Plasma membrane damage to Candida albicans caused by chlorine dioxide (ClO2).
OBJECTIVE
To investigate the plasma membrane damage of chlorine dioxide (ClO(2)) to Candida albicans ATCC10231 at or below the minimal fungicidal concentration (MFC).


RESULTS
ClO(2) at MFC or below was adopted to treat the cell suspensions of C. albicans ATCC10231. Using transmission electron microscopy, no visible physiological alteration of cell shape and plasma membrane occurred. Potassium (K(+)) leakages were significant; likewise, it showed time- and dose-dependent increases. However, adenosine triphosphate (ATP) leakages were very slight. Research shows that when 99% of the cells were inactivated, the leakage was measured at 0.04% of total ATP. Compared with the mortality-specific fluorescent dye of DiBAC(4)(3), majority of the inactivated cells were poorly stained by propidium iodide, another mortality-specific fluorescent dye which can be traced by flow cytometry.


CONCLUSIONS
At or below MFC, ClO(2) damages the plasma membranes of C. albicans mainly by permeabilization, rather than by the disruption of their integrity. K(+) leakage and the concomitant depolarization of the cell membrane are some of the critical events.


CONCLUSIONS
These insights into membrane damages are helpful in understanding the action mode of ClO(2).
Wei
M-K
MK
South China Sea Institute of Oceanology, Chinese Academy of Sciences; and Guangdong Institute of Microbiology, Guangzhou, China.
Wu
Q-P
QP
Huang
Q
Q
Wu
J-L
JL
Zhang
J-M
JM
D000255:Adenosine Triphosphate / Q000378:metabolism; D002176:Candida albicans / Q000187:drug effects* / Q000648:ultrastructure*; D002462:Cell Membrane / Q000187:drug effects* / Q000648:ultrastructure*; D002463:Cell Membrane Permeability / Q000187:drug effects; D017606:Chlorine Compounds / Q000494:pharmacology*; D004202:Disinfectants / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D050296:Microbial Viability; D046529:Microscopy, Electron, Transmission; D010087:Oxides / Q000494:pharmacology*; D011188:Potassium / Q000378:metabolism; D011419:Propidium / Q000378:metabolism; D013194:Staining and Labeling; D013997:Time Factors
D017606:Chlorine Compounds; D004202:Disinfectants; D010087:Oxides; D011419:Propidium; C025109:chlorine dioxide; D000255:Adenosine Triphosphate; D011188:Potassium