Keratinolytic activity of Bacillus megaterium F7-1, a feather-degrading mesophilic bacterium

Abstract

The aim of this study was to investigate environmental conditions affecting chicken feather degradation and keratinolytic enzyme production by Bacillus megaterium F7-1, a feather-degrading mesophilic bacterium. B. megaterium F7-1 degraded whole chicken feather completely within 7 days. The bacterium grew with an optimum at pH 7.0-11.0 and 25-40 degrees C, where maximum keratinolytic activity was also observed. The production of keratinolytic enzyme by B. megaterium F7-1 was inducible with feather. Keratinolytic enzyme production by B. megaterium F7-1 at 0.6% (w/v) skim milk was 468U/ml, which was about 9.4-fold higher than that without skim milk. The amount of keratinolytic enzyme production depended on feather concentrations. The degradation rate of autoclaved chicken feathers by cell-free culture supernatant was 26% after 24h of incubation, but the degradation of untreated chicken feathers was unsuccessful. B. megaterium F7-1 effectively degraded feather meal, duck feather and human nail, whereas human hair and sheep wool showed relatively low degradation rates. B. megaterium F7-1 presented high keratinolytic activity and was very effective in feather degradation, providing potential use for biotechnological processes of keratin hydrolysis.

Increased expression of keratinase and other peptidases by Candida parapsilosis mutants

“…Conversion generally requires significant energy inputs and also destroys certain amino acids (5). It follows that degradation of feather keratin by microorganisms represents an alternative method to improve the nutritional value of feather waste and to prevent environmental contamination (6). Keratinolytic enzymes are produced by fungi, the actinomycetes, and other bacteria and have been frequently isolated from soils (7,8).…”

Biosynthesis and Control of Keratinase in Recalcitrant Feather-Degrading Bacillus megaterium F7-1

“…Keratinase was assayed with feather keratin as a substrate, according to the method of Park and Son (2009). An appropriately enzyme solution (2 ml) was mixed with 3 ml of 0.06% feather …”

“…We have previously reported on the isolation and characterization of Bacillus megaterium F7-1, which is able to produce chicken feather-degrading keratinase (Park and Son, 2009;Son et al, 2004). The objective of this investigation was to study the nutritional conditions controlling keratinase biosynthesis in B.…”

Chrysosporium queenslandicum: a potent keratinophilic fungus for keratinous waste degradation

“…Environmental wastes are originated in enormous amount from many countries and contain a considerable amount of protein and carbon compounds (Park and Son 2009). The keratinous wastes are considered as the environmental pollutants (Werlang and Brandelli 2005;Kumawat et al 2016a).…”