A novel laccase from the ascomycete Melanocarpus albomyces was isolated, purified and characterized. The ultraviolet-visible absorption and electron paramagnetic resonance spectra indicated that the three types of coppers were present. Redox potential of the T1 copper of M. albomyces laccase ws determined to be 0.46 ± 0.01 V. The enzyme has very interesting pH and temperature behaviour. It had a pH optimum measured with guaiacol at neutral and slightly alkalic pH and substantial activity still at pH 8. The laccase showed very good thermostability, retaining full activity for two hours at 60 °C. The gene encoding the M. albomyces laccase was isolated and sequenced. The length of the open reading frame of the M. albomyces laccase was 623 amino acid residues. The copper binding residues were well conserved and the amino acid sequence had high homology to other ascomycete laccases. Interestingly the secreted laccase was processed both from the amino and carboxy terminus. The laccase was also crystallized with all four coppers present.
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机译：分离出来自Ascomycete Melanocarpus Abomyces的新型漆酶，纯化和表征。紫外线可见吸收和电子顺磁共振谱表明存在三种类型的涂布器。用于M的T1铜的氧化还原电位。Abomyces漆酶WS确定为0.46±0.01 V.酶具有非常有趣的pH和温度行为。它具有在中性的愈合菌和略微碱性pH和仍然在pH8时的碱性pH和大量活性测量的pH值。漆酶显示出非常好的热稳定性，在60℃下保持完全活性2小时。分离和测序编码M. Abomyces漆酶的基因。 M. Abomyces漆酶的开放阅读框的长度为623个氨基酸残基。铜结合残留物很好地保守，氨基酸序列对其他ascycete漆酶具有高同源性。有趣的是，分泌的漆酶从氨基和羧基末端加工。漆酶也与所有存在的四种涂布器结晶。
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