跳转至内容
Merck
CN
  • pH-Induced molten globule state of Rhizopus niveus lipase is more resistant against thermal and chemical denaturation than its native state.

pH-Induced molten globule state of Rhizopus niveus lipase is more resistant against thermal and chemical denaturation than its native state.

Cell biochemistry and biophysics (2012-01-05)
Gulam Rabbani, Ejaz Ahmad, Nida Zaidi, Sadaf Fatima, Rizwan Hasan Khan
摘要

Here, we have characterized four pH-dependent states: alkaline state, "B" (pH 9.0), native state, "N" (pH 7.4), acid-induced state, "A" (pH 2.2) and molten globule state, "MG" (pH 1.8) of Rhizopus niveus lipase (RNL) by CD, tryptophanyl fluorescence, ANS binding, DLS, and enzyme activity assay. This "MG" state lacks catalytic activity and tertiary structure but it has native-like significant secondary structure. The "R (h)" of all the four states of RNL obtained from DLS study suggests that the molecular compactness of the protein increases as the pH of solution decreases. Kinetic analysis of RNL shows that it has maximum catalytic efficiency at state "B" which is 15-fold higher than state "N." The CD and tryptophanyl fluorescence studies of RNL on GuHCl and temperature-induced unfolding reveal that the "MG" state is more stable than the other states. The DSC endotherms of RNL obtained at pH 9.0, 7.4, and 2.2 were with two transitions, while at pH 1.8 it showed only a single transition.

材料
货号
品牌
产品描述

Sigma-Aldrich
8-苯胺基-1-萘磺酸 铵盐, for fluorescence, ≥97.0% (HPLC)
Sigma-Aldrich
8-苯胺基-1-萘磺酸
Sigma-Aldrich
8-苯胺基-1-萘磺酸 半镁盐 水合物, for fluorescence, ≥95.0% (T)
Sigma-Aldrich
8-苯胺基-1-萘磺酸 铵盐, technical, ≥90% (NT)
Sigma-Aldrich
8-苯胺基-1-萘磺酸 半镁盐 水合物, for fluorescence, ≥95% (TLC)