Endogenous proteolysis of the human erythrocyte membrane as studied by two-dimensional gel electrophoresis and electron spin resonance.
1. Endogenous proteolysis in human erythrocyte membranes was studied in human erythrocyte membranes incubated at 37 degrees C by monitoring changes in 2-D electrophoretic pattern of membrane polypeptides and in the spectra of maleimide-spin labeled membranes. 2. A strong effect of exogenous proteases derived from contaminating other blood elements was found, resulting in formation of specific spots on 2-D electropherograms, requiring very careful leukocyte removal in investigations of red cell membrane protein composition and proteolysis. 3. Studies of the effects of protease inhibitors and Ca2+ confirmed a complex pattern of endogenous red cell membrane proteolysis ("self-digestion") involving many substrates and enzymes. 4. A promoting effect of high concentrations (150 mM) of Ca2+ on endogenous red cell membrane proteolysis was found.
Gromov
P S
PS
Laboratory of Biochemical Genetics, U.S.S.R. Academy of Medical Sciences, Moscow.
Zakharov
S F
SF
Shishkin
S S
SS
Gaczyńska
M
M
Bartosz
G
G
Grzelińska
E
E
D001798:Blood Proteins / Q000378:metabolism*; D002118:Calcium / Q000494:pharmacology; D004578:Electron Spin Resonance Spectroscopy; D015180:Electrophoresis, Gel, Two-Dimensional; D004910:Erythrocyte Membrane / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D011480:Protease Inhibitors / Q000494:pharmacology
D001798:Blood Proteins; D011480:Protease Inhibitors; D002118:Calcium