稳定性/保质期:
Application A thermostable (thermophilic) extracellular metalloendopeptidase containing four calcium ions. Cofactors are zinc and calcium. This enzyme hydrolyzes protein bonds on the N-terminal side of hydrophobic amino acid residues, with a pH optimum of 8.0 and an optimal temperature for activity at 70 °C. It is considerably stable from pH 5 to 9.5.
Thermolysin has low cleavage specificity, producing numerous short fragments suitable for sequencing. Its preferential cleavage pattern follows the sequence X-cleavage-Y-Z, where X can be any amino acid; Y can be Leu, Phe, Ile, Val, Met, or Ala; and Z is any amino acid except Pro. Cleavage at the N-terminal of Leu is preferred over that of Phe, which in turn is preferred over others.
Often used for limited proteolysis, peptide mapping, and studies of protein structure and conformational changes. One unit will hydrolyze casein to produce a color equivalent to 1.0 μmole (181 μg) of tyrosine per minute at pH 7.5 and 37 °C using the Folin-Ciocalteu reagent.