N-Terminal 112 amino acid residues are not required for the sialyltransferase activity of Photobacterium damsela α2,6-sialyltransferase
N-Terminal 112 amino acid residues are not required for the sialyltransferase activity of Photobacterium damsela α2,6-sialyltransferase
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DOI：
10.1007/s10529-007-9588-y
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发表时间：
2008-04-01
影响因子：
2.7
通讯作者：
Chen, Xi
中科院分区：
文献类型：
--
作者：
Sun, Mingchi;Li, Yanhong;Chen, Xi
将发光杆菌 damsela α 2,6-唾液酸转移酶克隆为具有不同长度（16-497 个氨基酸或 113-497 个氨基酸）的 N-和 C-His 标记融合蛋白。表达和活性测定表明，该蛋白的 N 端 112 个氨基酸残基并不是其 α2,6-唾液酸转移酶活性所必需的。在测试的四种截短形式中，含有16-497个氨基酸残基的N-His标记的Delta 15Pd2,6ST(N)具有最高的表达水平。与 Delta 15Pd2,6ST(N) 类似，较短的 Delta 112Pd2,6ST(N) 在 7.5-10.0 的宽 pH 范围内具有活性。唾液酸转移酶活性不需要二价金属离子，并且EDTA和二硫苏糖醇的添加不会显着影响活性。
Photobacterium damsela alpha 2,6-sialyltransferase was cloned as N- and C- His-tagged fusion proteins with different lengths (16-497 aa or 113-497 aa). Expression and activity assays indicated that the N-terminal 112 amino acid residues of the protein were not required for its alpha 2,6-sialyltransferase activity. Among four truncated forms tested, N-His-tagged Delta 15Pd2,6ST(N) containing 16-497 amino acid residues had the highest expression level. Similar to the Delta 15Pd2,6ST(N), the shorter Delta 112Pd2,6ST(N) was active in a wide pH range of 7.5-10.0. A divalent metal ion was not required for the sialyltransferase activity, and the addition of EDTA and dithiothreitol did not affect the activity significantly.