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Antal T, Konyukhov I, Volgusheva A, Plyusnina T, Khruschev S, Kukarskikh G, Goryachev S, Rubin A. Chlorophyll fluorescence induction and relaxation system for the continuous monitoring of photosynthetic capacity in photobioreactors. Physiol Plant 2019; 165:476-486. [PMID: 29345315 DOI: 10.1111/ppl.12693] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 01/08/2018] [Accepted: 01/10/2018] [Indexed: 06/07/2023]
Abstract
The development of high-performance photobioreactors equipped with automatic systems for non-invasive real-time monitoring of cultivation conditions and photosynthetic parameters is a challenge in algae biotechnology. Therefore, we developed a chlorophyll (Chl) fluorescence measuring system for the online recording of the light-induced fluorescence rise and the dark relaxation of the flash-induced fluorescence yield (Qa- - re-oxidation kinetics) in photobioreactors. This system provides automatic measurements in a broad range of Chl concentrations at high frequency of gas-tight sampling, and advanced data analysis. The performance of this new technique was tested on the green microalgae Chlamydomonas reinhardtii subjected to a sulfur deficiency stress and to long-term dark anaerobic conditions. More than thousand fluorescence kinetic curves were recorded and analyzed during aerobic and anaerobic stages of incubation. Lifetime and amplitude values of kinetic components were determined, and their dynamics plotted on heatmaps. Out of these data, stress-sensitive kinetic parameters were specified. This implemented apparatus can therefore be useful for the continuous real-time monitoring of algal photosynthesis in photobioreactors.
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Affiliation(s)
- Taras Antal
- Faculty of Biology, Department of Biophysics, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Ivan Konyukhov
- Faculty of Biology, Department of Biophysics, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Alena Volgusheva
- Faculty of Biology, Department of Biophysics, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Tatyana Plyusnina
- Faculty of Biology, Department of Biophysics, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Sergei Khruschev
- Faculty of Biology, Department of Biophysics, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Galina Kukarskikh
- Faculty of Biology, Department of Biophysics, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Sergey Goryachev
- Faculty of Biology, Department of Biophysics, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Andrey Rubin
- Faculty of Biology, Department of Biophysics, Lomonosov Moscow State University, Moscow 119991, Russia
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Kosourov S, Murukesan G, Seibert M, Allahverdiyeva Y. Evaluation of light energy to H 2 energy conversion efficiency in thin films of cyanobacteria and green alga under photoautotrophic conditions. ALGAL RES 2017; 28:253-63. [DOI: 10.1016/j.algal.2017.09.027] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Scoma A, Hemschemeier A. The hydrogen metabolism of sulfur deprived Chlamydomonas reinhardtii cells involves hydrogen uptake activities. ALGAL RES 2017. [DOI: 10.1016/j.algal.2017.08.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Guo Z, Li Y, Guo H. Effect of Light/Dark Regimens on Hydrogen Production by Tetraselmis subcordiformis Coupled with an Alkaline Fuel Cell System. Appl Biochem Biotechnol 2017; 183:1295-1303. [PMID: 28493138 DOI: 10.1007/s12010-017-2498-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 04/26/2017] [Indexed: 10/19/2022]
Abstract
To improve the photoproduction of hydrogen (H2) by a green algae-based system, the effect of light/dark regimens on H2 photoproduction regulated by carbonyl cyanide m-chlorophenylhydrazone (CCCP) was investigated. A fuel cell was integrated into a photobioreactor to allow online monitoring of the H2 evolution rate and decrease potential H2 feedback inhibition by consuming the generated H2 in situ. During the first 15 h of H2 evolution, the system was subjected to dark treatment after initial light illumination (L/D = 6/9 h, 9/6 h, and 12/3 h). After the dark period, all systems were again exposed to light illumination until H2 evolution stopped. Two peaks were observed in the H2 evolution rate under all three light/dark regimens. Additionally, a high H2 yield of 126 ± 10 mL L-1 was achieved using a light/dark regimen of L 9 h/D 6 h/L until H2 production ceased, which was 1.6 times higher than that obtained under continuous illumination. H2 production was accompanied by some physiological and morphological changes in the cells. The results indicated that light/dark regimens improved the duration and yield of H2 photoproduction by the CCCP-regulated process of Tetraselmis subcordiformis.
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Affiliation(s)
- Zhen Guo
- College of Environmental and Chemical Engineering, Dalian Jiaotong University, Dalian, 116028, China. .,Marine Bioproducts Engineering Group, Dalian Institute of Chemical and Physics, Chinese Academy of Sciences, Dalian, 116023, China.
| | - Ying Li
- College of Environmental and Chemical Engineering, Dalian Jiaotong University, Dalian, 116028, China
| | - Haiyan Guo
- College of Environmental and Chemical Engineering, Dalian Jiaotong University, Dalian, 116028, China
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Scoma A, Tóth SZ. On the pathways feeding the H 2 production process in nutrient-replete, hypoxic conditions. Commentary on the article "Low oxygen levels contribute to improve photohydrogen production in mixotrophic non-stressed Chlamydomonas cultures", by Jurado-Oller et al., Biotechnology for Biofuels, published September 7, 2015; 8:149. Biotechnol Biofuels 2017; 10:116. [PMID: 28484516 PMCID: PMC5418857 DOI: 10.1186/s13068-017-0800-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 04/22/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND Under low O2 concentration (hypoxia) and low light, Chlamydomonas cells can produce H2 gas in nutrient-replete conditions. This process is hindered by the presence of O2, which inactivates the [FeFe]-hydrogenase enzyme responsible for H2 gas production shifting algal cultures back to normal growth. The main pathways accounting for H2 production in hypoxia are not entirely understood, as much as culture conditions setting the optimal redox state in the chloroplast supporting long-lasting H2 production. The reducing power for H2 production can be provided by photosystem II (PSII) and photofermentative processes during which proteins are degraded via yet unknown pathways. In hetero- or mixotrophic conditions, acetate respiration was proposed to indirectly contribute to H2 evolution, although this pathway has not been described in detail. MAIN BODY Recently, Jurado-Oller et al. (Biotechnol Biofuels 8: 149, 7) proposed that acetate respiration may substantially support H2 production in nutrient-replete hypoxic conditions. Addition of low amounts of O2 enhanced acetate respiration rate, particularly in the light, resulting in improved H2 production. The authors surmised that acetate oxidation through the glyoxylate pathway generates intermediates such as succinate and malate, which would be in turn oxidized in the chloroplast generating FADH2 and NADH. The latter would enter a PSII-independent pathway at the level of the plastoquinone pool, consistent with the light dependence of H2 production. The authors concluded that the water-splitting activity of PSII has a minor role in H2 evolution in nutrient-replete, mixotrophic cultures under hypoxia. However, their results with the PSII inhibitor DCMU also reveal that O2 or acetate additions promoted acetate respiration over the usually dominant PSII-dependent pathway. The more oxidized state experienced by these cultures in combination with the relatively short experimental time prevented acclimation to hypoxia, thus precluding the PSII-dependent pathway from contributing to H2 production. CONCLUSIONS In Chlamydomonas, continuous H2 gas evolution is expected once low O2 partial pressure and optimal reducing conditions are set. Under nutrient-replete conditions, the electrogenic processes involved in H2 photoproduction may rely on various electron transport pathways. Understanding how physiological conditions select for specific metabolic routes is key to achieve economic viability of this renewable energy source.
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Affiliation(s)
- Alberto Scoma
- Center for Microbial Ecology and Technology (CMET), Faculty of Bioengineering, University of Gent, Coupure Links 653, 9000 Ghent, Belgium
- Center for Geomicrobiology, Aarhus University, Ny Munkegade 116, 8000 Aarhus, Denmark
| | - Szilvia Z. Tóth
- Biological Research Centre Szeged, Hungarian Academy of Sciences, Temesvári krt. 62, Szeged, 6726 Hungary
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Guo Z, Li Y, Guo H. Characterization of H2 photoproduction by marine green alga Tetraselmis subcordiformis integrated with an alkaline fuel cell. Biotechnol Lett 2016; 38:435-40. [PMID: 26621378 DOI: 10.1007/s10529-015-2008-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2015] [Accepted: 11/24/2015] [Indexed: 10/22/2022]
Abstract
OBJECTIVES To investigate the feasibility of coupling carbonyl cyanide m-chlorophenylhydrazone-regulated photohydrogen production by Tetraselmis subcordiformis in a photobioreactor to an alkaline fuel cell (AFC). RESULTS H2 evolution kinetics in the AFC integrated process was characterized. The duration of H2 evolution was prolonged and its yield was improved about 1.5-fold (to 78 ± 5 ml l(-1)) compared with that of the process without AFC. Improved H2 yield was possibly caused by removal of H2 feedback inhibition by H2 consumption in situ. Decreases in the H2 production rate correlated with the gradual deactivation of PSII and hydrogenase activities. The H2 yield was closely associated with catabolism of starch and protein. CONCLUSION A marine green algal CO2-supplemented culture integrated with in situ H2-consumption by an AFC system was developed as a viable protocol for the H2 production.
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Kodru S, Malavath T, Devadasu E, Nellaepalli S, Stirbet A, Subramanyam R. The slow S to M rise of chlorophyll a fluorescence reflects transition from state 2 to state 1 in the green alga Chlamydomonas reinhardtii. Photosynth Res 2015; 125:219-31. [PMID: 25663564 DOI: 10.1007/s11120-015-0084-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2014] [Accepted: 01/08/2015] [Indexed: 05/03/2023]
Abstract
The green alga Chlamydomonas (C.) reinhardtii is a model organism for photosynthesis research. State transitions regulate redistribution of excitation energy between photosystem I (PS I) and photosystem II (PS II) to provide balanced photosynthesis. Chlorophyll (Chl) a fluorescence induction (the so-called OJIPSMT transient) is a signature of several photosynthetic reactions. Here, we show that the slow (seconds to minutes) S to M fluorescence rise is reduced or absent in the stt7 mutant (which is locked in state 1) in C. reinhardtii. This suggests that the SM rise in wild type C. reinhardtii may be due to state 2 (low fluorescence state; larger antenna in PS I) to state 1 (high fluorescence state; larger antenna in PS II) transition, and thus, it can be used as an efficient and quick method to monitor state transitions in algae, as has already been shown in cyanobacteria (Papageorgiou et al. 1999, 2007; Kaňa et al. 2012). We also discuss our results on the effects of (1) 3-(3,4-dichlorophenyl)-1,4-dimethyl urea, an inhibitor of electron transport; (2) n-propyl gallate, an inhibitor of alternative oxidase (AOX) in mitochondria and of plastid terminal oxidase in chloroplasts; (3) salicylhydroxamic acid, an inhibitor of AOX in mitochondria; and (4) carbonyl cyanide p-trifluoromethoxyphenylhydrazone, an uncoupler of phosphorylation, which dissipates proton gradient across membranes. Based on the data presented in this paper, we conclude that the slow PSMT fluorescence transient in C. reinhardtii is due to the superimposition of, at least, two phenomena: qE dependent non-photochemical quenching of the excited state of Chl, and state transitions.
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Affiliation(s)
- Sireesha Kodru
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500 046, India
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Simon DF, Davis TA, Tercier-Waeber ML, England R, Wilkinson KJ. In situ evaluation of cadmium biomarkers in green algae. Environ Pollut 2011; 159:2630-2636. [PMID: 21696872 DOI: 10.1016/j.envpol.2011.05.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Revised: 05/04/2011] [Accepted: 05/29/2011] [Indexed: 05/31/2023]
Abstract
In situ measurements provide data that are the highly representative of the natural environment. In this paper, laboratory-determined biomarkers of Cd stress that were previously identified for the green alga Chlamydomonas reinhardtii, were tested in two French rivers: a contaminated site on the Riou Mort River and an "uncontaminated" reference site on the Lot River. Transcript abundance levels were determined by real time qPCR for biomarkers thought to be Cd sensitive. Transcript levels were significantly higher (>5 fold) for organisms exposed to the contaminated site as compared to those exposed at the uncontaminated site. Biomarker mRNA levels were best correlated to free Cd (Cd(2+)) rather than intracellular Cd, suggesting that they may be useful indicators of in situ stress. The paper shows that biomarker expression levels increased with time, were sensitive to metal levels and metal speciation and were higher in the "contaminated" as opposed to the "reference" site.
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Affiliation(s)
- Dana F Simon
- Department of Chemistry, University of Montreal, PO Box 6128, Succursale Centre-ville, Montréal, Québec H3C 3J7, Canada
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Ran C, Zhang F, Sun H, Zhao B. Effect of culture medium on hydrogen production by sulfur-deprived marine green algae Platymonas subcordiformis. BIOTECHNOL BIOPROC E 2009; 14:835-41. [DOI: 10.1007/s12257-008-0287-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Guo Z, Chen Z, Zhang W, Yu X, Jin M. Improved hydrogen photoproduction regulated by carbonylcyanide m-chlorophenylhrazone from marine green alga Platymonas subcordiformis grown in CO2-supplemented air bubble column bioreactor. Biotechnol Lett 2008; 30:877-83. [PMID: 18196459 DOI: 10.1007/s10529-008-9637-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Revised: 12/19/2007] [Accepted: 12/19/2007] [Indexed: 11/25/2022]
Abstract
To develop an integrated process of CO(2)-fixation and H(2) photoproduction by marine green microalga Platymonas subcordiformis, the impact of algal cells grown in CO(2)-supplemented air bubble column bioreactor was investigated on H(2) photoproduction regulated by carbonylcyanide m-chlorophenylhrazone. Highest cell growth (3.85 x 10(6) cells ml(-1)), starch content (0.25 +/- 0.08 mg per 10(6)cells) and hydrogen production (50 +/- 3 ml l(-1)) were achieved at 3% CO(2)-supplemented culture, which are respectively 1.4, 2.1, 1.5-fold of the air-supplemented culture. Improved H(2) production correlated well with the increase in starch accumulation. In this process, the algal cells have been recycled for stable H(2) production of 40-50 ml l(-1) over five cycles.
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Affiliation(s)
- Zhen Guo
- Marine Bioproducts Engineering Group, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
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Kosourov S, Patrusheva E, Ghirardi ML, Seibert M, Tsygankov A. A comparison of hydrogen photoproduction by sulfur-deprived Chlamydomonas reinhardtii under different growth conditions. J Biotechnol 2007; 128:776-87. [PMID: 17275940 DOI: 10.1016/j.jbiotec.2006.12.025] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2006] [Accepted: 12/15/2006] [Indexed: 11/28/2022]
Abstract
Continuous photoproduction of H(2) by the green alga, Chlamydomonas reinhardtii, is observed after incubating the cultures for about a day in the absence of sulfate and in the presence of acetate. Sulfur deprivation causes the partial and reversible inactivation of photosynthetic O(2) evolution in algae, resulting in the light-induced establishment of anaerobic conditions in sealed photobioreactors, expression of two [FeFe]-hydrogenases in the cells, and H(2) photoproduction for several days. We have previously demonstrated that sulfur-deprived algal cultures can produce H(2) gas in the absence of acetate, when appropriate experimental protocols were used (Tsygankov, A.A., Kosourov, S.N., Tolstygina, I.V., Ghirardi, M.L., Seibert, M., 2006. Hydrogen production by sulfur-deprived Chlamydomonas reinhardtii under photoautotrophic conditions. Int. J. Hydrogen Energy 31, 1574-1584). We now report the use of an automated photobioreactor system to compare the effects of photoautotrophic, photoheterotrophic and photomixotrophic growth conditions on the kinetic parameters associated with the adaptation of the algal cells to sulfur deprivation and H(2) photoproduction. This was done under the experimental conditions outlined in the above reference, including controlled pH. From this comparison we show that both acetate and CO(2) are required for the most rapid inactivation of photosystem II and the highest yield of H(2) gas production. Although, the presence of acetate in the system is not critical for the process, H(2) photoproduction under photoautotrophic conditions can be increased by optimizing the conditions for high starch accumulation. These results suggest ways of engineering algae to improve H(2) production, which in turn may have a positive impact on the economics of applied systems for H(2) production.
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Affiliation(s)
- Sergey Kosourov
- Institute of Basic Biological Problems RAS, Pushchino, Moscow Region 142290, Russia.
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Kosourov S, Makarova V, Fedorov AS, Tsygankov A, Seibert M, Ghirardi ML. The effect of sulfur re-addition on H(2) photoproduction by sulfur-deprived green algae. Photosynth Res 2005; 85:295-305. [PMID: 16170632 DOI: 10.1007/s11120-005-5105-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2005] [Accepted: 04/05/2005] [Indexed: 05/04/2023]
Abstract
Sulfur deprivation of algal cultures selectively and partially inactivates photosystem II (PSII)-catalyzed O(2) evolution, induces anaerobiosis and hydrogenase expression, and results in sustained H(2) photoproduction for several days. We show that re-addition of limiting amounts of sulfate (1-10 microM final concentration) to the cultures during the H(2)-production phase temporarily reactivates PSII photochemical and O(2)-evolution activity and re-establishes higher rates of electron transport through the photosynthetic electron transport chain. The reactivation of PSII occurs by de novo D1 protein synthesis, but does not result in the re-establishment of aerobic conditions in the reactor, detectable by dissolved-O(2) sensors. However, concomitant H(2) photoproduction is inhibited, possibly due to excessive intra-cellular levels of photosynthetically-evolved O(2). The partial recovery of electron transport rates correlates with the re-oxidation of the plastoquinone (PQ) pool, as observed by pulse-amplitude modulated (PAM) and fluorescence-induction measurements. These results show that the presence of a more oxidized PQ pool releases some of the down-regulation of electron transport caused by the anaerobic conditions.
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Affiliation(s)
- Sergey Kosourov
- National Renewable Energy Laboratory, 1617 Cole Blvd., Golden, CO 80401, USA
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Abstract
This article summarizes knowledge on genes and their respective proteins in the field of green algal hydrogen research. Emphasis is placed on recently cloned genes from the unicellular green alga Chlamydomonas reinhardtii, including HydA1 and HydA2, which encode homologous [Fe]-hydrogenases, Tla1, which encodes a chlorophyll antenna size regulatory gene, SulP, which encodes a chloroplast sulfate permease, and Sta7, which encodes an isoamylase. Analysis of the structure and function of these genes and of their respective proteins in C. reinhardtii, and related unicellular green algae, is presented in light of the role they play in the hydrogen metabolism in these organisms. A discussion is offered as to the potential application of these genes in the field of hydrogen photoproduction.
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Affiliation(s)
- Anastasios Melis
- Department of Plant and Microbial Biology, University of California, 111 Koshland Hall, Berkeley, CA, 94720-3102, USA,
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Kosourov S, Seibert M, Ghirardi ML. Effects of extracellular pH on the metabolic pathways in sulfur-deprived, H2-producing Chlamydomonas reinhardtii cultures. Plant Cell Physiol 2003; 44:146-155. [PMID: 12610217 DOI: 10.1093/pcp/pcg020] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Sustained photoproduction of H(2) by the green alga, Chlamydomonas reinhardtii, can be obtained by incubating cells in sulfur-deprived medium [Ghirardi et al. (2000b) Trends Biotechnol. 18: 506; Melis et al. (2000) Plant Physiol. 122: 127]. The current work focuses on (a) the effects of different initial extracellular pHs on the inactivation of photosystem II (PSII) and O(2)-sensitive H(2)-production activity in sulfur-deprived algal cells and (b) the relationships among H(2)-production, photosynthetic, aerobic and anaerobic metabolisms under different pH regimens. The maximum rate and yield of H(2) production occur when the pH at the start of the sulfur deprivation period is 7.7 and decrease when the initial pH is lowered to 6.5 or increased to 8.2. The pH profile of hydrogen photoproduction correlates with that of the residual PSII activity (optimum pH 7.3-7.9), but not with the pH profiles of photosynthetic electron transport through photosystem I or of starch and protein degradation. In vitro hydrogenase activity over this pH range is much higher than the actual in situ rates of H(2) production, indicating that hydrogenase activity per se is not limiting. Starch and protein catabolisms generate formate, acetate and ethanol; contribute some reductant for H(2) photoproduction, as indicated by 3-(3,4-dichlorophenyl)-1,1-dimethylurea and 2,5-dibromo-6-isopropyl-3-methyl-1,4-benzoquinone inhibition results; and are the primary sources of reductant for respiratory processes that remove photosynthetically generated O(2). Carbon balances demonstrate that alternative metabolic pathways predominate at different pHs, and these depend on whether residual photosynthetic activity is present or not.
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Affiliation(s)
- Sergey Kosourov
- National Renewable Energy Laboratory, 1617 Cole Blvd., Golden, CO 80401, U.S.A
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