The state of tryptophan-containing sites of human, bovine and rabbit plasminogens with changing solution pHs

Abstract

• 1.

  1. The state of tryptophan-containing sites is proved to be stable by intrinsic tryptophan fluorescence with pH 5–8, 7–9, and 6–9 in human, rabbit and bovine plasminogen molecules, respectively.

• 2.

  2. With pH < 5.0 tryptophan-containing sites of human zymogen (in contrast to rabbit and bovine ones) undergo conformational transitions.

• 3.

  3. With the shift of solution pH from 9 to 12 tryptophan-containing sites of human and rabbit plasminogens are partially disorganized, while tryptophanyls become more available for solvent.

• 4.

  4. Tryptophan-containing sites of bovine plasminogen molecules are less mobile in structure during changes of solution pH.