Cloning and characterization of two novel DNases from Streptococcus pyogenes
Cloning and characterization of two novel DNases from Streptococcus pyogenes
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DOI：
10.1007/s00203-002-0412-8
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发表时间：
2002-06-01
影响因子：
2.8
通讯作者：
Ohta, M
中科院分区：
文献类型：
--
作者：
Hasegawa, T;Torii, K;Ohta, M
应用双向凝胶电泳技术对M1型化脓链球菌培养上清中的蛋白质（外蛋白）进行分离，并测定其N端氨基酸序列。将氨基酸序列与S.化脓菌基因组数据库。其编码序列与mj 2-v（mf 2变体）和mf 3两个基因的序列相似，mj 2-v和mf 3基因与编码有丝分裂因子（MF）的基因序列相似，MF具有DNA酶活性。重组基因在大肠杆菌中表达并合成蛋白。Mf 2-v和Mf 3具有DNA酶活性。Mf 2-v的活性定位于蛋白质的C-末端的一半。mf 3基因存在于大多数临床分离的S.在20%的分离株中检测到MF 2基因。临床分离的S.因此显示化脓性链球菌菌株是DNA酶。
The proteins in the culture supernatant (exoproteins) from Streptococcus pyogenes serotype M 1 were separated by two-dimensional gel electrophoresis, and their N-terminal amino acid sequences were determined. The amino acid sequences were compared to sequences in the S. pyogenes genome database. The coding sequence showed similarity to sequences of two genes, mj2-v (mf2 variant) and mf3, which had sequence similarity to genes encoding mitogenic factor (MF); MF has DNase activity. The recombinant genes were expressed in Escherichia coli and the proteins were synthesized. Mf2-v and Mf3 had DNase activity. The activity of Mf2-v was localized to the C-terminal half of the protein. The mf3 gene was shown to be present in most clinically isolated strains of S. pyogenes tested, and the mf2 gene was detected in 20% of the isolates. The products of the mf2 and mf3 genes in clinically isolated S. pyogenes strains were thus shown to be DNases.