In-silico study of bacterial keratinase and optimization of extraction procedure for keratin from Country chicken and Indian blue rock pigeon feathers

Abstract

Keratin, a versatile bioprotein, has seen a tremendous industrial exploitation due to its outstanding biodegradability and biocompatibility nature. Keratin is primarily derived from substrates such as feathers, nails, horns, beaks, hair and bovine hoofs. The generation of chicken and pigeon feather wastes has risen over the years in Vellore. When it is not discarded properly, this acts as a major root cause for the dissemination of various diseases to humans. The primary aim of this research is to remediate these wastes by extracting the keratin and to prove that beta-mercaptoethanol enhances keratinase activity by in-silico approach for degradation of these wastes. In light of this, the feathers from the dumped sites of Vellore were exploited and the keratin was extracted from country chicken and pigeon feathers which yields a concentration of 3.44 mg/L and 2.8 mg/L of keratin. This extraction procedure is significantly more cost-effective and yields more keratin than earlier approaches. The crystallographic structures of keratin were examined by X-ray diffraction studies. The functional group of the keratin was analyzed by using Fourier-transform infrared spectroscopy and confirmed the presence of cysteine-cystine, glutamic acid and tryptophan. The mode of action and degree of effectiveness of keratin were studied using Lipinski's rule of 5. In addition, the Protein Data Bank was used to retrieve the keratinase structure of Meiothermus taiwanensis WR-220, which has the National Center for Biotechnology Information (NCBI) and Protein Data Bank (PDB) accession ID-5WSL and the enzyme's tertiary structure was studied with the SwissModel tool. Using Autodock, beta-mercaptoethanol was docked with keratinase and enzyme-ligand in-silico interactions prove that ligand enhances the activity of microbial keratinase.