Biswas E E, Chen P H, Leszyk J, Biswas S B
Department of Pediatrics, University of Maryland School of Medicine, Baltimore 21201.
Biochem Biophys Res Commun. 1995 Jan 26;206(3):850-6. doi: 10.1006/bbrc.1995.1121.
We have purified a DNA dependent ATPase/DNA helicase, DNA helicase B, from S. cerevisiae. Helicase B was a 129-kDa polypeptide. The ATPase activity of helicase B was strongly DNA dependent. The DNA helicase activity was stimulated by yeast replication protein A, indicating a probable function in DNA replication. Helicase B showed a 5'-->3' polarity of movement. Protein sequencing indicated that helicase B was identical to a hypothetical 127-kDa polypeptide encoded by yORF61, located 5' upstream of the BMH1 locus in chromosome V. The protein sequence contained a "type I ATP/GTP binding motif" and other helicase-like motifs and the expressed protein exhibited helicase activity. Thus, we concluded that yORF61 is the gene for helicase B and will be referred to as HCSB.
我们从酿酒酵母中纯化出了一种依赖DNA的ATP酶/DNA解旋酶——DNA解旋酶B。解旋酶B是一种129千道尔顿的多肽。解旋酶B的ATP酶活性强烈依赖于DNA。酵母复制蛋白A刺激了DNA解旋酶活性，这表明它在DNA复制中可能具有某种功能。解旋酶B表现出5'→3'的移动极性。蛋白质测序表明，解旋酶B与由yORF61编码的一种假设的127千道尔顿多肽相同，yORF61位于第五条染色体上BMH1基因座上游5'处。该蛋白质序列包含一个“Ⅰ型ATP/GTP结合基序”和其他类似解旋酶的基序，并且表达的蛋白质表现出解旋酶活性。因此，我们得出结论，yORF61是解旋酶B的基因，将其称为HCSB。
