ENDONUCLEASE (R)-SUBUNITS OF TYPE-I AND TYPE-III RESTRICTION-MODIFICATION ENZYMES CONTAIN A HELICASE-LIKE DOMAIN
ENDONUCLEASE (R)-SUBUNITS OF TYPE-I AND TYPE-III RESTRICTION-MODIFICATION ENZYMES CONTAIN A HELICASE-LIKE DOMAIN
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DOI：
10.1016/0014-5793(91)81301-n
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发表时间：
1991-10-21
期刊：
影响因子：
3.5
通讯作者：
KOONIN, EV
中科院分区：
文献类型：
--
作者：
GORBALENYA, AE;KOONIN, EV
在EcoK限制修饰（R-M）酶的内切核酸酶（R）亚基与所谓的“DEAD”家族的RNA和DNA解旋酶之间证明了统计学上显著的氨基酸序列相似性。进一步表明，I型和III型R-M酶的R亚基的所有三个已知序列含有先前描述的解旋酶超家族II典型的保守氨基酸序列基序[（1989）Nucleic Acids Res.17，4713-4730]。提出了一个假设，这些酶可能发挥解旋酶活性可能需要在切割位点的DNA的本地解旋。
A statistically significant amino acid sequence similarity is demonstrated between the endonuclease (R) subunit of EcoK restriction-modification (R-M) enzyme, and RNA and DNA helicases of the so-called 'DEAD' family. It is further shown that all three known sequences of R subunits of type-I and type-III R-M enzymes contain the conserved amino acid sequence motifs typical of the previously described helicase superfamily II [(1989) Nucleic Acids Res. 17, 4713-4730]. A hypothesis is proposed that these enzymes may exert helicase activity possibly required for local unwinding of DNA in the cleavage sites.