Bombyx mori Nucleopolyhedrovirus Encodes a DNA-Binding Protein Capable of Destabilizing Duplex DNA
Bombyx mori Nucleopolyhedrovirus Encodes a DNA-Binding Protein Capable of Destabilizing Duplex DNA
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家蚕核多角体病毒编码一种能够破坏双链 DNA 稳定性的 DNA 结合蛋白
作者：
V. Mikhailov;A. L. Mikhailova;Masashi Iwanaga;S. Gomi;S. Maeda
从感染B的家蚕细胞中纯化出一种表观分子量为38 kDa的DNA结合蛋白（命名为DBP）。桑核型多角体病毒（BmNPV）。用无色杆菌蛋白酶I消化分离的蛋白质后获得的六个肽部分或完全测序。氨基酸序列分析表明，DBP由位于BmNPV基因组（GenBank登录号L33180）第16189 - 17139位核苷酸的开放阅读框架（ORF 16）编码。该ORF（命名为dbp）是苜蓿银纹夜蛾多衣壳NPV ORF 25的同源物，其产物尚未鉴定。预测BmNPV DBP含有317个氨基酸（计算分子量为36.7 kDa），等电点为7.8。DBP在纯化过程中表现出多聚化的趋势，并被发现优先结合单链DNA。当与寡核苷酸结合时，DBP保护它们免受噬菌体T4 DNA聚合酶相关的3′→5′外切核酸酶的水解。受保护片段的大小表明DBP的结合位点大小为每个蛋白单体约30 nt。DBP，而不是BmNPV LEF-3，能够在体外系统中解旋部分DNA双链体。这种螺旋不稳定的能力与DBP在病毒复制中作为单链DNA结合蛋白的预测一致。
ABSTRACT A DNA-binding protein (designated DBP) with an apparent molecular mass of 38 kDa was purified to homogeneity from BmN cells (derived fromBombyx mori) infected with the B. morinucleopolyhedrovirus (BmNPV). Six peptides obtained after digestion of the isolated protein with Achromobacter protease I were partially or completely sequenced. The determined amino acid sequences indicated that DBP was encoded by an open reading frame (ORF16) located at nucleotides (nt) 16189 to 17139 in the BmNPV genome (GenBank accession no. L33180 ). This ORF (designated dbp) is a homolog of Autographa californica multicapsid NPV ORF25, whose product has not been identified. BmNPV DBP is predicted to contain 317 amino acids (calculated molecular mass of 36.7 kDa) and to have an isoelectric point of 7.8. DBP showed a tendency to multimerization in the course of purification and was found to bind preferentially to single-stranded DNA. When bound to oligonucleotides, DBP protected them from hydrolysis by phage T4 DNA polymerase-associated 3′→5′ exonuclease. The sizes of the protected fragments indicated that a binding site size for DBP is about 30 nt per protein monomer. DBP, but not BmNPV LEF-3, was capable of unwinding partial DNA duplexes in an in vitro system. This helix-destabilizing ability is consistent with the prediction that DBP functions as a single-stranded DNA binding protein in virus replication.
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DOI：
10.1073/pnas.91.23.11212
发表时间：
1994-11-08
影响因子：
11.1
作者：
KOOL, M;AHRENS, CH;VLAK, JM
通讯作者：
VLAK, JM
单纯疱疹病毒 1 的 DNA 聚合酶和单链 DNA 结合蛋白（感染细胞蛋白 8）之间的相互作用。
DOI：
--
发表时间：
1987
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
O'Donnell,ME;Elias,P;Funnell,BE;Lehman,IR
通讯作者：
Lehman,IR
影响因子：
5.6
作者：
SOENGAS, MS;GUTIERREZ, C;SALAS, M
通讯作者：
SALAS, M
影响因子：
3.7
作者：
AHRENS, CH;ROHRMANN, GF
通讯作者：
ROHRMANN, GF
影响因子：
56.9
作者：
PEARSON, M;BJORNSON, R;ROHRMANN, G
通讯作者：
ROHRMANN, G