The Physiology and Functional Genomics of Cyanobacterial Hydrogenases and Approaches Towards Biohydrogen Production

Chapter
Part of the Advances in Photosynthesis and Respiration book series (AIPH, volume 33)

Summary

Three different enzymes, the nitrogenase and two different hydrogenases, an uptake and a bidirectional enzyme, are involved in cyanobacterial hydrogen metabolism. In strains containing nitrogenase, H2 is produced as a byproduct during nitrogen fixation. Many cyanobacterial strains additionally express an uptake hydrogenase that recycles these reducing equivalents. Since not every nitrogen-fixing strain encodes the genes of the uptake hydrogenase, it seems to be dispensable under some environmental conditions. Genome comparisons suggest that the cyanobacterial uptake hydrogenase requires the presence of five additional accessory genes for its maturation.

The primary function of the bidirectional hydrogenase is to increase energetic yield during fermentation and light induced H2 production in transition states, when cells shift from dark anaerobic conditions to those where light is present. Under oxidizing conditions, the bidirectional enzyme can also catalyze hydrogen uptake. Comparative genomics and database searches reveal the specific association of the pyruvate:ferredoxin/flavodoxin oxidoreductase with the bidirectional hydrogenase, indicating a functional association. This chapter summarizes what is known about the physiological function of the hydrogenases, how they are integrated in the overall metabolism, their phylogenetic ancestry, and their distribution in cyanobacterial genomes.

Oxygenic phototrophs provide the framework that is needed for biological hydrogen production from sunlight and water, and they could be used as a blueprint for biomimetic systems for hydrogen generation. The genetic modifications that have been made to achieve higher production rates are described and future strategies for the use of cyanobacteria as rewarding H2 producers are outlined.

Keywords

Hydrogen Production Cyanobacterial Strain Anabaena Variabilis Uptake Hydrogenase Fermentative Hydrogen Production 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgments

I am especially grateful for the exceptional support I received from Rüdiger Schulz during the major part of my scientific life and I like to thank all the Ph.D. and diploma students I have been working with in the lab and who were part of exciting and many fruitful discussions. My special thanks are to Horst Senger, Reto Strasser, Georg Schmetterer, Eva-Mari Aro, Laurent Cournac, Teruo Ogawa, Aaron Kaplan, Petra Fromme, Anne Jones and Wim Vermaas. Personally I like to thank Kirstin Gutekunst who added a warm and invaluable character to my life.

Financial aid from DFG, COST 841, Innovationsfond des Landes Schleswig-Holstein, Linde AG, Arizona State University and the Intel­lectual Fusion Investment Fund for ASU by Brian and Kelly Swette is gratefully acknowledged.

References

  1. Abdel-Basset R and Bader KP (1997) Characterization of hydrogen photoevolution in Oscillatoria chalybea detected by means of mass spectrometry. Z. Naturforsch C 52: 775–781Google Scholar
  2. Abdel-Basset R and Bader KP (1998) Physiological analyses of the hydrogen gas exchange in cyanobacteria. J Photochem Photobiol B 43: 146–151Google Scholar
  3. Abdel-Basset R, Spiegel S and Bader KP (1998) Saturation of cyanobacterial photoevolution of molecular hydrogen by photosynthetic redox components. J Photochem Photobiol B 47: 31–38Google Scholar
  4. Adams MWW, Mortenson LE and Chen JS (1980) Hydrogenase. Biochim Biophys Acta 594: 105–176.PubMedGoogle Scholar
  5. Adams MWW (1990) The structure and mechanism of iron-hydrogenases. Biochim Biophys Acta 1020: 115–145PubMedGoogle Scholar
  6. Agervald A, Stensjö K, Holmqvist M and Lindblad P (2008) Transcription of the extended hyp-operon in Nostoc sp. strain PCC 7120. BMC Microbiol 8: 69Google Scholar
  7. Almon H and Böger P (1988) Hydrogen metabolism of the unicellular cyanobacterium Chroococcidiopsis thermalis ATCC 29380. FEMS Microbiol Lett. 49: 445–449Google Scholar
  8. Alonso-Lomillo MA, Rudiger O, Maroto-Valiente A, Velez M, Rodriguez-Ramos I, Munoz FJ, Fernandez VM and De Lacey AL (2007) Hydrogenase-coated carbon nanotubes for efficient H2 oxidation. Nano Lett 7: 1603–1608PubMedGoogle Scholar
  9. Ananyev G, Carrieri D and Dismukes GC (2008) Optimization of metabolic capacity and flux through environmental cues to maximize hydrogen production by the cyanobacterium Arthrospira (Spirulina) maxima. Appl Environ Microbiol 74: 6102–6113PubMedGoogle Scholar
  10. Appel J and Schulz R (1996) Sequence analysis of an operon of a NAD(P)-reducing nickel hydrogenase from the cyanobacterium Synechocystis sp. PCC 6803 gives additional evidence for direct coupling of the enzyme to NAD(P)H-dehydrogenase (complex I). Biochim Biophys Acta 1298: 141–147PubMedGoogle Scholar
  11. Appel J, Phunpruch S, Steinmüller K and Schulz, R (2000) The bidirectional hydrogenase of Synechocystis sp. PCC 6803 works as an electron valve during photosynthesis. Arch Microbiol 173: 333–338PubMedGoogle Scholar
  12. Asada K (1999) The water-water cycle in chloroplasts: Scavenging of active oxygens and dissipation of excess photons. Annu Rev Plant Physiol Plant Mol Biol 50: 601–639PubMedGoogle Scholar
  13. Arieli B, Shahak Y, Taglicht D, Hauska G and Padan E (1994) Purification and characterization of sulfide-quinone reductase, a novel enzyme driving anoxygenic photosynthesis in Oscillatoria limnetica. J Biol Chem 269: 5705–5711PubMedGoogle Scholar
  14. Badger MR, von Caemmerer S, Ruuska S and Nakano H (2000) Electron flow to oxygen in higher plants and algae: rates and control of direct photoreduction (Mehler reaction) and RubisCO oxygenase. Philos Trans R Soc Lond B Biol Sci 355: 1433–1446PubMedGoogle Scholar
  15. Battchikova N and Aro EM (2007) Cyanobacterial NDH-1 complexes: multiplicity in function and subunit composition. Physiol Plant 131: 22–32PubMedGoogle Scholar
  16. Barz M, Beimgraben C, Staller T, Germer F, Opitz F, Marquardt C, Schwarz C, Gutekunst K, Vanselow KH, Schmitz R, LaRoche J, Schulz R and Appel J (2010) Distribution analysis of hydrogenases in surface waters of marine and freshwater environments. PLoS One 5: e13846Google Scholar
  17. Bauer CC, Scappino L and Haselkorn R (1993) Growth of the cyanobacterium Anabaena on molecular nitrogen: NifJ is required when iron is limited. Proc Natl Acad Sci USA 90: 8812–8816Google Scholar
  18. Belkin S and Padan E (1978a) Hydrogen metabolism in the facultative anoxygenic cyanobacteria (blue-green algae) Oscillatoria limnetica and Aphanothece halophytica. Arch Microbiol 116: 109–111PubMedGoogle Scholar
  19. Belkin S and Padan E (1978b) Sulfide-dependent hydrogen evolution in the cyanobacterium Oscillatoria limnetica. FEBS Lett 94: 291–294Google Scholar
  20. Benemann JR and Weare NM (1974) Hydrogen Evolution by nitrogen-fixing Anabaena cylindrica cultures. Science 184: 174–175PubMedGoogle Scholar
  21. Benemann JR (2000) Hydrogen production by microalgae. J Appl Phycol 12: 291–300Google Scholar
  22. Bernhard M, Benelli B, Hochkoeppler A, Zannoni D and Friedrich B (1997) Functional and structural role of the cytochrome b subunit of the membrane-bound hydrogenase complex of Alcaligenes eutrophus H16. Eur J Biochem 248: 179–186PubMedGoogle Scholar
  23. Böck A, King PW, Bloeksch M and Posewitz MC (2006) Maturation of hydrogenases. Adv Microb Physiol 51: 1–71PubMedGoogle Scholar
  24. Boison, G; Bothe, H; Hansel, A and Lindblad P (1999) Evidence against a common use of the diaphorase subunits by the bidirectional hydrogenase and by the respiratory complex I in cyanobacteria. FEMS Microbiol Lett 174: 159–165Google Scholar
  25. Boison G, Bothe H and Schmitz O (2000) Transcriptional analysis of hydrogenase genes in the Cyanobacteria Anacystis nidulans and Anabaena variabilis monitored by RT-PCR. Curr Microbiol 40: 315–321PubMedGoogle Scholar
  26. Buchanan BB and Balmer Y (2005) Redox regulation: A broadening horizon. Annu Rev Plant Biol 56: 187–220PubMedGoogle Scholar
  27. Burgdorf T, Lenz O, Buhrke T, van der Linden E, Jones AK, Albracht SP and Friedrich B (2005a) [NiFe]-hydrogenases of Ralstonia eutropha H16: modular enzymes for oxygen-tolerant biological hydrogen oxidation. J Mol Microbiol Biotechnol 10: 181–196PubMedGoogle Scholar
  28. Burgdorf T, van der Linden E, Bernhard M, Yin QY, Back JW, Hartog AF, Muijsers AO, de Koster CG, Albracht SP and Friedrich B (2005b) The soluble NAD+−Reducing [NiFe]-hydrogenase from Ralstonia eutropha H16 consists of six subunits and can be specifically activated by NADPH. J Bacteriol 187: 3122–3132PubMedGoogle Scholar
  29. Burgess BK and Lowe DJ (1996) Mechanism of molybdenum nitrogenase. Chem Rev 96: 2983–3012PubMedGoogle Scholar
  30. Butala M, Zgur-Bertok D and Busby SJ (2009) The bacterial LexA transcriptional repressor. Cell Mol Life Sci 66: 82–93PubMedGoogle Scholar
  31. Carrasco CD, Buettner JA and Golden JW (1995) Programmed DNA rearrangement of a cyanobacterial hupL gene in heterocysts. Proc Natl Acad Sci USA 92: 791–795PubMedGoogle Scholar
  32. Carrasco CD, Holliday SD, Hansel A, Lindblad P and Golden JW (2005) Heterocyst-specific excision of the Anabaena sp. strain PCC 7120 hupL element requires xisC. J Bacteriol 187: 6031–6038PubMedGoogle Scholar
  33. Ciccarelli FD, Doerks T, von Mering C, Creevey CJ, Snel B and Bork P (2006) Toward automatic reconstruction of a highly resolved tree of life. Science 311: 1283–1287PubMedGoogle Scholar
  34. Cooley JW and Vermaas WFJ (2001) Succinate dehydrogenase and other respiratory pathways in thylakoid membranes of Synechocystis sp. strain PCC 6803: Capacity comparisons and physiological function. J Bacteriol 183: 4251–4258PubMedGoogle Scholar
  35. Cournac, L; Mus, F; Bernard, L, Guedeney G, Vignais P and Peltier G (2002) Limiting steps of hydrogen production in Chlamydomonas reinhardtii and Synechocystis PCC 6803 as analysed by light-induced gas exchange transients. Int J Hydr Energ 27: 1229–1237Google Scholar
  36. Cournac L, Guedeney G, Peltier G and Vignais PM (2004) Sustained photoevolution of molecular hydrogen in a mutant of Synechocystis sp. strain PCC 6803 deficient in the type I NADPH-dehydrogenase complex. J Bacteriol 186: 1737–1746PubMedGoogle Scholar
  37. Cracknell JA, Vincent KA, Ludwig M, Lenz O, Friedrich B and Armstrong FA (2008) Enzymatic oxidation of H2 in atmospheric O2: the electrochemistry of energy generation from trace H2 by aerobic microorganisms. J Am Chem Soc 130: 424–425PubMedGoogle Scholar
  38. Dai S, Schwendtmayer C, Schürmann P, Ramaswamy S and Eklund H (1996) Redox signaling in chloroplasts: cleavage of disulfides by an iron-sulfur cluster. Science 287: 655–658Google Scholar
  39. Dietrich LE, Tice MM and Newman DK (2006) The co-evolution of life and Earth. Curr Biol 16: R395–400PubMedGoogle Scholar
  40. Domain F, Houot L, Chauvat F and Cassier-Chauvat C (2004) Function and regulation of the cyanobacterial genes lexA, recA and ruvB: LexA is critical to the survival of cells facing inorganic carbon starvation. Mol Microbiol 53: 65–80PubMedGoogle Scholar
  41. Dross F, Geisler V, Lenger R, Theis F, Krafft T, Fahrenholz F, Kojro E, Duchêne A, Tripier D, Juvenal K and Kröger A (1992) The quinone-reactive Ni/Fe-hydrogenase of Wolinella succinogenes. Eur J Biochem 206: 93–102PubMedGoogle Scholar
  42. Eady RR (1996) Structure-function relationships of alternative nitrogenases. Chem Rev 96: 3013–3030PubMedGoogle Scholar
  43. Epping EHG, Khalili A and Thar R (1999) Photosynthesis and the dynamics of oxygen consumption in a microbial mat as calculated from transient oxygen microprofiles. Limnol Ocean 44: 1936–1948Google Scholar
  44. Fernandez VM, Aguirre R and Hatchikian EC (1984) Reductive activation and redox properties of hydrogenase from Desulfovibrio gigas. Biochim Biophys Acta 790: 1–-7Google Scholar
  45. Ferreira D, Leitão E, Sjöholm J, Oliveira P, Lindblad P, Moradas-Ferreira P and Tamagnini P (2007) Transcription and regulation of the hydrogenase(s) accessory genes, hypFCDEAB, in the cyanobacterium Lyngbya majuscula CCAP 1446/4. Arch Microbiol 188: 609–617PubMedGoogle Scholar
  46. Fromme P, Melkozernov A, Jordan P and Krauss N (2003) Structure and function of photosystem I: interaction with its soluble electron carriers and external antenna systems. FEBS Lett 555: 40–44PubMedGoogle Scholar
  47. Forzi L, Hellwig P, Thauer RK, Sawers RG (2007) The CO and CN- ligands to the active site Fe in [NiFe]-hydrogenase of Escherichia coli have different metabolic origins. FEBS Lett 581: 3317–3321PubMedGoogle Scholar
  48. Frenkel A, Gaffron H and Battley EH (1950) Photosynthesis and photoreduction by the blue green alga, Synechococcus elongatus, Näg. Biol Bull 99: 157–162PubMedGoogle Scholar
  49. Fontecilla-Camps JC, Volbeda A, Cavazza C and Nicolet Y (2007) Structure/function relationships of [NiFe]- and [FeFe]-hydrogenases. Chem Rev 107: 4273–4303PubMedGoogle Scholar
  50. Germer F, Zebger I, Saggu M, Lendzian F, Schulz R and Appel J (2009) Overexpression, isolation and spectroscopic characterization of the bidirectional [NiFe] hydrogenase from Synechocystis sp. PCC 6803. J Biol Chem 284: 36462–36472PubMedGoogle Scholar
  51. Ghirardi ML, Posewitz MC, Maness PC, Dubini A, Yu J and Seibert M (2007) Hydrogenases and hydrogen photoproduction in oxygenic photosynthetic organisms. Annu Rev Plant Biol 58:71–91PubMedGoogle Scholar
  52. Goldet G, Wait AF, Cracknell JA, Vincent KA, Ludwig M, Lenz O, Friedrich B and Armstrong FA (2008) Hydrogen production under aerobic conditions by membrane-bound hydrogenases from Ralstonia species. J Am Chem Soc 130: 11106–11113PubMedGoogle Scholar
  53. Grimme, RA; Lubner, CE; Bryant, DA and Golbeck JH (2008) Photosystem I/molecular wire/metal nanoparticle bioconjugates for the photocatalytic production of H2. J Amer Chem Soc 130: 6308–6309Google Scholar
  54. Gross R, Simon J, Lancaster CR and Kröger A (1998) Identification of histidine residues in Wolinella succinogenes hydrogenase that are essential for menaquinone reduction by H2. Mol Microbiol 30: 639–646PubMedGoogle Scholar
  55. Gross R, Pisa R, Sänger M, Lancaster CR and Simon J (2004) Characterization of the menaquinone reduction site in the diheme cytochrome b membrane anchor of Wolinella succinogenes NiFe-hydrogenase. J Biol Chem 279: 274–281PubMedGoogle Scholar
  56. Guedeney G, Corneille S, Cuiné S and Peltier G (1996) Evidence for an association of ndhB, ndhJ gene products and ferredoxin-NADP-reductase as components of a chloroplastic NAD(P)H dehydrogenase complex. FEBS Lett 378: 277–280PubMedGoogle Scholar
  57. Gupta RS and Griffiths E (2002) Critical issues in bacterial phylogeny. Theor Popul Biol 61: 423–434PubMedGoogle Scholar
  58. Gutekunst K, Phunpruch S, Schwarz C, Schuchardt S, Schulz-Friedrich R and Appel J (2005) LexA regulates the bidirectional hydrogenase in the cyanobacterium Synechocystis sp. PCC 6803 as a transcription activator. Mol Microbiol. 58: 810–823PubMedGoogle Scholar
  59. Gutthann F, Egert M, Marques A and Appel J (2007) Inhibition of respiration and nitrate assimilation enhances photohydrogen evolution under low oxygen concentrations in Synechocystis sp. PCC 6803. Biochim Biophys Acta 1767: 161–169PubMedGoogle Scholar
  60. Hackstein JH, Tjaden J and Huynen M (2006) Mitochondria, hydrogenosomes and mitosomes: products of evolutionary tinkering! Curr Genet 50: 225–245PubMedGoogle Scholar
  61. Hallenbeck PC and Benemann JR (2002) Biological hydrogen production; fundamentals and limiting processes. Int J Hydr Energ 27: 1185–1193Google Scholar
  62. Happe T and Naber JD (1993) Isolation, characterization and N-terminal amino acid sequence of hydrogenase from the green alga Chlamydomonas reinhardtii. Eur J Biochem 214: 475–481PubMedGoogle Scholar
  63. Harbinson J and Hedley CL (1993) Changes in P-700 oxidation during the early stages of the induction of photosynthesis. Plant Physiol 103: 649–660PubMedGoogle Scholar
  64. Helman Y, Tchernov D, Reinhold L, Shibata M, Ogawa T, Schwarz R, Ohad I and Kaplan A (2003) Genes encoding A-type flavoproteins are essential for photoreduction of O2 in cyanobacteria. Curr Biol 13: 230–235PubMedGoogle Scholar
  65. Helman Y, Barkan E, Eisenstadt D, Luz B and Kaplan A (2005) Fractionation of the three stable oxygen isotopes by oxygen-producing and oxygen-consuming reactions in photosynthetic organisms. Plant Physiol 138: 2292–2298PubMedGoogle Scholar
  66. Henderson RA (2005) Mechanistic studies on synthetic Fe-S-based clusters and their relevance to the action of nitrogenases. Chem Rev 105: 2365–2437PubMedGoogle Scholar
  67. Herrero A, Muro-Pastor AM, Valladares A and Flores E (2004) Cellular differentiation and the NtcA transcription factor in filamentous cyanobacteria. FEMS Microbiol Rev 28: 469–487PubMedGoogle Scholar
  68. Herrero A, Muro-Pastor AM, Flores E (2001) Nitrogen control in cyanobacteria. J Bacteriol. 183: 411–425PubMedGoogle Scholar
  69. Hoehler, TM; Alperin, MJ; Albert, DB, Martens CS (1998) Thermodynamic control on hydrogen concentrations in anoxic sediments. Geochim Cosmochim Acta 62: 1745–1756Google Scholar
  70. Hoehler TM, Bebout B and Des Marais DJ (2001) The role of microbial mats in the production of reduced gases on the early Earth. Nature 412: 324–327PubMedGoogle Scholar
  71. Hoffmann D, Gutekunst K, Klissenbauer M, Schulz-Friedrich R and Appel J (2006) Mutagenesis of hydrogenase accessory genes of Synechocystis sp. PCC 6803. Additional homologues of hypA and hypB are not active in hydrogenase maturation. Febs J 273: 4516–4527PubMedGoogle Scholar
  72. Hoover TR, Robertson AD, Cerny RL, Hayes RN, Imperial J, Shah VK and Ludden PW (1987) Identification of the V factor needed for synthesis of the iron-molybdenum cofactor of nitrogenase as homocitrate. Nature 329: 855–857PubMedGoogle Scholar
  73. Houchins JP and Burris RH (1981a) Physiological reactions of the reversible hydrogenase from Anabaena 7120. Plant Physiol 68: 717–721PubMedGoogle Scholar
  74. Houchins JP, Burris RH (1981b) Comparative characte­rization of two distinct hydrogenases from Anabaena sp. strain 7120. J Bacteriol 146: 215–221PubMedGoogle Scholar
  75. Howarth DC and Codd GA (1985) The uptake and production of molecular hydrogen by unicellular cyanobacteria. J Gen Microbiol 131: 1561–1569Google Scholar
  76. Howitt CA and Vermaas WF (1998) Quinol and cytochrome oxidases in the cyanobacterium Synechocystis sp. PCC 6803. Biochemistry 37: 17944–17951PubMedGoogle Scholar
  77. Howitt CA and Vermaas WFJ (1999) The subunits of the NAD(P)-reducing Ni-containing hydrogenase do not act as part of the type-1 NAD(P)H-dehydrogenase in the cyanobacterium Synechocystis sp. PCC 6803. In: Peschek GA, Loffelhardt W, Schmetterer G (eds) Phototrophic Prokaryotes, pp 595–608, Kluwer Academic Publishers, New YorkGoogle Scholar
  78. Ihara M, Nishihara H, Yoon KS, Lenz O, Friedrich B, Nakamoto H, Kojima K, Honma D, Kamachi T and Okura I (2006) Light-driven hydrogen production by a hybrid complex of a [NiFe]-hydrogenase and the cyanobacterial photosystem I. Photochem Photobiol 82: 676–682PubMedGoogle Scholar
  79. Johnson DC, Dean DR, Smith AD and Johnson MK (2005) Structure, function, and formation of biological iron-­sulfur clusters. Annu Rev Biochem 74: 247–281PubMedGoogle Scholar
  80. Jones LW and Bishop NI (1976) Simultaneous Measurement of Oxygen and Hydrogen Exchange from the Blue-Green Alga Anabaena. Plant Physiol 57: 659–665PubMedGoogle Scholar
  81. Jørgensen BB, Revsbech NP, Blackburn TH and Cohen Y (1979) Diurnal Cycle of Oxygen and Sulfide Microgradients and Microbial Photosynthesis in a Cyanobacterial Mat Sediment. Appl Environ Microbiol 38: 46–58PubMedGoogle Scholar
  82. Jørgensen BB, Cohen Y and Revsbech NP (1986) Transition from Anoxygenic to Oxygenic Photosynthesis in a Microcoleus chthonoplastes Cyanobacterial Mat. Appl Environ Microbiol 51: 408–417PubMedGoogle Scholar
  83. Kaneko T, Sato S, Kotani H, Tanaka A, Asamizu E, Nakamura Y, Miyajima N, Hirosawa M, Sugiura M, Sasamoto S, Kimura T, Hosouchi T, Matsuno A, Muraki A, Nakazaki N, Naruo K, Okumura S, Shimpo S, Takeuchi C, Wada T, Watanabe A, Yamada M, Yasuda M and Tabata S (1996) Sequence analysis of the genome of the unicellular cyanobacterium Synechocystis sp. strain PCC6803. II. Sequence determination of the entire genome and assignment of potential protein-coding regions. DNA Res 3: 109–136PubMedGoogle Scholar
  84. King GM (2003) Uptake of carbon monoxide and hydrogen at environmentally relevant concentrations by mycobacteria. Appl Environ Microbiol 69: 7266–7272PubMedGoogle Scholar
  85. King PW, Posewitz MC, Ghirardi ML and Seibert M (2006) Functional studies of [FeFe] hydrogenase maturation in an Escherichia coli biosynthetic system. J Bacteriol 188: 2163–2172PubMedGoogle Scholar
  86. Kiss E, Kós PB and Vass I (2009) Transcriptional regulation of the bidirectional hydrogenase in the cyanobacterium Synechocystis 6803. J Biotechnol 142: 31–37Google Scholar
  87. Korbas M, Vogt S, Meyer-Klaucke W, Bill E, Lyon EJ, Thauer RK and Shima S (2006) The iron-sulfur cluster-free hydrogenase (Hmd) is a metalloenzyme with a novel iron binding motif. J Biol Chem 281: 30804–30813PubMedGoogle Scholar
  88. Kortlüke C and Friedrich B (1992) Maturation of membrane-bound hydrogenase of Alcaligenes eutrophus H16. J Bacteriol 174: 6290–6293PubMedGoogle Scholar
  89. Kuchar J and Hausinger RP (2004) Biosynthesis of metal sites. Chem Rev 104: 509–525PubMedGoogle Scholar
  90. Lambert GR, Daday A and Smith GD (1979) Duration of Hydrogen Formation by Anabaena cylindrica B629 in Atmospheres of Argon, Air, and Nitrogen. Appl Environ Microbiol 38: 530–536PubMedGoogle Scholar
  91. Lambert GR and Smith GD (1980) Hydrogen metabolism by filamentous cyanobacteria. Arch Biochem Biophys 205: 36–50PubMedGoogle Scholar
  92. Leitão E, Oxelfelt F, Oliveira P, Moradas-Ferreira P and Tamagnini P (2005) Analysis of the hupSL operon of the nonheterocystous cyanobacterium Lyngbya majuscula CCAP 1446/4: regulation of transcription and expression under a light-dark regimen. Appl Environ Microbiol 71: 4567–4576PubMedGoogle Scholar
  93. Lenz O, Zebger I, Hamann J, Hildebrandt P and Friedrich B (2007) Carbamoylphosphate serves as the source of CN-, but not of the intrinsic CO in the active site of the regulatory [NiFe]-hydrogenase from Ralstonia eutropha. FEBS Lett 581: 3322–3326PubMedGoogle Scholar
  94. Ley RE, Harris JK, Wilcox J, Spear JR, Miller SR, Bebout BM, Maresca JA, Bryant DA, Sogin ML and Pace NR. (2006) Unexpected diversity and complexity of the Guerrero Negro hypersaline microbial mat. Appl Environ Microbiol 72: 3685–3695PubMedGoogle Scholar
  95. Lieman-Hurwitz J, Haimovich M, Shalev-Malul G, Ishii A, Hihara Y, Gaathon A, Lebendiker M and Kaplan A (2008) A cyanobacterial AbrB-like protein affects the apparent photosynthetic affinity for CO2 by modulating low-CO2-induced gene expression. Environ Microbiol 11: 927–936PubMedGoogle Scholar
  96. Lindblad P and Sellstedt A (1990) Occurrence and localization of an uptake hydrogenase in the filamentous heterocystous cyanobacterium Nostoc PCC 73102. Protoplasma 159: 9–15Google Scholar
  97. Lindblad P, Christensson K, Lindberg P, Fedorov A, Pinto F and Tsygankov A (2002) Photoproduction of H2 by wildtype Anabaena sp. PCC 7120 and a hydrogen uptake deficient mutant: from laboratory experiments to outdoor culture. Int J Hydr Energ 27: 1271–1281Google Scholar
  98. Lissolo, T., S. Pulvin and D. Thomas. (1984) Reactivation of the hydrogenase from Desulfovibrio gigas by hydrogen. Influence of redox potential. J Biol Chem 259: 11725–11729PubMedGoogle Scholar
  99. Long, SP; Zhu, XG; Naidu, SL and Ort DR (2006) Can improvement in photosynthesis increase crop yields? Plant Cell Environ 29: 315–330PubMedGoogle Scholar
  100. Lovley DR, and Goodwin S (1988) Hydrogen concentrations as an indicator of the predominant terminal electronaccepting reactions in aquatic sediments. Geochim Cosmochim Acta 52: 2993–3003Google Scholar
  101. Lubitz W, Reijerse E and van Gastel M (2007) [NiFe] and [FeFe] hydrogenases studied by advanced magnetic resonance techniques. Chem Rev 107: 4331–4365PubMedGoogle Scholar
  102. Lubner CE, Knörzer P, Silva PJ, Vincent KA, Happe T, Bryant DA and Golbeck JH (2010) Wiring an [FeFe]-hydrogenase with photosystem I for light-induced ­hydrogen production. Biochem 49: 10264–10266Google Scholar
  103. Ludwig M, Schulz-Friedrich R and Appel J (2006) Occurrence of hydrogenases in cyanobacteria and anoxygenic photosynthetic bacteria: implications for the phylogenetic origin of cyanobacterial and algal hydrogenases. J Mol Evol 63: 758–768PubMedGoogle Scholar
  104. Ludwig M, Schubert T, Zebger I, Wisitruangsakul N, Saggu M, Strack A, Lenz O, Hildebrandt P and Friedrich B (2009) Concerted action of two novel auxiliary proteins in assembly of the active site in a membrane-bound [NiFe] hydrogenase. J Biol Chem 284: 2159–2168PubMedGoogle Scholar
  105. Ma WM, Deng Y, Ogawa T and Mi HL (2006) Active NDH-1 complexes from the cyanobacterium Synechocystis sp strain PCC 6803. Plant Cell Phys 47: 1432–1436Google Scholar
  106. Maeda S, Badger MR and Price GD (2002) Novel gene products associated with NdhD3/D4-containing NDH-1 complexes are involved in photosynthetic CO2 hydration in the cyanobacterium, Synechococcus sp. PCC7942. Mol Microbiol 43: 425–435PubMedGoogle Scholar
  107. Manyani H, Rey L, Palacios JM, Imperial J and Ruiz-Argüeso T (2005) Gene products of the hupGHIJ operon are involved in maturation of the iron-sulfur subunit of the [NiFe] hydrogenase from Rhizobium leguminosarum bv. viciae. J Bacteriol 187: 7018–7026PubMedGoogle Scholar
  108. Masukawa H, Mochimaru M and Sakurai H (2002) Disruption of the uptake hydrogenase gene, but not of the bidirectional hydrogenase gene, leads to enhanced photobiological hydrogen production by the nitrogen-fixing cyanobacterium Anabaena sp. PCC 7120. Appl Microbiol Biotechnol 58: 618–624PubMedGoogle Scholar
  109. Masukawa H, Inoue K and Sakurai H (2007) Effects of disruption of homocitrate synthase genes on Nostoc sp. strain PCC 7120 photobiological hydrogen production and nitrogenase. Appl Environ Microbiol 73: 7562–7570PubMedGoogle Scholar
  110. McLean PA and Dixon RA (1981) Requirement of nifV gene for production of wild-type nitrogenase enzyme in Klebsiella pneumoniae. Nature 292: 655–656PubMedGoogle Scholar
  111. McTavish H (1998) Hydrogen evolution by direct electron transfer from photosystem I to hydrogenases. J Biochem 123: 644–649PubMedGoogle Scholar
  112. Mehler AH (1951) Studies on reactivities of illuminated chloroplasts. I. Mechanism of the reduction of oxygen and other Hill reagents. Arch Biochem Biophys 33: 65–77PubMedGoogle Scholar
  113. Mehler AH and Brown AH (1952) Studies on reactivities of illuminated chloroplasts. III. Simultaneous photoproduction of and consumption of oxygen studied with oxygen isotopes. Arch Biochem Biophy 38: 365–370Google Scholar
  114. Mentel M and Martin W (2008) Energy metabolism among eukaryotic anaerobes in light of Proterozoic ocean chemistry. Philos Trans R Soc Lond B Biol Sci 363: 2717–2729PubMedGoogle Scholar
  115. Mitsui A and Suda S (1995) Alternative and cyclic appearance of H2 and O2 photoproduction activities under nongrowing conditions in an aerobic nitrogen-fixing unicellular cyanobacterium Synechococcus sp. Curr Microbiol 30: 1–6Google Scholar
  116. Nedergaard J, Golozoubova V, Matthias A, Asadi A, Jacobsson A and Cannon B (2001) UCP1: the only protein able to mediate adaptive non-shivering thermogenesis and metabolic inefficiency. Biochim Biophys Acta 1504: 82–106PubMedGoogle Scholar
  117. Neuer G and Bothe H (1982) The pyruvate: ferredoxin oxidoreductase in heterocysts of the cyanobacterium Anaba­ena cylindrica. Biochim Biophys Acta 716: 358–365PubMedGoogle Scholar
  118. Nicolet Y, de Lacey AL, Vernède X, Fernandez VM, Hatchikian EC and Fontecilla-Camps JC (2001) Crystallographic and FTIR spectroscopic evidence of changes in Fe coordination upon reduction of the active site of the Fe-only hydrogenase from Desulfovibrio desulfuricans. J Am Chem Soc 123: 1596–1601PubMedGoogle Scholar
  119. Oda Y, Samanta SK, Rey FE, Wu L, Liu X, Yan T, Zhou J and Harwood CS (2005) Functional genomic analysis of three nitrogenase isozymes in the photosynthetic bacterium Rhodopseudomonas palustris. J Bacteriol 187: 7784–7794PubMedGoogle Scholar
  120. Oliveira P, Leitão E, Tamagnini P, Moradas-Ferreira P and Oxelfelt F (2004) Characterization and transcriptional analysis of hupSLW in Gloeothece sp. ATCC 27152: an uptake hydrogenase from a unicellular cyanobacterium. Microbiology 150: 3647–3655PubMedGoogle Scholar
  121. Oliveira P and Lindblad P (2008) An AbrB-Like protein regulates the expression of the bidirectional hydrogenase in Synechocystis sp. strain PCC 6803. J Bacteriol 190: 1011–1019PubMedGoogle Scholar
  122. Ogawa T (1991) A gene homologous to the subunit-2 gene of NADH dehydrogenase is essential to inorganic carbon transport of Synechocystis PCC 6803. Proc Natl Acad Sci USA 88: 4275–4279PubMedGoogle Scholar
  123. Ohkawa H, Pakrasi HB and Ogawa T (2000) Two types of functionally distinct NAD(P)H dehydrogenases in Synechocystis sp. strain PCC6803. J Biol Chem 275: 31630–31634PubMedGoogle Scholar
  124. Padan E (1979) Facutative anoxygenic photosynthesis in cyanobacteria. Annu Rev Plant Physiol Plant Mol Biol 30: 27–40Google Scholar
  125. Pandey AS, Harris TV, Giles LJ, Peters JW and Szilagyi RK (2008) Dithiomethylether as a ligand in the hydrogenase h-cluster. J Am Chem Soc 130: 4533–4540PubMedGoogle Scholar
  126. Papen H, Kentemich T, Schmülling T and Bothe H (1986) Hydrogenase activities in cyanobacteria. Biochimie 68: 121–132PubMedGoogle Scholar
  127. Patterson-Fortin LM, Colvin KR and Owttrim GW (2006) A LexA-related protein regulates redox-sensitive expression of the cyanobacterial RNA helicase, crhR. Nucleic Acids Res 34: 3446–3454PubMedGoogle Scholar
  128. Patterson-Fortin LM and Owttrim GW (2008) A Synechocystis LexA-orthologue binds direct repeats in target genes. FEBS Lett 582: 2424–2430PubMedGoogle Scholar
  129. Peters JW and Szilagyi RK (2006) Exploring new frontiers of nitrogenase structure and mechanism. Curr Opin Chem Biol 10: 101–108PubMedGoogle Scholar
  130. Posewitz MC, King PW, Smolinski SL, Zhang L, Seibert M and Ghirardi ML (2004) Discovery of two novel radical S-adenosylmethionine proteins required for the assembly of an active [Fe] hydrogenase. J Biol Chem 279: 25711–25720PubMedGoogle Scholar
  131. Reissmann S, Hochleitner E, Wang H, Paschos A, Lottspeich F, Glass RS and Böck A (2003) Taming of a poison: biosynthesis of the NiFe-hydrogenase cyanide ligands. Science 299 1067–1070PubMedGoogle Scholar
  132. Richmond A (2000) Microalgal biotechnology at the turn of the millenium: a personal view. J Appl Phycol 12: 441–451Google Scholar
  133. Roseboom W, De Lacey AL, Fernandez VM, Hatchikian EC and Albracht SP (2006) The active site of the [FeFe]-hydrogenase from Desulfovibrio desulfuricans. II. Redox properties, light sensitivity and CO-ligand exchange as observed by infrared spectroscopy. J Biol Inorg Chem 11: 102–118PubMedGoogle Scholar
  134. Rousseau F, Sétif P and Lagoutte B (1993) Evidence for the involvement of PSI-E subunit in the reduction of ferredoxin by photosystem I. EMBO J 12: 1755–1765PubMedGoogle Scholar
  135. Schansker G, Srivastava A, Govindjee and Strasser RJ (2003) Characterization of the 820-nm transmission signal paralleling the chlorophyll a fluorescence rise (OJIP) in pea leaves. Funct Plant Biol 30: 785–796Google Scholar
  136. Schansker G, Tóth SZ and Strasser RJ (2005) Methylviologen and dibromothymoquinone treatments of pea leaves reveal the role of photosystem I in the Chl a fluorescence rise OJIP. Biochim Biophys Acta 1706: 250–261PubMedGoogle Scholar
  137. Schansker G, Tóth SZ and Strasser RJ (2006) Dark recovery of the Chl a fluorescence transient (OJIP) after light adaptation: the qT-component of non-photochemical quenching is related to an activated photosystem I acceptor side. Biochim Biophys Acta 1757: 787–797PubMedGoogle Scholar
  138. Schmitz O and Bothe H (1996a) The diaphorase subunit HoxU of the bidirectional hydrogenase as electron transferring protein in cyanobacterial respiration? Naturwissenschaften 83: 525–527PubMedGoogle Scholar
  139. Schmitz O and Bothe H (1996b) NAD(P)+-dependent hydrogenase activity in extracts from the cyanobacterium Anacystis nidulans, FEMS Microbiol Lett 135: 97–101Google Scholar
  140. Schmitz O, Boison G and Bothe H (2001a) Quantitative analysis of expression of two circadian clock-controlled gene clusters coding for the bidirectional hydrogenase in the cyanobacterium Synechococcus sp. PCC7942. Mol Microbiol 41: 1409–1417PubMedGoogle Scholar
  141. Schmitz O, Gurke J and Bothe H (2001b) Molecular evidence for the aerobic expression of nifJ, encoding pyruvate:ferredoxin oxidoreductase, in cyanobacteria. FEMS Microbiol Lett 195: 97–102PubMedGoogle Scholar
  142. Schmitz O, Boison G, Salzmann H, Bothe H, Schütz K, Wang SH and Happe T (2002) HoxE - a subunit specific for the pentameric bidirectional hydrogenase complex (HoxEFUYH) of cyanobacteria. Biochim Biophys Acta 1554: 66–74PubMedGoogle Scholar
  143. Schneider K and Schlegel HG (1977) Localization and stability of hydrogenases from aerobic hydrogen bacteria. Arch Microbiol 112: 229–238PubMedGoogle Scholar
  144. Schrautemeier B and Böhme H (1985) Distinct ferredoxin for nitrogen-fixation isolated from heterocysts of the cyanobacterium Anabaena variabilis. FEBS Lett 184, 304–308Google Scholar
  145. Schubert T, Lenz O, Krause E, Volkmer R and Friedrich B (2007) Chaperones specific for the membrane-bound [NiFe]-hydrogenase interact with the Tat signal peptide of the small subunit precursor in Ralstonia eutropha H16. Mol Microbiol 66: 453–467PubMedGoogle Scholar
  146. Schreiber U, Endo T, Mi HL and Asada K (1995) Quenching analysis of chlorophyll fluorescence by the saturation pulse method – particular aspects relating to the study of eukaryotic algae and cyanobacteria. Plant Cell Physiol 36: 873–882Google Scholar
  147. Schröder O, Bleijlevens B, de Jongh TE, Chen Z, Li T, Fischer J, Förster J, Friedrich CG, Bagley KA, Albracht SP and Lubitz W (2007) Characterization of a cyanobacterial-like uptake [NiFe] hydrogenase: EPR and FTIR spectroscopic studies of the enzyme from Acidithiobacillus ferrooxidans. J Biol Inorg Chem 12: 212–233PubMedGoogle Scholar
  148. Seabra R, Santos A, Pereira S, Moradas-Ferreira P and Tamagnini P (2009) Immunolocalization of the uptake hydrogenase in the marine cyanobacterium Lyngbya majuscula CCAP 1446/4 and two Nostoc strains. FEMS Microbiol Lett 292: 57–62PubMedGoogle Scholar
  149. Serebryakova LT, Zorin NA and Gogotov IN (1992) Hydrogenase activity in filamentous cyanobacteria. Microbiology 61: 107–112Google Scholar
  150. Serebryakova LT, Zorin NA and Lindblad P (1994) Reversible hydrogenase in Anabaena variabilis ATCC 29413 – presence and localization in non-N2 fixing cells. Arch Microbiol 161: 140–144Google Scholar
  151. Serebryakova LT, Medina M, Zorin NA, Gogotov IN, Cammack R (1996) Reversible hydrogenase of Anabaena variabilis ATCC 29413: catalytic properties and characterization of redox centres. FEBS Lett 383: 79–82PubMedGoogle Scholar
  152. Serebryakova LT, Sheremetieva M, Tsygankov AA (1998) Reversible hydrogenase activity of Gloeocapsa alpicola in continuous culture. FEMS Microbiol Lett 166: 89–94Google Scholar
  153. Serebryakova LT and Sheremetieva ME (2006) Characteriza­tion of catalytic properties of hydrogenase isolated from the unicellular cyanobacterium Gloeocapsa alpicola CALU 743. Biochem Moscow 71: 1370–1376Google Scholar
  154. Serebryakova LT and Tsygankov AA (2007) Two-stage ­system for hydrogen production by immobilized cyanobacterium Gloeocapsa alpicola CALU 743. Biotechnol Prog 23: 1106–1110PubMedGoogle Scholar
  155. Shibata M, Ohkawa H, Kaneko T, Fukuzawa H, Tabata S, Kaplan A and Ogawa T (2001) Distinct constitutive and low-CO2-induced CO2 uptake systems in cyanobacteria: genes involved and their phylogenetic relationship with homologous genes in other organisms. Proc Natl Acad Sci USA 98: 11789–11794PubMedGoogle Scholar
  156. Shima S, Pilak O, Vogt S, Schick M, Stagni MS, Meyer-Klaucke W, Warkentin E, Thauer RK and Ermler U (2008) The crystal structure of [Fe]-hydrogenase reveals the geometry of the active site. Science 321: 572–575PubMedGoogle Scholar
  157. Sjöholm J, Oliveira P and Lindblad P (2007) Transcription and regulation of the bidirectional hydrogenase in the cyanobacterium Nostoc sp. strain PCC 7120. Appl Environ Microbiol 73: 5435–5446PubMedGoogle Scholar
  158. Stal LJ and Moezelaar R (1997) Fermentation in cyanobacteria. FEMS Microbiol Rev 21: 179–211Google Scholar
  159. Summerfield TC, Toepel J and Sherman LA (2008) Low-oxygen induction of normally cryptic psbA genes in cyanobacteria. Biochemistry 47: 12939–12941PubMedGoogle Scholar
  160. Tamagnini P, Leitão E, Oliveira P, Ferreira D, Pinto F, Harris DJ, Heidorn T and Lindblad P (2007) Cyanobacterial hydrogenases: diversity, regulation and applications. FEMS Microbiol Rev 31: 692–720PubMedGoogle Scholar
  161. Tel-Or E, Luijk LW and Packer L (1978) Hydrogenase in N2-fixing cyanobacteria. Arch Biochem Biophys 185: 185–194PubMedGoogle Scholar
  162. Thomann H, Bernardo M and Adams MWW (1991) Pulsed ENDOR and ESEEM spectroscopic evidence for unusual nitrogen coordinaton to the novel H2-activating Fe-S center in hydrogenase. J Amer Chem Soc 113: 7044–7046Google Scholar
  163. Tichy M and Vermaas W (1999) In vivo role of catalase-peroxidase in Synechocystis sp. strain PCC 6803. J Bacteriol 181: 1875–1882PubMedGoogle Scholar
  164. Troshina O, Serebryakova L, Sheremetieva M and Lindblad P (2002) Production of H2 by the unicellular cyanobacterium Gloeocapsa alpicola CALU 743 during fermentation. Int J Hydr Energ 27: 1283–1289Google Scholar
  165. Tsygankov AA, Serebryakova LT, Rao KK and Hall DO (1998) Acetylene reduction and hydrogen photoproduction by wild-type and mutant strains of Anabaena at different CO2 and O2 concentrations. FEMS Microbiol Lett 167: 13–17Google Scholar
  166. Tsygankov AA, Borodin VB, Rao KK and Hall DO (1999) H2 Photoproduction by batch culture of Anabaeana variabilis ATCC 29413 and its mutant PK84 in a photobioreactor. Biotech Bioeng 64: 709–715Google Scholar
  167. Tsygankov AA, Fedorov AS, Kosourov SN and Rao KK (2002) Hydrogen production by cyanobacteria in an automated outdoor photobioreactor under aerobic conditions. Biotechnol Bioeng 80: 777–783PubMedGoogle Scholar
  168. van Dam PJ, Reijerse EJ and Hagen WR (1997) Identification of a putative histidine base and of a non-protein nitrogen ligand in the active site of Fe-hydrogenases by one-dimensional and two-dimensional electron spin-echo envelope-modulation spectroscopy. Eur J Biochem 248: 355–361PubMedGoogle Scholar
  169. Van der Oost J and Cox RP (1989) Hydrogenase activity in nitrate-grown cells of the unicellular cyanobacterium Cyanothece PCC 7822. Arch Microbiol 151: 40–43Google Scholar
  170. Van der Oost J, Bulthuis BA, Feitz S, Krab K and Krayenhof R (1989) Fermentation of the unicellular cyanobacterium Cyanothece PCC 7822. Arch Microbiol 152: 415–419Google Scholar
  171. Vignais PM, Dimon B, Zorin NA, Colbeau A and Elsen S (1997) HupUV proteins of Rhodobacter capsulatus can bind H2: evidence from the H-D exchange reaction. J Bacteriol 179: 290–292PubMedGoogle Scholar
  172. Vignais PM, Dimon B, Zorin NA, Tomiyama M and Colbeau A (2000) Characterization of the hydrogen-deuterium exchange activities of the energy-transducing HupSL hydrogenase and H2-signaling HupUV hydrogenase in Rhodobacter capsulatus. J Bacteriol 182: 5997–6004PubMedGoogle Scholar
  173. Vignais PM, Billoud B, Meyer J (2001) Classification and phylogeny of hydrogenases. FEMS Microbiol Rev 25: 455–501PubMedGoogle Scholar
  174. Vignais PM and Billoud B (2007) Occurrence, classification and biological function of hydrogenases: an overview. Chem Rev 107: 4206–4272PubMedGoogle Scholar
  175. Vincent KA, Cracknell JA, Clark JR, Ludwig M, Lenz O, Friedrich B and Armstrong FA (2006) Electricity from low-level H2 in still air–an ultimate test for an oxygen tolerant hydrogenase. Chem Commun (Camb) 28: 5033–5035Google Scholar
  176. Vogt S, Lyon EJ, Shima S and Thauer RK (2007) The exchange activities of [Fe] hydrogenase (iron-sulfur-cluster-free hydrogenase) from methanogenic archaea in comparison with the exchange activities of [FeFe] and [NiFe] hydrogenases. J Biol Inorg Chem 13: 97–106PubMedGoogle Scholar
  177. Westermann P, Jorgensen B, Lange L, Ahring BK and Christensen CH (2007) Maximizing renewable hydrogen production from biomass in a bio/catalytic refinery int. J Hydr Energ 32: 4135–4141Google Scholar
  178. Weyman PD, Pratte B and Thiel T (2008) Transcription of hupSL in Anabaena variabilis ATCC 29413 is regulated by NtcA and not by hydrogen. Appl Environ Microbiol 74: 2103–2110PubMedGoogle Scholar
  179. Wolk CP, Ernst A, Elhai J (1994) Heterocyst metabolism and development. In: Bryant DA (ed) The Molecular Biology of Cyanobacteria, pp 69–823. Kluwer Academic Publishers, DordrechtGoogle Scholar
  180. Woodward J, Orr M, Cordray K and Greenbaum E (2000) Enzymatic production of biohydrogen. Nature 405: 1014–1015PubMedGoogle Scholar
  181. Yoon JH, Shin JH, Kim MS, Sim SJ and Park TH (2006) Evaluation of conversion efficiency of light to hydrogen energy by Anabaena variabilis. Int J Hydr Energ 31: 721–727Google Scholar
  182. Yoshino F, Ikeda H, Masukawa H and Sakurai H (2007) High photobiological hydrogen production activity of a Nostoc sp. PCC 7422 uptake hydrogenase-deficient mutant with high nitrogenase activity. Mar Biotechnol (NY) 9: 101–112Google Scholar
  183. Zhang P, Battchikova N, Jansen T, Appel J, Ogawa T and Aro EM (2004) Expression and functional roles of the two distinct NDH-1 complexes and the carbon acquisition complex NdhD3/NdhF3/CupA/Sll1735 in Synechocystis sp PCC 6803. Plant Cell 16: 3326–3340PubMedGoogle Scholar
  184. Zilberman S, Stiefel EI, Cohen MH and Car R (2006) Resolving the CO/CN ligand arrangement in CO-inactivated [FeFe] hydrogenase by first principles density functional theory calculations. Inorg Chem 45: 5715–5717PubMedGoogle Scholar

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© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  1. 1.Botanisches InstitutChristian-Albrechts-UniversitätKielGermany

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