Galleria mellonella lysozyme induces apoptotic changes in Candida albicans cells.
The greater wax moth Galleria mellonella has been increasingly used as a model host to determine Candida albicans virulence and efficacy of antifungal treatment. The G. mellonella lysozyme, similarly to its human counterpart, is a member of the c-type family of lysozymes that exhibits antibacterial and antifungal activity. However, in contrast to the relatively well explained bactericidal action, the mechanism of fungistatic and/or fungicidal activity of lysozymes is still not clear. In the present study we provide the direct evidences that the G. mellonella lysozyme binds to the protoplasts as well as to the intact C. albicans cells and decreases the survival rate of both these forms in a time-dependent manner. No enzymatic activity of the lysozyme towards typical chitinase and β-glucanase substrates was detected, indicating that hydrolysis of main fungal cell wall components is not responsible for anti-Candida activity of the lysozyme. On the other hand, pre-treatment of cells with tetraethylammonium, a potassium channel blocker, prevented them from the lysozyme action, suggesting that lysozyme acts by induction of programmed cell death. In fact, the C. albicans cells treated with the lysozyme exhibited typical apoptotic features, i.e. loss of mitochondrial membrane potential, phosphatidylserine exposure in the outer leaflet of the cell membrane, as well as chromatin condensation and DNA fragmentation.
Department of Immunobiology, Faculty of Biology and Biotechnology, Maria Curie-Sklodowska University, Akademicka 19 St., 20-033 Lublin, Poland.
Aneta
A
Sowa-Jasiłek
Department of Immunobiology, Faculty of Biology and Biotechnology, Maria Curie-Sklodowska University, Akademicka 19 St., 20-033 Lublin, Poland.
Agnieszka
A
Zdybicka-Barabas
Department of Immunobiology, Faculty of Biology and Biotechnology, Maria Curie-Sklodowska University, Akademicka 19 St., 20-033 Lublin, Poland.
Sylwia
S
Stączek
Department of Comparative Anatomy and Anthropology, Faculty of Biology and Biotechnology, Maria Curie-Sklodowska University, Akademicka 19 St., 20-033 Lublin, Poland.
Jerzy
J
Wydrych
Analytical Laboratory, Faculty of Chemistry, Maria Curie-Sklodowska University, M.C. Sklodowska Square 5, 20-031 Lublin, Poland.
Krzysztof
K
Skrzypiec
Department of Analytical Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7 St., 30-387 Krakow, Poland.
Paweł
P
Mak
Department of Molecular Biology, Faculty of Biology and Biotechnology, Maria Curie-Sklodowska University, Akademicka 19 St., 20-033 Lublin, Poland.
Kamil
K
Deryło
Department of Molecular Biology, Faculty of Biology and Biotechnology, Maria Curie-Sklodowska University, Akademicka 19 St., 20-033 Lublin, Poland.
Marek
M
Tchórzewski
Department of Immunobiology, Faculty of Biology and Biotechnology, Maria Curie-Sklodowska University, Akademicka 19 St., 20-033 Lublin, Poland. Electronic address: cytryna@poczta.umcs.lublin.pl.
Małgorzata
M
Cytryńska
D000818:Animals; D000935:Antifungal Agents / Q000494:pharmacology*; D017209:Apoptosis; D002176:Candida albicans / Q000187:drug effects* / Q000502:physiology; D007915:Lepidoptera / Q000201:enzymology*; D050296:Microbial Viability / Q000187:drug effects; D009113:Muramidase / Q000494:pharmacology*
D000935:Antifungal Agents; D009113:Muramidase
Apoptosis; Candida albicans; Galleria mellonella; Lysozyme; Phosphatidylserine externalization; Potassium channels