Open AccessAnomalous electrophoretic behaviour of the major cysteine proteinase (cruzipain) from Trypanosoma cruzi in relation to its apparent molecular mass
Author(s) -
Martínez Javier,
Cazzulo Juán José
Publication year - 1992
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1992.tb05370.x
Subject(s) - molecular mass , glycosylation , polyacrylamide gel electrophoresis , biochemistry , enzyme , cysteine , electrophoresis , gel electrophoresis , chemistry , acrylamide , chromatography , biology , organic chemistry , copolymer , polymer
The molecular mass of cruzipain, the major cysteine proteinase from Trypanosoma cruzi epimastigotes, is 36.3 kDa as calculated from its sequence; this value can increase to about 41 kDa if the three potential N ‐glycosylation sites are glycosylated in vivo. Yet the apparent molecular mass of the enzyme, as determined by SDS‐polyacrylamide gel electrophoresis, has been reported in a range of values from 60 to 40 kDa. We show that the purified enzyme had apparent molecular masses ranging from 51 to 33 kDa, depending on the experimental conditions. This variation is likely to be due to both N ‐glycosylation and the presence of several disulfide bridges, which make electrophoretic mobility dependent on acrylamide concentration, and reduction and/or boiling of the sample.