Riffel Alessandro, Lucas Françoise, Heeb Philipp, Brandelli Adriano
Departamento de Ciência de Alimentos, ICTA, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, 91501-970, Porto Alegre, Brazil.
Arch Microbiol. 2003 Apr;179(4):258-65. doi: 10.1007/s00203-003-0525-8. Epub 2003 Feb 28.
A novel feather-degrading microorganism was isolated from poultry waste, producing a high keratinolytic activity when cultured on broth containing native feather. Complete feather degradation was achieved during cultivation. The bacterium presents potential use for biotechnological processes involving keratin hydrolysis. Chryseobacterium sp. strain kr6 was identified based on morphological and biochemical tests and 16S rRNA sequencing. The bacterium presented optimum growth at pH 8.0 and 30 degrees C; under these conditions, maximum feather-degrading activity was also achieved. Maximum keratinase production was reached at 25 degrees C, while concentration of soluble protein was similar at both 25 and 30 degrees C. Reduction of disulfide bridges was also observed, increasing with cultivation time. The keratinase of strain kr6 was active on azokeratin and azocasein as substrates, and presented optimum pH and temperature of 7.5 and 55 degrees C, respectively. The keratinase activity was inhibited by 1,10-phenanthroline, EDTA, Hg(2+), and Cu(2+) and stimulated by Ca(2+).
从家禽粪便中分离出一种新型羽毛降解微生物，该微生物在含有天然羽毛的肉汤中培养时具有较高的角蛋白分解活性。在培养过程中可实现羽毛的完全降解。该细菌在涉及角蛋白水解的生物技术过程中具有潜在应用价值。基于形态学、生化测试及16S rRNA测序鉴定该细菌为 Chryseobacterium sp. 菌株kr6。该细菌在pH 8.0和30℃条件下生长最佳；在此条件下，也能实现最大的羽毛降解活性。在25℃时达到最大角蛋白酶产量，而在25℃和30℃时可溶性蛋白浓度相似。还观察到二硫键减少，且随培养时间增加。菌株kr6的角蛋白酶以偶氮角蛋白和偶氮酪蛋白为底物时具有活性，其最佳pH和温度分别为7.5和55℃。角蛋白酶活性受到1,10 - 菲啰啉、EDTA、Hg(2+)和Cu(2+)抑制，而受到Ca(2+)刺激。
