Biochemical and genetic characterization of a replication protein A dependent DNA helicase from the yeast, Saccharomyces cerevisiae.
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.
Department of Pediatrics, University of Maryland School of Medicine, Baltimore 21201.
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D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites; D002874:Chromosome Mapping; D004247:DNA / Q000494:pharmacology; D004265:DNA Helicases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004271:DNA, Fungal / Q000032:analysis; D004268:DNA-Binding Proteins / Q000494:pharmacology*; D005800:Genes, Fungal; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D051716:Replication Protein A; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins; D017421:Sequence Analysis
D004271:DNA, Fungal; D004268:DNA-Binding Proteins; D051716:Replication Protein A; D029701:Saccharomyces cerevisiae Proteins; D004247:DNA; D000251:Adenosine Triphosphatases; D004265:DNA Helicases; C091576:ECM32 protein, S cerevisiae