A novel method for dissolution and stabilization of non-mulberry silk gland protein fibroin using anionic surfactant sodium dodecyl sulfate.
The importance of silk protein has increased because of its potential use as a natural biopolymer for tissue engineering and biomedical applications. In this report we show a novel and ecofriendly method for dissolution of gland silk protein fibroin. Non-mulberry silk fibroin from mature fifth instar larvae of Antheraea mylitta was found to be optimally soluble in 1% (w/v) anionic surfactant sodium dodecyl sulfate (SDS). Regenerated fibroin showed distinct bands of approximately 395 and 197 kDa on electrophoresis in non-reducing and reducing conditions, respectively. Enhanced fibroin dissolution via internalization of hydrophobic amino groups inside a hydrophilic amino acid core in the form of micelles was observed. Prolonged storage stability without gelation of SDS-extracted fibroin was seen. Atomic force microscopy showed micellar aggregation with mean micellar aggregation size of 8 nm. Circular dichroism spectroscopy revealed predominantly helical conformation due to surfactant addition with internal protein conformational changes as revealed by fluorescence spectroscopic studies.
Mandal
Biman B
BB
Department of Biotechnology, Indian Institute of Technology, Kharagpur, West Bengal 721302, India.
Kundu
S C
SC
D000818:Animals; D000838:Anions; D012831:Bombyx / Q000378:metabolism*; D005349:Fibroins / Q000737:chemistry* / Q000648:ultrastructure*; D011487:Protein Conformation; D011489:Protein Denaturation; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry*; D013501:Surface-Active Agents / Q000737:chemistry*
D000838:Anions; D013501:Surface-Active Agents; D012967:Sodium Dodecyl Sulfate; D005349:Fibroins