Dimerization stabilizes the pore-forming toxin aerolysin in solution

van der Goot, FG; Ausio, J; Wong, KR; Pattus, F; Buckley, JT

HERO ID

1483067

Reference Type

Journal Article

Year

1993

Language

English

PMID

7688743

HERO ID 1483067
In Press No
Year 1993
Title Dimerization stabilizes the pore-forming toxin aerolysin in solution
Authors van der Goot, FG; Ausio, J; Wong, KR; Pattus, F; Buckley, JT
Journal Journal of Biological Chemistry
Volume 268
Issue 24
Page Numbers 18272-18279
Abstract Aerolysin is a channel-forming protein secreted as a protoxin by Aeromonas hydrophila. Analytical centrifugation measurements showed that proaerolysin is a dimer in solution, and this was confirmed by chemical cross-linking with dimethyl suberimidate. Dissociation of proaerolysin with low concentrations of SDS resulted in the loss of tertiary structure, assessed by near ultraviolet circular dichroism. This was accompanied by an increase in the protein's ability to bind the hydrophobic dye 1-anilino-8-naphthalene sulfonate, as well as by increased sensitivity to proteolytic degradation. However, the monomer was not fully unfolded by the detergent, as the tryptophans remained in a hydrophobic environment, and the secondary structure measured by far ultraviolet circular dichroism did not seem to be affected. Aerolysin, the active form of the protein, was also shown to be a dimer, and its stability was found to be no different from the stability of the protoxin dimer. Substituting tryptophan 371 or tryptophan 373 with leucine greatly reduced the stability of dimeric proaerolysin. These substitutions are known to increase the protein's ability to oligomerize, supporting the conclusion that dimer dissociation is necessary for oligomerization to occur.
Doi 10.1016/S0021-9258(17)46840-2
Pmid 7688743
Wosid WOS:A1993LT74300092
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English
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