中文摘要：

新奇 thermophilic 内葡聚醣(EGt ) 从 mesophilicfungus (镰刀霉 oxysporum LI9 ) 被提取。我们作为底层用 carboxymethyl (CMC-Na ) 的钠盐调用了常规运动的酶反应。EGt 在保留的 75 deg Cwhen 显示了最佳的活动在 30-85deg C 的温度范围运用 30 min。热稳定性曲线测量 at70 deg C 建议它的半衰期时间是 15.1 min。这项活动面对 Co~(2+) 或 Mg~(2+) 被提高，但是由 Pb~(2+) 和 Fe~(3+) 禁止了。而且， N-bromosuccinimide (NBS ) 修正导致了 EGt 活动的完全的损失，建议色氨酸残余可以涉及酶活性部位。弹药酸作文分析证明 EGt 包含更多的脯氨酸残余。EGt 向 p-nitro-phenyl 纤维二醣(pNPC ) 缺乏活动。EGt 的 N-terminalamino 酸顺序是 SYRVPAANGFPNPDASQEKQ，并且 EGt 的基因被定序并且分析。广泛的顺序排列没能证明在 EGt 和任何已知的 endoglucanases.This 之间的任何相同是从 themesophilic 真菌 F 探讨可加水分解纤维素的酶的热改编的第一份报告。oxysporum。也许，在一个有机体的多重同功的表示帮助它适应复杂生活环境。

英文摘要：

A novel thermophilic endoglucanase （EGt） was extracted from a mesophilic fungus （Fusarium oxysporum L19）. We invoked conventional kinetic enzyme reactions using the sodium salt of carboxymethyl cellulose （CMC-Na） as substrate. EGt displayed optimal activity at 75℃ when kept running 30 min in the temperature range of 30-85℃. Thermal stability curve measured at 70℃ suggested that its half-life time is 15.1 min. The activity was enhanced in the presence of Co^2＋ or Mg^2＋ but inhibited by Pbo^2＋ and Fe^3＋. Moreover, N-bromosuccinimide （NBS） modification resulted in a complete loss of EGt activity, suggesting that tryptophan residues may be involved in the enzyme active site. Amino acid composition analysis demonstrated that EGt contains more proline residues. EGt lacks activity towards p-nitrophenyl cellobiose （pNPC）. The N-terminal amino acid sequence of EGt is SYRVPAANGFPNPDASQEKQ, and the gene of EGt was sequenced and analyzed. Extensive sequence alignments failed to show any homology between EGt and any known endoglucanases. This is the first report addressing the thermal adaptation of a cellulolytic enzyme from the mesophilic fungus F. oxysporum. Maybe the expression of multiple isoenzyme in an organism helps it adapt to complex living environments.