TY  - JOUR
AB  - l-Amino acid oxidases (l-AAO) catalyze the oxidative deamination of l-amino acids to the corresponding α-keto acids. The non-covalently bound cofactor FAD is reoxidized by oxygen under formation of hydrogen peroxide. We expressed an active l-AAO from the fungus Rhizoctonia solani as a fusion protein in E. coli. Treatment with small amounts of the detergent sodium dodecyl sulfate (SDS) stimulated the activity of the enzyme strongly. Here, we investigated whether other detergents and amphiphilic molecules activate 9His-rsLAAO1. We found that 9His-rsLAAO1 was also activated by sodium tetradecyl sulfate. Other detergents and fatty acids were not effective. Moreover, effects of SDS on the oligomerization state and the protein structure were analyzed. Native and SDS-activated 9His-rsLAAO1 behaved as dimers by size-exclusion chromatography. SDS treatment induced an increase in hydrodynamic radius as observed by size-exclusion chromatography and dynamic light scattering. The activated enzyme showed accelerated thermal inactivation and an exposure of additional protease sites. Changes in tryptophan fluorescence point to a more hydrophilic environment. Moreover, FAD fluorescence increased and a lower concentration of sulfites was sufficient to form adducts with FAD. Taken together, these data point towards a more open conformation of SDS-activated l-amino acid oxidase facilitating access to the active site.
DA  - 2017
DO  - 10.3390/molecules22122272
KW  - l-amino acid oxidase
KW  - activation
KW  - SDS
KW  - active conformation
KW  - conformational change
KW  - photon correlation spectroscopy (PCS)
LA  - eng
IS  - 12
PY  - 2017
SN  - 1420-3049
T2  - Molecules
TI  - Activation of recombinantly expressed l-Amino Acid Oxidase from Rhizoctonia solani by Sodium Dodecyl Sulfate
UR  - https://nbn-resolving.org/urn:nbn:de:0070-pub-29160837
Y2  - 2024-11-24T04:25:45
ER  -