The effect of oxidative stress induced by t-butyl hydroperoxide on the structural dynamics of membrane proteins of Chinese hamster fibroblasts.
A method based on the measurement at room temperature of tryptophan phosphorescence (RTTP) gives the unique possibility to investigate the dynamic structure of membrane proteins without their isolation from cells. This method was used to study the influence of tert- butyl hydroperoxide (t -BHP) on Chinese hamster fibroblasts. The treatment of fibroblasts with t -BHP in a concentration range of 0. 5-2 m m for 60 min caused an increase of frequency and amplitude of membrane protein motions with lifetimes of hundreds miliseconds (a decrease of RTTP tau(2)). In parallel, cell viability was studied by trypan blue exclusion test and the content of thiobarbituric acid reactive substances was measured in cells. The dependences of the RTTP tau(2)and cell viability on t -BHP concentration were similar. Contrary to this, t -BHP did not induce the activation of lipid peroxidation processes in cells. This indicates that cell death is connected with the excessive increase of intramolecular dynamics of membrane proteins during t -BHP action.
Mazhul
V
V
Institute of Photobiology, National Academy of Sciences of Belarus, Minsk, Belarus.
Shcherbin
D
D
Zavodnik
I
I
Rekawiecka
K
K
Bryszewska
M
M
D000818:Animals; D016466:CHO Cells / Q000166:cytology / Q000378:metabolism; D002470:Cell Survival / Q000502:physiology; D006224:Cricetinae; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D007700:Kinetics; D015227:Lipid Peroxidation / Q000187:drug effects / Q000502:physiology; D008163:Luminescent Measurements; D008565:Membrane Proteins / Q000378:metabolism*; D016877:Oxidants / Q000494:pharmacology*; D018384:Oxidative Stress / Q000187:drug effects / Q000502:physiology*; D013696:Temperature; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis; D014364:Tryptophan; D020122:tert-Butylhydroperoxide / Q000494:pharmacology*
D008565:Membrane Proteins; D016877:Oxidants; D017392:Thiobarbituric Acid Reactive Substances; D014364:Tryptophan; D020122:tert-Butylhydroperoxide