New insight on 8-anilino-1-naphthalene sulfonic acid interaction with TgFNR for hydrophobic exposure analysis

Singh, K; Hussain, I; Mishra, V; Akhtar, MS

HERO ID

5018104

Reference Type

Journal Article

Year

2019

Language

English

PMID

30391427

HERO ID 5018104
In Press No
Year 2019
Title New insight on 8-anilino-1-naphthalene sulfonic acid interaction with TgFNR for hydrophobic exposure analysis
Authors Singh, K; Hussain, I; Mishra, V; Akhtar, MS
Journal International Journal of Biological Macromolecules
Volume 122
Page Numbers 636-643
Abstract The exposed hydrophobic patches of protein are widely detected through the binding by the fluorescent probes such as 1-anilino-8-naphthalene sulfonate (ANS), Nile Red (NR) and 1-(N-phenylamino) naphthalene, N-(1-Naphthyl) aniline (1NPN). Interestingly, at pH4, where the Toxoplasma gondii Ferredoxin-NADP(+) reductase (TgFNR) is stable, an exclusive binding and fluorescence emission was observed for ANS. To understand the underlying difference in the binding of ANS, NR and 1NPN; their effect on the protein structure was studied in detail. ANS was found to interact with TgFNR via electrostatic as well as hydrophobic interactions at pH4. NR and 1NPN did not show any such binding to TgFNR in the similar conditions, however showed strong hydrophobic interaction in the presence of NaCl or DSS (2, 2-dimethyl-2-silapentane-5-sulfonate). The subsequent structural studies suggest that ANS, NaCl and DSS induced partial unfolding of TgFNR by modulating ionic interactions of the enzyme, leading to the exposure of buried hydrophobic patches amicable for the binding by NR and 1NPN. The induced unfolding of TgFNR by ANS is unique and thus cautions to use the fluorescent dye as simple indicator to probe the exposed hydrophobic patches of the protein or its folding intermediates.
Doi 10.1016/j.ijbiomac.2018.10.208
Pmid 30391427
Wosid WOS:000456226700072
Url <Go to ISI>://WOS:000456226700072
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English
Keyword article; CGH buffer; 1-anilino-8-naphthalene sulfonate (ANS); Nile Red; Protein stability; Folding intermediates; Toxoplasma gondii; aniline; electrostatic interactions; enzymes; exposure assessment; fluorescence; fluorescent dyes; hydrophobic bonding; hydrophobicity; naphthalene; protein structure; sodium chloride; sulfonic acid