BACTERIOPHAGE T7 DEOXYRIBONUCLEIC-ACID REPLICATION INVITRO .7. ESCHERICHIA-COLI THIOREDOXIN - SUBUNIT OF BACTERIOPHAGE T7-DNA POLYMERASE
BACTERIOPHAGE T7 DEOXYRIBONUCLEIC-ACID REPLICATION INVITRO .7. ESCHERICHIA-COLI THIOREDOXIN - SUBUNIT OF BACTERIOPHAGE T7-DNA POLYMERASE
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DOI：
10.1073/pnas.73.3.780
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发表时间：
1976-01-01
影响因子：
11.1
通讯作者：
RICHARDSON, CC
中科院分区：
文献类型：
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作者：
MARK, DF;RICHARDSON, CC
T7 DNA聚合酶（DNA核苷酸转移酶;脱氧核苷三磷酸：DNA脱氧核苷酸转移酶，EC 2.7.7.7）由噬菌体基因5所指定的84，000道尔顿蛋白质和大肠杆菌tsnC基因所指定的12，000道尔顿蛋白质（TsnC蛋白质）组成。杆菌这两种蛋白质都是T7 DNA聚合酶活性和T7 DNA复制所必需的。TsnC蛋白与大肠杆菌的硫氧还蛋白相同。通过以下标准鉴定两种蛋白质在大肠杆菌中的活性：两种蛋白质的均质制备物具有TsnC和硫氧还蛋白活性;两种蛋白质显示出相似的热稳定性;它们在含有十二烷基硫酸钠的聚丙烯酰胺凝胶上具有相同的迁移率，对应于12，000的分子量;它们的氨基酸组成不可区分;针对硫氧还蛋白制备的抗体抑制TsnC活性;从纯化的T7 DNA聚合酶中分离的TsnC蛋白具有硫氧还蛋白活性。T7 DNA聚合酶本身的制剂表现出硫氧还蛋白的活性，并被硫氧还蛋白抗体部分抑制。
T7 DNA polymerase (DNA nucleotidyltransferase; deoxynucleosidetriphosphate:DNA deoxynucleotidyltransferase, EC 2.7.7.7) is composed of an 84,000 dalton protein specified by the gene 5 of the phage and a 12,000 dalton protein (TsnC protein) specified by the tsnC gene of E. coli. Both proteins are necessary for T7 DNA polymerase activity and for the replication of T7 DNA. The TsnC protein is identical to thioredoxin of E. coli by the following criteria: homogeneous preparations of both proteins have TsnC and thioredoxin activity; both proteins show similar stability to heat; they have identical mobilities, corresponding to a molecular weight of 12,000, on polyacrylamide gels containing sodium dodecyl sulfate; their amino acid compositions are indistinguishable; antibody prepared against thioredoxin inhibits TsnC activity; and TsnC protein isolated from purified T7 DNA polymerase has thioredoxin activity. Preparations of T7 DNA polymerase itself exhibit thioredoxin activity and are partially inhibited by antibody to thioredoxin.