Effects of small water clusters on the growth and microcystin production of Microcystis aeruginosa

Abstract

Microcystis aeruginosa FACHB 905 was used as a model organism to study the effects of small water clusters (SWCs) on the growth and microcystin (MC) production of toxic cyanobacteria. The results showed that SWCs were able to stimulate the growth of Microcystis aeruginosa, which resulted in increased cell numbers and higher specific growth rates after a 30-d treatment. The cell morphology indicated that Microcystis aeruginosa was in a better state of growth, and it was more prone to divide in SWCs than in normal water clusters. The SWCs treatment up-regulated MC synthesis and exudation in 10 d in Microcystis aeruginosa, and the intra-cellular MC content decreased after the 20th day subsequently. Moreover, the cellular photosynthetic pigment contents were temporarily stimulated by SWCs. A possible reason is that SWCs stimulated the growth by promoting photosynthesis, whereas the increased MC production was relevant to pigment contents.

Keywords

small water clusters (SWCs) / Microcystis aeruginosa / microcystin / secondary metabolism

References

[1] Roy R., Tiller W. A., Bell I., et al. The structure of liquid water; novel insights from materials research; potential relevance to homeopathy[J]. Materials Research Innovations, 2005, 9(4): 577-608.

[2] Levitt M., Park B. H. Water: Now you see it, now you don’t[J]. Structure, 1993, 1(4): 223-226.

[3] Woutersen S., Emmerichs U., Bakker H. J. Femtosecond mid-IR pump-probe spectroscopy of liquid water: Evidence for a two-component structure[J]. Science, 1997, 278(5338): 658-660.

[4] Kusanagi H. 17O-NMR spectra of the isolated water molecules in hydrophobic poly (ɛ-caprolactone)[J]. Polymer Journal, 1996, 28(9): 825-826.

[5] Zhao L., Tan X. Study on hexcirclic structure of water and its effect on thermodenaturation of lysozyme[J]. Journal of Tianjin University, 2000, 33(1): 14-16.

[6] Zhang J. P., Zhao L., Tan X. Structural change of water clusters and the corresponding biological effects[J]. Chemistry, 2004, 67(4): 278-283.

[7] Na P., Chen B., Wang Y., et al. Analysis and simulation of molecular dynamics of lysozyme in water cluster system[J]. Transactions of Tianjin University, 2012, 18(1): 1-7.

[8] Kolb B, Thonhauser T Waals density functional study of energetic, structural, and vibrational properties of small water clusters and ice Ih[J]. Physical Review B, 2011, 84(4): 045116

[9] Rotzinger F. P. Structure of the transition states and intermediates formed in the water-exchange of metal hexaaqua ions of the first transition series[J]. Journal of the American Chemical Society, 1996, 118(28): 6760-6766.

[10] Agre P., Kozono D. Aquaporin water channels: Molecular mechanisms for human diseases[J]. FEBS Letters, 2003, 555(1): 72-78.

[11] Long B. M., Jones G. J., Orr P. T. Cellular microcystin content in N-limited Microcystis aeruginosa can be predicted from growth rate[J]. Applied and Environmental Microbiology, 2001, 67(1): 278-283.

[12] Wu Z. X., Gan N. Q., Song L. R. Genetic diversity: Geographical distribution and toxin profiles of Microcystis strains (Cyanobacteria) in China[J]. Journal of Integrative Plant Biology, 2007, 49(3): 262-269.

[13] Qian H. F., Sheng G. D., Liu W. P., et al. Inhibitory effects of atrazine on Chlorella vulgaris as assessed by real-time polymerase chain reaction[J]. Environmental Toxicology and Chemistry, 2008, 27(1): 182-187.

[14] Stanier R. Y., Kunisawa R., Mandel M., et al. Purification and properties of unicellular blue-green algae (order chroococcales)[J]. Bacteriological Reviews, 1971, 35(2): 171-205.

[15] Wang L S, Wu F, Wang R S. Preparation Method and Device of the Six-Ring Water: CN, 1214322A[P]. 1999-04-21(in Chinese).

[16] Guo J G, Wang J T. Water Treatment Material and Methods for Preparation of Six-Ring Water: CN, 101623602A[P]. 2010-01-13(in Chinese).

[17] Li X. L., Pan H. Y., Xu J., et al. Allelopathic effects of Ceratophyllum demersum and Microcystis aeruginosa in cocultivation[J]. Acta Scientiae Circumstantiae, 2008, 28(11): 2243-2249.

[18] Men Y. J., Hu H. Y. Effects of allelochemical EMA from reed on the production and release of cyanotoxins in Microcystis aeruginosa[J]. Environmental Science, 2007, 28(9): 2058-2062.

[19] Voeste D., Levine L. H., Levine H. G., et al. Pigment composition and concentrations within the plant (Ceratophyllum demersum L.) component of the STS-89 C.E.B.A.S. Mini-Module spaceflight experiment[J]. Advances in Space Research, 2003, 31(1): 211-214.

[20] White S. H., Duivenvoorden L. J., Fabbro L. D. A decisionmaking framework for ecological impacts associated with the accumulation of cyanotoxins (cylindrospermopsin and microcystin)[J]. Lakes and Reserviors: Research and Management, 2005, 10(1): 25-37.

[21] Jang M. H., Ha K., Takamura N. Microcystin production by Microcystis aeruginosa exposed to different stages of herbivorous zooplankton[J]. Toxicon, 2008, 51(5): 882-889.

[22] Dai R. H., Liu H. J., Qu J. H., et al. Relationship of energy charge and toxin content of Microcystis aeruginosa in nitrogen-limited or phosphorous-limited cultures[J]. Toxicon, 2008, 51(4): 649-658.

[23] Gong Y., Song L. R., Wu X. Q., et al. Effects of arsenate on microcystin content and leakage of Microcystis strain PCC7806 under various phosphate regimes[J]. Environmental Toxicology, 2009, 24(1): 87-94.