Mehler Reaction: Friend or Foe in Photosynthesis?

Polle, Andrea

doi:10.1111/j.1438-8677.1996.tb00546.x

Cited by 98 publications

(48 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Takahashi et al (1988) showed that in PSII, in the places of plastoquinone Q A and Q B activity, electron leak may occur, accompanied by a reduction of molecular oxygen to superoxide radical, further dismutated to H 2 O 2 . Another possible source of ROS generation during R1 could be PSI, where overloading of the electron transport chain (ETC) could cause a redirection of some electrons from ferredoxin to O 2 and reducing it via Mehler reaction to superoxide radical, which was then spontaneously dismutated to H 2 O 2 by Cu/Zn-SOD (Polle 1996;Edreva 2005). However, Wiese et al (1998) showed that oxygen reduction in the Mehler reaction was insufficient to protect photosystem I and II against photoinactivation.…”

Section: (D)mentioning

confidence: 99%

Rapid plant rehydration initiates permanent and adverse changes in the photosynthetic apparatus of triticale

Hura

Ostrowska

et al. 2015

Plant Soil

View full text Add to dashboard Cite

Background and aims The reasons for partial recovery after a soil drought are not fully understood and have not been studied so far. This study investigated the physiological and biochemical responses of triticale cultivars with differential recovery ability after soil water deficit. Methods Activity of the photosynthetic apparatus under soil drought followed by rehydration was estimated. Plant antioxidant potential was determined based on the measurement of catalase and peroxidase activity. The levels of hydrogen peroxide and superoxide radical were assessed. Results Under rehydration, the not fully-recovered cultivar experienced further significant increase in the content of H 2 O 2 and inhibited activity of the photosynthetic apparatus, as compared to the drought period. On 42 nd day of the rehydration, the not fully-recovered cultivar showed also a reduced photosynthetic activity in the flag leaves, which resulted in a significant decrease in its grain yield. The first week of a rapid rehydration involved a decrease in total peroxidase and catalase activities. The increased content of H 2 O 2 was compensated only when leaf water content was gradually restored in the first week of the rehydration and no further decrease in the activity of the photosynthetic apparatus was noticed. Conclusions A destructive effect of the rapid rehydration was manifested in an intensification of the physiological processes associated with reactive oxygen species (ROS) overproduction. An important cause of hydrogen peroxide overproduction seems to be the electron leakage due to overloading of the electron transport chain (ETC) in the PSI and PSII.

show abstract

Section: (D)mentioning

confidence: 99%

Rapid plant rehydration initiates permanent and adverse changes in the photosynthetic apparatus of triticale

Hura

Ostrowska

et al. 2015

Plant Soil

View full text Add to dashboard Cite

show abstract

“…It is estimated that under nonstressed conditions up to 20-25% of total non-cyclic photosynthetic electron transport is consumed by the Mehler reaction at light saturation (Robinson, 1988 ;Osmond & Grace, 1995 ;Lovelock & Winter, 1996). Production of O # d − during photosynthetic electron transport can be intensified when plants are exposed to high light intensity combined with an environmental stress factor that restricts photosynthetic CO # fixation, such as chilling, drought stress and mineral nutrient deficiencies (Asada et al, 1977 ;Elstner et al, 1988 ;Cakmak & Marschner, 1992 ;Osmond & Grace, 1995 ;Biehler & Fock, 1996 ;Polle, 1996 ;Fryer et al, 1998 ;Heiser et al, 1998 ;Cakmak & Engels, 1999). Such conditions lead to limited NADP + availability for acceptance of electrons from photosystem I, thus intensifying electron flow to O # from ferrodoxin with a concomitant photooxidative damage to thylakoid constituents by ROS.…”

Section: Zinc Deficiency-enhanced Photooxidationmentioning

confidence: 99%

“…The superoxide radical and its derivates are unavoidable products of normal cell metabolism, and their generation is particularly high during electron transport in chloroplasts and mitochondria (Cakmak et al, 1993 ;Elstner & Osswald, 1994 ;Polle, 1996 ;Alscher et al, 1997). To minimize the destructive effects of ROS, plant cells are equipped with various antioxidants and antioxidative defence enzymes such as superoxide dismutases (SODs), ascorbate peroxidases, ascorbic acid, α-tocopherol and carotenoids (Asada, 1994 ;Cakmak, 1994 ;Foyer et al, 1994 (Fridovich, 1986 ;Bowler et al, 1994).…”

Section: Superoxide Dismutasesmentioning

confidence: 99%

Tansley Review No. 111

2000

View full text Add to dashboard Cite

Zinc deficiency is one of the most widespread micronutrient deficiencies in plants and causes severe reductions in crop production. There are a number of physiological impairments in Zn-deficient cells causing inhibition of the growth, differentiation and development of plants. Increasing evidence indicates that oxidative damage to critical cell compounds resulting from attack by reactive O # species (ROS) is the basis of disturbances in plant growth caused by Zn deficiency. Zinc interferes with membrane-bound NADPH oxidase producing ROS. In Zn-deficient plants the iron concentration increases, which potentiates the production of free radicals. The Zn nutritional status of plants influences photooxidative damage to chloroplasts, catalysed by ROS. Zinc-deficient leaves are highly light-sensitive, rapidly becoming chlorotic and necrotic when exposed to high light intensity. Zinc plays critical roles in the defence system of cells against ROS, and thus represents an excellent protective agent against the oxidation of several vital cell components such as membrane lipids and proteins, chlorophyll, SH-containing enzymes and DNA. The cysteine, histidine and glutamate or aspartate residues represent the most critical Znbinding sites in enzymes, DNA-binding proteins (Zn-finger proteins) and membrane proteins. In addition, animal studies have shown that Zn is involved in inhibition of apoptosis (programmed cell death) which is preceded by DNA and membrane damage through reactions with ROS.

show abstract

“…The tripeptide glutathione (GSH) detoxifies reactive oxygen species directly and is also involved in the regeneration of the radical scavenger ascorbate in the ascorbate-GSH cycle (Polle 1996). The function of GSH is due to the reversible oxidation of the SH group of the amino acid cysteine.…”

Section: Tolerance To Abiotic Stressmentioning

confidence: 99%

“…The formation of superoxide (O2 .-), hydroxyl radicals (OH .-) and singlet oxygen ( 1 O2) during aerobic metabolism is caused by electrons which leak from electron transport chains in chloroplasts and mitochondria. This process is aggravated by many stress forms and induces a radical-scavenging, antioxidative system (Polle 1996, Polle et al 2000, Polle and Schützendübel 2003, Gratao et al 2005.…”

Section: Tolerance To Abiotic Stressmentioning

confidence: 99%

Wood production, wood technology, and biotechnological impacts

Kües¹

2007

View full text Add to dashboard Cite

Mehler Reaction: Friend or Foe in Photosynthesis?

Cited by 98 publications

References 58 publications

Rapid plant rehydration initiates permanent and adverse changes in the photosynthetic apparatus of triticale

Rapid plant rehydration initiates permanent and adverse changes in the photosynthetic apparatus of triticale

Tansley Review No. 111

Wood production, wood technology, and biotechnological impacts

Contact Info

Product

Resources

About