Inhibitory Effect of $Zn^{+2}$ on Tolaasin-induced Hemolysis

$Zn^{+2}$에 의한 Tolaasin의 용혈활성 저해효과

  • Cho, Kwang-Hyun (Department of Agricultural Chemistry, Chungbuk National University) ;
  • Kim, Sung-Tae (Department of Agricultural Chemistry, Chungbuk National University) ;
  • Kim, Young-Kee (Department of Agricultural Chemistry, Chungbuk National University)
  • 조광현 (충북대학교 농업생명환경대학 농화학과) ;
  • 김성태 (충북대학교 농업생명환경대학 농화학과) ;
  • 김영기 (충북대학교 농업생명환경대학 농화학과)
  • Published : 2006.12.31

Abstract

Tolaasin, a pore-forming toxin, is a 1,985 Da peptide produced by Pseudomonas tolaasii and causes a brown blotch disease on cultivated mushrooms. Tolaasin forms pores on the plasma membrane of various cells including fungi, bacteria, plant as well as erythrocytes, and destroys cell structure. $Zn^{+2}$ has been known to block the tolaasin activity by an unknown mechanism. Thus, we investigated the inhibitory effects of $Zn^{+2}$ on the tolaasin-induced hemolysis to understand the molecular mechanism of tolaasin-induced pore formation. $Zn^{+2}$ and $Cd^{+2}$ inhibited the tolaasin-induced hemolysis in a dose-dependent manner and their Ki values were 170 ${\mu}M$ and 20 mM, respectively. The effect of $Zn^{+2}$ was reversible since the subsequent addition of EDTA chelates $Zn^{+2}$ and removes the inhibitory effect of $Zn^{+2}$. When an osmotic protectant, PEG 2000, was added, the tolaasin-induced hemolysis was not observed. After the removal of osmotic protectant by centrifugation, resuspended erythrocytes with fresh medium were immediately hemolyzed, while the addition of $Zn^{+2}$ prevented from hemolysis, implying that tolaasin-induced pores on the membrane were already formed in the medium containing osmotic protectant. These results suggest that $Zn^{+2}$ inhibits the activity of tolaasin pores and it has minor effects on the membrane binding of tolaasin and the formation of pore.

Tolaasin은 Pseudomonas tolaasii에 의해 생성된 분자량 1,985 Da의 펩티드로서 재배버섯에 갈반병을 유발하는 원인 독소이다. Tolaasin은 곰팡이, 세균, 식물세포 뿐만 아니라 적혈구의 원형질막에 이온통로를 형성하여 세포를 파괴한다. $Zn^{+2}$는 tolaasin의 활성을 저해함이 알려졌으나, 자세한 기작은 밝혀지지 않았다. 따라서, 본 연구에서는 tolaasin의 이온통로 형성에 대한 분자기작을 밝히기 위하여, 적혈구 용혈현상에 대한 $Zn^{+2}$의 저해효과를 조사하였다. $Zn^{+2}$$Cd^{+2}$은 tolaasin의 용혈활성을 농도의존적으로 저해하였으며, Ki 값은 각각 170 ${\mu}M$과 20 mM 이었다. $Zn^{+2}$의 저해효과는 EDTA의 첨가로 제거되어 $Zn^{+2}$의 효과가 가역적임을 보여준다. 한편, tolaasin과 함께 삼투억제제인 PEG 2000을 가하였을 때, 용혈현상은 나타나지 않았다. 적혈구를 원심분리로 회수하고 PEG 2000을 제거한 후, 신선한 반응용액에 현탁하였을 때, 용혈현상은 즉시 관측되었다. 그러나, 이때에도 $Zn^{+2}$가 존재시에는 용혈현상이 억제되었으며, 이것은 삼투억제제의 처리중에 이미 이온통로가 만들어졌음을 의미한다. 이러한 결과는 $Zn^{+2}$가 tolaasin의 세포막 결합 및 이온통로 형성에는 영향이 적으며, 형성된 이온통로의 활성을 저해함을 보인다.

Keywords

References

  1. Tolaas, A. G. (1915) A bacterial disease of cultivated mushrooms. Phytopathol. 5, 51-54
  2. Kim, J. W., Kim, K. H. and Kang, H. J. (1994) Studies on the pathogenic Pseudomonas causing bacterial disease of cultivated mushroom in Korea: 1. on the causal organisms of the rots of Agaricus bisporus, Pleurotus ostreatus, and Lentinus edodes. Kor. J. Plant Pathol. 10, 197-210
  3. Peng, J. T. (1986) Resistance to disease in Agaricus bisporus (lange) imbach. Ph.D. Thesis., Dept. Plant Sci., Univ. Leeds., UK
  4. Nutkins, J. C., Mortishire-Smith, R. J., Packman, L. C., Brodey, C. L., Rainey, P. B., Johnstone, K. and Williams, D. H. (1991) Structure determination of tolaasin, an extracellular lipodepsipeptide produced by the mushroom pathogen Pseudomonas tolaasii Paine. J. Am. Chem. Soc. 113, 2621-2627 https://doi.org/10.1021/ja00007a040
  5. Mortishire-Smith, R. J., Nutkins, J. C., Packman, L. C., Brodey, C. L., Rainey, P. B., Johnstone, K. and Williams, D. H. (1991) Determination of the structure of an extracellular peptide produced by the mushroom saprotroph Pseudomonas reactans. Tetrahedron 47, 3645-3654 https://doi.org/10.1016/S0040-4020(01)80877-2
  6. Shirata, A., Sugaya, K., Takasugi, M. and Monde, K. (1995) Isolation and biological activity of toxins produced by a Japanese strain of Pseudomonas tolaasii, the pathogen of bacterial rot of cultivated oyster mushroom. Ann. Phytopathol. Soc. Jpn. 61, 493-502 https://doi.org/10.3186/jjphytopath.61.493
  7. Bassarello, C., Lazzaroni, S., Bifulco, G., Lo Cantore, P., Iacobellis, N. S., Riccio, R., Gomez-Paloma, L. and Evidente, A. (2004) Tolaasins A-E, five new lipodepsipeptides produced by Pseudomonas tolaasii. J. Nat. Prod. 67, 811-816 https://doi.org/10.1021/np0303557
  8. Mortishire-Smith, R. J., Drake, A. F., Nutkins, J. C. and Williams, D. H. (1991) Left handed ${\alpha}$-helix formation by a bacterial peptide. FEBS Lett. 278, 244-246 https://doi.org/10.1016/0014-5793(91)80126-N
  9. Jourdan, F., Lazzaroni, S., Mendez, B. L., Lo Cantore, P., de Julio, M., Amodeo, P., Iacobellis, N. S., Evidente, A. and Motta, A. (2003) A left-handed alpha-helix containing both Land D-amino acids: the solution structure of the antimicrobial lipodepsipeptide tolaasin. Proteins 52, 534-543 https://doi.org/10.1002/prot.10418
  10. Coraiola, M., Lo Cantore, P., Lazzaroni, S., Evidente, A., Iacobellis, N. S. and Dalla Serra, M. (2006) WLIP and tolaasin I, lipodepsipeptides from Pseudomonas reactans and Pseudomonas tolaasii, permeabilise model membranes. Biochim. Biophys. Acta 1758, 1713-1722 https://doi.org/10.1016/j.bbamem.2006.06.023
  11. Brodey, C. L., Rainey, P. B., Tester, M. and Johnstone, K. (1991) Bacterial blotch disease of the cultivated mushroom is caused by an ion channel forming lipodepsipeptide toxin. Mol. Plant-Microbe Interact. 4, 407-411 https://doi.org/10.1094/MPMI-4-407
  12. Rainey, P. B., Brodey, C. L. and Johnstone, K. (1991) Biological properties and spectrum of activity of tolaasin, a lipodepsipeptide toxin produced by the mushroom pathogen Pseudomonas tolaasii. Physiol. Mol. Plant Pathol. 39, 57-70 https://doi.org/10.1016/0885-5765(91)90031-C
  13. Cho, K. H., Park, K. S. and Kim, Y. K. (2000) Hemolytic properties of tolaasin causing the brown blotch disease on oyster mushroom. J. Kor. Soc. Agricul. Chem. Biotechnol. 43, 190-195
  14. Cho, K. H. and Kim, Y. K. (2003) Two types of ion channel formation of tolaasin, a Pseudomonas peptide toxin. FEMS Microbiol. Lett. 221, 221-226 https://doi.org/10.1016/S0378-1097(03)00182-4
  15. Pasternak, C. A. (1988) A novel role of $Ca^{2+}$ and $Zn^{2+}$: protection of cells against membrane damage. Biosci. Rep. 8, 579-583 https://doi.org/10.1007/BF01117337
  16. Lee, H. I. and Cha, J. S. (1998) Cloning of a DNA fragment specific to Pseudomonas tolaasii causing bacterial brown blotch disease of oyster mushroom (Pleurotus ostreatus). Kor. J. Plant Pathol. 14, 177-183
  17. Park, K. S. (1998) Increase in hemolytic and channel-forming activities of tolaasin by multimerization. M.S. Thesis. Chungbuk Nat'l Univ
  18. Hwang, P. M. and Vogel, H. J. (1998) Structure-function relationships of antimicrobial peptides. Biochem. Cell Biol. 76, 235-246 https://doi.org/10.1139/bcb-76-2-3-235
  19. Saberwal, G. and Nagaraj, R. (1994) Cell-lytic and antibacterial peptides that act by perturbing the barrier function of membranes: facets of their conformational features, structurefunction correlations and membrane-perturbing abilities. Biochim. Biophys. Acta 1197, 109-131 https://doi.org/10.1016/0304-4157(94)90002-7
  20. Bashford, C. L., Menestrina, G., Henkart, P. A. and Pasternak, C. A. (1988) Cell damage by cytolysin: spontaneous recovery and reversible inhibition by divalent cations. J. Immunol. 141, 3965-3974
  21. Alder, G. M., Arnold, W. M., Bashford, C. L., Drake, A. F., Pasternak, C. A. and Zimmermann, U. (1991) Divalent cationsensitive pores formed by natural and synthetic melittin and by Triton X-100. Biochim. Biophys. Acta 1061, 111-120 https://doi.org/10.1016/0005-2736(91)90275-D
  22. Bashford, C. L., Alder, G. M., Menestrina, G., Micklem, K. J., Murphy, J. J. and Pasternak, C. A. (1986) Membrane damage by hemolytic viruses, toxin, complement, and other cytotoxic agents; a common mechanism blocked by divalent cations. J. Biol. Chem. 261, 9300-9308
  23. Ishiura, S., Matsuda, K., Koizumi, H., Tsukahara, T., Arahata, K. and Sugita, H. (1990) Calcium is essential for both the membrane binding and lytic activity of pore-forming protein (perforin) from cytotoxic T-lymphocyte. Mol. Immunol. 27, 803-807 https://doi.org/10.1016/0161-5890(90)90090-M