Similar articles

Abstract: A new feather-degrading bacterium was isolated from a local feather waste site and identified as Bacillus subtilis based on morphological, physiochemical, and phylogenetic characteristics. Screening for mutants with elevated keratinolytic activity using N-methyl-N′-nitro-N-nitrosoguanidine mutagenesis resulted in a mutant strain KD-N2 producing keratinolytic activity about 2.5 times that of the wild-type strain. The mutant strain produced inducible keratinase in different substrates of feathers, hair, wool and silk under submerged cultivation. Scanning electron microscopy studies showed the degradation of feathers, hair and silk by the keratinase. The optimal conditions for keratinase production include initial pH of 7.5, inoculum size of 2% (v/v), age of inoculum of 16 h, and cultivation at 23 °C. The maximum keratinolytic activity of KD-N2 was achieved after 30 h. Essential amino acids like threonine, valine, methionine as well as ammonia were produced when feathers were used as substrates. Strain KD-N2, therefore, shows great promise of finding potential applications in keratin hydrolysis and keratinase production.

[1] Anbu, P., Gopinath, S.C.B., Hilda, A., Priya, L.T., Annadurai, G., 2005. Purification of keratinase from poultry farm isolate—Scopulariopsis brevicaulis and statistical optimization of enzyme activity. Enzyme Microb. Technol., 36(5/6):639-647.

[2] El-Refai, H.A., AbdelNaby, M.A., Gaballa, A., El-Araby, M.H., Abdel Fattah, A.F., 2005. Improvement of the newly isolated Bacillus pumilus FH9 keratinolytic activity. Process Biochem., 40(7):2325-2332.

[3] Friedrich, J., Gradisar, H., Vrecl, M., Pogacnik, A., 2005. In vitro degradation of porcine skin epidermis by a fungal keratinase of Doratomyces microsporus. Enzyme Microb. Technol., 36(4):455-460.

[4] Gessesse, A., Hatti-Kaul, R., Gashe, B.A., Mattiasson, B., 2003. Novel alkaline proteases from alkaliphilic bacteria grown on chicken feather. Enzyme Microb. Technol., 32(5):519-524.

[5] Gousterova, A., Braikova, D., Goshev, I., Christov, P., Tishinov, K., Vasileva-Tonkova, E., Haertle, T., Nedkov, P., 2005. Degradation of keratin and collagen containing wastes by newly isolated thermoactinomycetes or by alkaline hydrolysis. Lett. Appl. Microbiol., 40(5):335-340.

[6] Gradišar, H., Kern, S., Friedrich, J., 2000. Keratinase of Doratomyces microsporus. Appl. Microbiol. Biotechnol., 53(2):196-200.

[7] Gradišar, H., Friedrich, J., Križaj, I., Jerala, R., 2005. Similarities and specificities of fungal keratinolytic proteases: comparison of keratinase of Paecilomyces marquandii and Doratomyces microsporus to some known proteases. Appl. Environ. Microbiol., 71(7):3420-3426.

[8] Grazziotin, A., Pimentel, F.A., de Jong, E.V., Brandelli, A., 2006. Nutritional improvement of feather protein by treatment with microbial keratinase. Anim. Feed Sci. Technol., 126(1-2):135-144.

[9] Gupta, R., Ramnani, P., 2006. Microbial keratinase and their prospective application: an overview. Appl. Microbiol. Biotechnol., 70(1):21-33.

[10] Ignatova, Z., Gousterova, A., Spassov, G., Nedkov, P., 1999. Isolation and partial characterization of extracellular keratinase from a wool degrading thermophilic actinomycete strain Thermoactinomyces candidus. Can. J. Microbiol., 45(3):217-222.

[11] Kim, J.M., Lim, W.J., Suh, H.J., 2001. Feather-degrading Bacillus species from poultry waste. Process Biochem., 37(3):287-291.

[12] Kumar, S., Tamura, K., Nei, M., 2004. MEGA3: integrated software for molecular evolutionary genetics analysis and sequence alignment. Brief. Bioinform., 5(2):150-163.

[13] Kunert, J., 2000. Physiology of Keratinophilic Fungi. In: Kushwaha, R.K.S., Guarro, J. (Eds.), Biology of Dermatophytes and Other Keratinophilic Fungi. Revista Iberoamericana de Micología, Bilbao, p.77-85.

[14] Langeveld, J.P.M., Wang, J.J., van de Wiel, D.F.M., Shih, G.C., Garssen, G.J., Bossers, A., Shih, J.C.H., 2003. Enzymatic degradation of prion protein in brain stem from infected cattle and sheep. J. Infect. Dis., 188(11):1782-1789.

[15] Liu, Z.T., 1984. Bacillus and Cocci. In: Bergey’s Manual of Systematic Bacteriology. Williams and Wilkins, Baltimore, Vol. 1, p.729-796.

[16] Macedo, A.J., da Silva, W.O.B., Gava, R., Driemeier, D., Henriques, J.A.P., Termignoni, C., 2005. Novel keratinase from Bacillus subtilis S14 exhibiting remarkable dehairing capabilities. Appl. Environ. Microbiol., 71(1):594-596.

[17] Manczinger, L., Rozs, M., Vagvolgyi, C., Kevei, F., 2003. Isolation and characterization of a new keratinolytic Bacillus licheniformis strain. World J. Microbiol. Biotechnol., 19(1):35-39.

[18] Onifade, A.A., A1-Sane, N.A., Al-Musallam, A.A., Al-Zarban, S., 1998. Potentials for biotechnological applications of keratin-degrading microorganisms and their enzymes for nutritional improvement of feathers and other keratins as livestock feed resources. Biores. Technol., 66(1):1-11.

[19] Ramnani, P., Gupta, R., 2004. Optimization of medium composition for keratinase production on feather by Bacillus licheniformis RG1 using statistical methods involving response surface methodology. Biotechnol. Appl. Biochem., 40(11):191-196.

[20] Riffel, A., Lucas, F.S., Heeb, P., Brandelli, A., 2003. Characterization of a new keratinolytic bacterium that completely degrades native feather keratin. Arch. Microbiol., 179(4):258-265.

[21] Rozs, M., Manczinger, L., Vagvolgyi, C., Kevei, F., 2001. Secretion of a trypsin-like thiol protease by a new keratinolytic strain of Bacillus licheniformis. FEMS Microbiol. Lett., 205(2):221-224.

[22] Sambrook, J., Fritsch, E.F., Maniatis, T., 1989. Molecular Cloning: A Laboratory Manual, 2nd Ed. Cold Spring Harbor Laboratory, Cold Spring Harbor, New York.

[23] Suntornsuk, W., Suntornsuk, L., 2003. Feather degradation by Bacillus sp. FK 46 in submerged cultivation. Biores. Technol., 86(3):239-243.

[24] Takami, H., Nogi, Y., Horikoshi, K., 1999. Reidentification of the keratinase-producing facultatively alkaliphilic Bacillus sp. AH-101 as Bacillus halodurans. Extremophiles, 3(4):293-296.

[25] Tan, T.W., Zhang, M., Wang, B.W., Ying, C.H., Deng, L., 2003. Screening of high lipase producing Candida sp. and production of lipase by fermentation. Process Biochem., 39(4):459-465.

[26] Thompson, J.D., Gibson, T.J., Plewniak, F., Jeanmougin, F., Higgins, D.G., 1997. The ClustalX windows interface: flexible strategies for multiple sequence alignment aided by quality analysis tools. Nucleic. Acids Res., 25(24):4876-4882.

[27] Wang, C.L., Li, D.F., Lu, W.Q., Wang, Y.H., Lai, C.H., 2004. Influence of cultivating conditions on the alpha-galactosidase biosynthesis from a novel strain of Penicillium sp. in solid-state fermentation. Lett. Appl. Microbiol., 39(4):369-375.

[28] Wawrzkiewicz, K., Lobarzewski, J., Wolski, T., 1987. Intracellular keratinase of Trichophyton gallinae. Med. Mycol., 25(4):261-268.

[29] Williams, C.M., Richter, C.S., Mackenzie, J.M., Shih, J.C.H., 1990. Isolation, identification, and characterization of a feather-degrading bacterium. Appl. Environ. Microbiol., 56(6):1509-1515.

[30] Williams, C.M., Lee, C.G., Garlich, J.D., Shih, J.C.H., 1991. Evaluation of a bacterial feather fermentation product, feather-lysate, as a feed protein. Poultry Sci., 70(1):85-94.