Separation and purification of a keratinase as pesticide against root-knot nematodes

• Published in: World journal of microbiology & biotechnology Vol. 27; no. 9; pp. 2147 - 2153
• Main Authors: Yue, Xiao Yu, Zhang, Bin, Jiang, Dan Dan, Liu, Yan Juan, Niu, Tian Gui
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.09.2011; Springer; Springer Nature B.V
• Subjects: Agricultural biotechnology; Ammonium; Applied Microbiology; Bacillus; Biochemistry; Biological and medical sciences; Biomedical and Life Sciences; Biotechnology; Chromatography; Entomology; Environmental Engineering/Biotechnology; Enzymes; Fundamental and applied biological sciences. Psychology; Keratin; Life Sciences; Liquid chromatography; Meloidogyne incognita; Microbiology; Microorganisms; Minors; Natural products; Nematoda; Nematodes; Original Paper; Pesticides; Proteins; Studies; Sulfates; China; Keratinase; Pesticide; Purification; Separation; Root; Pesticides; Bacillaceae; Bacillales; Meloidogyne incognita; Bacillus; Helmintha; Bacteria; Nemathelminthia; Invertebrata; Nematoda
• ISSN: 0959-3993; 1573-0972
• DOI: 10.1007/s11274-011-0680-z

A new alkaline keratinase, which could kill Meloidogyne incognita (a root-knot nematode) was separated and purified from Bacillus sp. 50-3 in this study. The solid ammonium sulfate was selected to precipitate the enzyme and its proper adding mass was also determined. After solid ammonium sulfate precipitation and liquid chromatography on DEAE-Sephadex-A50 column, there was 17.7-fold purification with a yield of 46.5%, as determined by azokeratin as substrate. The purification effect was determined through SDS-PAGE and the molecular weight of the enzyme was found to be 27,423 Da by the MALDI-TOF-MS. When the second-stage juveniles of Meloidogyne incognita were exposed to 50 μg/ml of keratinase solution, 98.5% of Meloidogyne incognita mortality rates were obtained compared to control after 24 h. Its simple purification step and high yield from the cheap medium affords this keratinase great biotechnological potential, especially in controlling root-knot nematodes such as Meloidogyne incognita . To the best of our knowledge, this study is the first report that uses keratinase as a pesticide.