗΜΑ ΙΙ ΜΕ ΧΡΗΣΗ ΤΡΙΣΘΕΝΩΝ ΙΟΝΤΩΝ ΛΑΝΘΑΝΙΔΙΩΝ.” 1995. Thesis, Πανεπιστήμιο Κρήτης; University of Crete (UOC). Accessed September 19, 2020. http://hdl.handle.net/10442/hedi/3441.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

ΜΠΑΚΟΥ, ΑΛΕΞΑΝΔΡΑ. “ΜΕΛΕΤΗ ΤΩΝ ΘΕΣΕΩΝ ΔΕΣΜΕΥΣΗΣ ΤΩΝ ΙΟΝΤΩΝ ΑΣΒΕΣΤΙΟΥ ΣΤΟ ΦΩΤΟΣΥΣΤΗΜΑ ΙΙ ΜΕ ΧΡΗΣΗ ΤΡΙΣΘΕΝΩΝ ΙΟΝΤΩΝ ΛΑΝΘΑΝΙΔΙΩΝ.” 1995. Web. 19 Sep 2020.

Vancouver:

ΜΠΑΚΟΥ . ΜΕΛΕΤΗ ΤΩΝ ΘΕΣΕΩΝ ΔΕΣΜΕΥΣΗΣ ΤΩΝ ΙΟΝΤΩΝ ΑΣΒΕΣΤΙΟΥ ΣΤΟ ΦΩΤΟΣΥΣΤΗΜΑ ΙΙ ΜΕ ΧΡΗΣΗ ΤΡΙΣΘΕΝΩΝ ΙΟΝΤΩΝ ΛΑΝΘΑΝΙΔΙΩΝ. [Internet] [Thesis]. Πανεπιστήμιο Κρήτης; University of Crete (UOC); 1995. [cited 2020 Sep 19]. Available from: http://hdl.handle.net/10442/hedi/3441.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

ΜΠΑΚΟΥ . ΜΕΛΕΤΗ ΤΩΝ ΘΕΣΕΩΝ ΔΕΣΜΕΥΣΗΣ ΤΩΝ ΙΟΝΤΩΝ ΑΣΒΕΣΤΙΟΥ ΣΤΟ ΦΩΤΟΣΥΣΤΗΜΑ ΙΙ ΜΕ ΧΡΗΣΗ ΤΡΙΣΘΕΝΩΝ ΙΟΝΤΩΝ ΛΑΝΘΑΝΙΔΙΩΝ. [Thesis]. Πανεπιστήμιο Κρήτης; University of Crete (UOC); 1995. Available from: http://hdl.handle.net/10442/hedi/3441

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

.