Abstract
A new binding site for anions which inhibit the water oxidizing complex (WOC) of Photosystem II in spinach has been identified. Anions which bind to this site inhibit the flash-induced S2/S0 catalase reaction (2H2O2→2H2O+O2) of the WOC by displacing hydrogen peroxide. Using a mass spectrometer and gas permeable membrane to detect the 32O2 product, the yield and lifetime of the active state of the flash-induced catalase (to be referred to simply as ‘flash-catalase’) reaction were measured after forming the S2 or S0-states by a short flash. The increase in flash-catalase activity with H2O2 concentration exhibits a Km=10–20 mM, and originates from an increase in the lifetime by 20-fold of the active state. The increased lifetime in the presence of peroxide is ascribed to formation of the long-lived S0-state at the expense of the unstable S2-state. The anion inhibition site differs from the chloride site involved in stimulating the photolytic water oxidation reaction (2H2O→O2+4e-+4H+). Whereas water oxidation requires Cl- and is inhibited with increasing effectiveness by F-≪CN-≪N3 -, the flash-catalase reaction is weakly inhibited by Cl-, and with increasing effectiveness by F-≪CN-, N3 -. Unlike water oxidation, chloride is unable to suppress or reverse inhibition of the flash-catalase reaction caused by these anions. The inhibitor effectiveness correlates with the pKa of the conjugate acid, suggesting that the protonated species may be the active inhibitor. The reduced activity arises from a shortening of the lifetime of the flash-induced catalase active state by 3–10 fold owing to stronger anion binding in the flash-induced states, S2 and S0, than in the dark S-states, S1 and S-1. To account for the paradoxical result that higher anion concentrations are required to inhibit at lower H2O2 concentrations, where S2 forms initially after the flash, than at higher H2O2 concentrations, where S0 forms initially after the flash, stronger anion binding to the S0-state than to the S2-state is proposed. A kinetic model is given which accounts for these equilibria with anions and H2O2. The rate constant for the formation/release of O2 by reduction of S2 in the WOC is <0.4 s-1.
Similar content being viewed by others
Abbreviations
- ADRY:
-
acceleration of the deactivation reactions of the water splitting enzyme system Y
- BTP:
-
bis [tris(hydroxymethyl)methylamino]-propane
- CCCP:
-
carbonylcyanide m-chlorophenylhyrazone
- DCBQ:
-
2,5-dichlorobenzoquinone
- DMBQ:
-
2,3-dimethylbenzoquinone
- WOC:
-
water oxidizing complex
References
Ananyev G, Wydrzynski T, Renger G and Klimov V (1992) Transient peroxide formation by the manganese-containing, redox-active donor side of Photosystem II upon inhibition of O2 evolution with lauroylchlorine chloride. Biochim Biophys Acta 1100: 303–311
Asada K (1992) Ascorbate peroxidase — a hydrogen peroxide scavenging enzyme in plants. Physiol Plant. 85: 235–241
Fine PL and Frasch WD (1992) The oxygen-evolving complex requires chloride to prevent hydrogen peroxide formation. Biochemistry 31: 12204–12210
Frasch WD and Mei R (1987a) Hydrogen peroxide as an alternative substrate for the oxygen-evolving complex. Biochim Biophys Acta 891: 8–14
Frasch WD and Mei R (1987b) Kinetics of O2 evolution from H2O2 catalyzed by the oxygen-evolving complex: Investigation of the S1-dependent reaction. Biochemistry 26: 7321–7325
Ghanotakis DF, Babcock GT and Yocum CF (1985) La3+ competes with Ca2+ for binding to the oxidizing side of Photosystem II. Biochim Biophys Acta 809: 173–180
Ghanotakis DF, Demetriou DM and Yocum CF (1987) Isolation and characterization of an oxygen-evolving Photosystem II reaction center core preparation and a 28 kDa Chl-a-binding protein. Biochim Biophys Acta 891: 15–21
Homann P (1988) The chloride and calcium requirement of photosynthetic water oxidation: Effects of pH. Biochim Biophys Acta 934: 244–248
Jegerschöld C, Virgin I and Styring S (1990) Light-dependent degradation of the D1 protein in Photosystem II is accelerated after inhibition of the water splitting reaction. Biochemistry 29: 6179–6184
Joliot P, Hofnung M and Chabaud R (1966) Étude de l'émission d'oxygène par des algues soumises a un éclairement modulé sinusoidalement. J Chim Phys 63: 1423–1441
Kok B, Forbush B and McGloin M (1970) Cooperation of changes in photosynthetic oxygen evolution-I. A linear four step mechanism. Photochem Photobiol 11: 457
Mano J, Takahashi M and Asada K (1987) Oxygen evolution from hydrogen peroxide in Photosystem II: Flash-induced catalatic activity of water-oxidizing Photosystem II membranes. Biochemistry 26: 2495–2501
Radmer R and Ollinger O (1986) Do the higher oxidation states of the photosynthetic O2-evolving system contain bound H2O? FEBS Lett 195: 285–287
Sandusky PO and Yocum CF (1988) Hydrogen peroxide oxidation catalyzed by chloride-depleted thylakoid membranes. Biochim Biophys Acta 936: 149–156
Sivaraja M, Tso J and Dismukes GC (1989) A comparison of the manganese center responsible for photosynthetic water oxidation in O2-evolving core particles and Photosystem II enriched membranes: EPR of the S2-state. Isr J Chem 28: 103–108
Styring S and Rutherford AW (1987) In the oxygen-evolving complex of PS II the S0-state is oxidized to the S1-state by D+. Biochemistry 26: 2401–2405
Vass I, Deak Z and Hideg E (1990) Charge equilibrium between the water-oxidizing complex and the electron donor tyrosine-D in PS II. Biochim Biophys Acta 1017: 63–69
Velthuys B and Kok B (1978) Photosynthetic oxygen evolution from hydrogen peroxide. Biochim Biophys Acta 502: 211–221
Vermaas WF, Renger G and Dohnt G (1984) The reduction of the oxygen-evolving system in chloroplasts by thylakoid components. Biochim Biophys Acta 764: 194–202
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Mano, J., Kawamoto, K., Dismukes, G.C. et al. Inhibition of the catalase reaction of Photosystem II by anions. Photosynth Res 38, 433–440 (1993). https://doi.org/10.1007/BF00046771
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00046771