Directed evolution driving the generation of an efficient keratinase variant to facilitate the feather degradation

Bioresources and Bioprocessing

Table 3 Comparison of amino acids in feather degradation products

Amino acid	Concentration (mg/L)
Amino acid	WT (12 h)	Variant T18 (12 h)	KerSMD and KerSMF (48 h) (Peng et al. 2019)	Bacillus pumilus AR57 keratinase (Jagadeesan et al. 2020)
asp	64.66 ± 1.84	44.05 ± 1.47	15.55 ± 1.09	0.612
glu	245.91 ± 6.95	122.94 ± 3.16	20.19 ± 0.13	1.242
ser	10.00 ± 1.08	12.99 ± 0.66	14.61 ± 0.18	9.805
his	44.05 ± 0.39	269.73 ± 0.45	ND	4.794
gly	136.19 ± 7.33	219.54 ± 6.42	14.34 ± 0.24	1.421
thr	464.77 ± 56.77	917.09 ± 24.37	15.74 ± 0.22	3.514
arg	8.8 ± 0.61	25.09 ± 0.43	22.13 ± 0.49	14.110
ala	504.30 ± 5.88	23.80 ± 0.14	10.05 ± 0.28	0.517
tyr	195.87 ± 0.89	387.42 ± 5.94	171.53 ± 0.42	18.789
cys	10.82 ± 1.49	14.56 ± 1.47	ND	ND
val	148.99 ± 8.97	389.84 ± 22.32	207.51 ± 0.29	8.716
met	187.58 ± 11.44	370.51 ± 15.36	0 ± 0.41	7.684
phe	348.35 ± 1.36	688.07 ± 14.47	183.73 ± 0.21	33.153
ile	18.99 ± 0.94	55.39 ± 1.64	72.96 ± 0.49	4.749
leu	91.94 ± 1.88	349.90 ± 8.14	126.61 ± 0.73	7.083
lys	510.48 ± 5.08	1066.35 ± 13.87	20.94 ± 0.73	3.772
pro	28.14 ± 2.86	14.43 ± 1.70	ND	ND