A new feather-degrading bacterium PKD 5 was isolated from feather dumping
soil and identified as Bacillus weihenstephanensis based on morphological and physiochemical
characteristics as well as 16S rRNA gene analysis. Extracellular keratinase was produced
during submerged aerobic cultivation in a medium containing chicken feather as sole
carbon and energy source and supplemented with salt solutions (NaCl 5.0, MgSO4 1.0,
K2HPO4 1.0, (NH4)2SO4, 2.0 g/l). The optimal conditions for keratinase production include
initial pH of 7.0, inoculum size of 2% (v/v), and cultivation at 40 °C. The maximum
keratinase production and keratinolytic activity of PKD 5 was achieved after 7 days of
fermentation under shaking condition (120 rpm). The enzyme has found application in
developing cost-effective feather by-products for feeds and fertilizers. The manuscript first
time describes B. weihenstephanensis PKD 5-mediated keratinase production under submerged
fermentation and whole chicken feather biodegradation.