Biosynthesis, purification, and biochemical properties of an alkaline-thermostable keratinase derived from Bacillus cereus J6
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17 mar 2025
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Publicado en línea: 17 mar 2025
Recibido: 30 oct 2024
Aceptado: 10 feb 2025
DOI: https://doi.org/10.2478/amns-2025-0831
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© 2025 Rongxian Zhang et al., published by Sciendo
This work is licensed under the Creative Commons Attribution 4.0 International License.
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Effects of chemicals on J6 keratinase
| Chemicals | Concentration | Relative activity (%) |
|---|---|---|
| Na+ | 5 mmol/L | 102.59±2.78 |
| K+ | 5 mmol/L | 99.03±2.93 |
| Mn2+ | 5 mmol/L | 106.73±2.25 |
| Ca2+ | 5 mmol/L | 122.56±2.19 |
| Mg2+ | 5 mmol/L | 131.81±5.14 |
| Zn2+ | 5 mmol/L | 118.52±3.52 |
| Cu2+ | 5 mmol/L | 60.87±4.53 |
| Al3+ | 5 mmol/L | 62.67±6.21 |
| Fe2+ | 5 mmol/L | 52.89±5.35 |
| Fe3+ | 5 mmol/L | 31.04±3.87 |
| Tween 20 | 1% | 115.67±3.14 |
| Tween 60 | 1% | 175.27±1.31 |
| Tween 80 | 1% | 150.16±2.31 |
| Triton X-100 | 1% | 106.06±0.52 |
| SDS | 1% | 84.30±2.56 |
| DTT | 1 mmol/L | 155.96±2.73 |
| EDTA | 1 mmol/L | 5.05±2.21 |
| PMSF | 1 mmol/L | Not detected |
Results of orthogonal experiment
| Number | A | B | C | D | Keratinase yield (U/mL) |
|---|---|---|---|---|---|
| 1 | 1 | 1 | 1 | 1 | 375.55±3.12 |
| 2 | 1 | 2 | 2 | 2 | 179.8±5.93 |
| 3 | 1 | 3 | 3 | 3 | 359.9±6.49 |
| 4 | 2 | 1 | 2 | 3 | 401.4±9.84 |
| 5 | 2 | 2 | 3 | 1 | 342.55±3.16 |
| 6 | 2 | 3 | 1 | 2 | 208.9±9.53 |
| 7 | 3 | 1 | 3 | 2 | 186.9±42 |
| 8 | 3 | 2 | 1 | 3 | 307.25±4.78 |
| 9 | 3 | 3 | 2 | 1 | 294.9±2.65 |
| K1 | 305.08 | 321.28 | 297.23 | 337.67 | |
| K2 | 317.62 | 276.53 | 292.03 | 192.86 | |
| K3 | 263.02 | 288.9 | 296.45 | 356.18 | |
| R | 54.6 | 32.38 | 5.2 | 163.32 | |
| Order of priority: D > A > B > C | |||||
| Optimal Combination: A2B1C1D3 | |||||
Orthogonal experimental design of four factors and three levels
| Level | Factor | |||
|---|---|---|---|---|
| A feather (g/L) | B Lactose (g/L) | C Urea (g/L) | D MgSO4 (g/L) | |
| 1 | 7.5 | 2.5 | 7.5 | 0.9 |
| 2 | 10 | 5 | 10 | 1 |
| 3 | 12.5 | 7.5 | 12.5 | 1.1 |
Purification of the keratinase produced by B_ cereus J6
| Procedures | Protein quantity (mg) | activity (U) | Specific activity (U/mg) | Purification fold | Recovery rate (%) |
|---|---|---|---|---|---|
| Supernatant | 53.25 | 24032 | 451.31 | 1.00 | 100 |
| ASP | 15.41 | 14256 | 925.19 | 2.05 | 59.32 |
| DEAE-650 M chromatography | 0.65 | 2739 | 4215.24 | 9.34 | 11.36 |
