中文摘要：

目前，蛋白质可溶性和热稳定性已成为重组蛋白高效生产、功能应用和长久保存不可回避的问题，而使用酸性蛋白融合标签可能是其有效解决策略。酰基载体蛋白（ACP）是脂肪酸生物合成途径的必要组分，在大肠杆菌中为一个高度酸性的小分子多肽。将大肠杆菌ACP与几个热不稳定的靶蛋白[如小桐子抗坏血酸过氧化物酶1（JcAPXl）、大豆核酮糖-1，5-二磷酸羧化／加氧酶的活化酶2（GmRCA2）、大肠杆菌高丝氨酸D．转琥珀酰酶（EcMetA）]进行基因融合并使其在大肠杆菌中诱导表达，发现ACP融合能显著增强这些重组靶蛋白的可溶性。另外，对重组蛋白的热处理和酶活性分析发现，融合ACP还能极大提高这三个靶蛋白的热稳定性，并有效保护JcAPXl酶活免遭热失活，使其耐热性提高了至少2℃。ACP的这种效果推测可能与其高酸度特性有关，可以作为一个新的功能酸性融合标签。

英文摘要：

At present, protein solubility and thermostability has become an unavoidable problem for the efficient production, functional application and long-term preservation of the recombinant proteins. Regarding this, the strategy by using acidic protein fusion tags appears to be an effectual solution. Acyl cartier protein （ACP）, an essential component of fatty acid biosynthesis pathway, is a small and highly acidic peptide in Escherichia coll. It was in-frame fused with several heat-labile target proteins [ e. g. the ascorbate peroxidase 1 of Jatropha curcas （JcAPX1）, the activase isoform 2 of ribulose-1,5-bisphosphate carboxylase/oxygenase of soybean （GmRCA2）, the homoserine O-transsuccinylase of E. coli （EcMetA） ] at the gene level for inducible expression in E. coll. ACP fusion could significantly enhance the solubility and thermostability of all these recombinant target proteins, and also effectively protect enzyme JcAPX1 from heat inactivation, with increased heat tolerance of at least 2℃. Presumably, this effect of ACP might be related to its high acidity, and it could be used as a novel functional acidic fusion tag in future studies.