Institute of Chemical Industry of Forest Products, CAF; National Engineering Laboratory for Biomass Chemical Utilization; Key and Open Laboratory of Forest Chemical Engineering, SFA; Key Laboratory of Biomass Energy and Material, Nanjing, Jiangsu Province 210042, PR China E-mail:
Water Sci Technol. 2022 Aug;86(4):777-786. doi: 10.2166/wst.2022.237.
New Bacillus sp. strains with spore-laccase activity were isolated from rotten wood and soil samples and were identified as Bacillus sp. FM-78 and Bacillus paramycoides FM-86 by 16S rDNA gene sequence analysis. Both laccases were stable at broad pH range and high temperature. The laccase of strain FM-78 showed preferable activity and stability, with no loss of activity after 7 days incubation at pH 9.0, and 20.36% of its initial activity obtained after 10 h at 80 °C. 1 mmol/L EDTA, NaN and SDS resulted in about 46-59% inactivation and strongly inhibition (87.88%) was caused by 1 mmol/L L-cysteine. However, the spore laccase could tolerate towards 0.5 mol/L NaCl as well as 10% of organic solvents. Reactive black 5, reactive blue 19 and crystal violet were decolorized by the spore laccase in the absence of mediator. The decolorization process was efficiently promoted with the presence of acetosyringone, and the color removal ratio was more than 80% in 1 h with the pH values of 6.6 or 9.0. Finally, the above unusual properties of Bacillus sp. spore laccase indicated it as a potential candidate in the dye decolorization in an ecofriendly and cost-effective way.
从腐烂的木材和土壤样本中分离到具有孢子漆酶活性的新型芽孢杆菌菌株，并通过 16S rDNA 基因序列分析鉴定为芽孢杆菌 FM-78 和芽孢杆菌 paramycoides FM-86。两种漆酶在较宽的 pH 范围和高温下均稳定。菌株 FM-78 的漆酶表现出较好的活性和稳定性，在 pH 9.0 下孵育 7 天后没有失去活性，在 80°C 下孵育 10 小时后仍保持初始活性的 20.36%。1 mmol/L EDTA、NaN 和 SDS 导致约 46-59%的失活，而 1 mmol/L L-半胱氨酸则导致强烈抑制（87.88%）。然而，孢子漆酶可以耐受 0.5 mol/L NaCl 和 10%的有机溶剂。在没有介体的情况下，反应黑 5、反应蓝 19 和结晶紫可被孢子漆酶脱色。在乙酰丁香酮的存在下，脱色过程得到有效促进，在 pH 值为 6.6 或 9.0 时，1 小时内的去除率超过 80%。最后，芽孢杆菌孢子漆酶的这些异常特性表明它是一种潜在的候选酶，可用于环保且经济有效的染料脱色。
