title: RNA helicase activity of Escherichia coli SecA protein.
abstract: SecA protein of Escherichia coli (E. coli), an ATPase essential for the translocation of precursor proteins, was found to have an additional activity of RNA helicase. This RNA unwinding activity of SecA was tested with two kinds of RNA duplex with different predicted stability. Each of these duplexes is consisted of two strands of unequal length with single-stranded ends. The RNA helicase activity of SecA required ATP and divalent cations. Confirmation of this activity came from the inhibition of unwinding of the RNA duplex when SecA was preincubated with its own polyclonal antibody. The biological significance of the RNA helicase activity of E. coli SecA protein is discussed.
authors.affiliation: Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Taejon. skpark@bioneer.kaist.ac.kr
authors.forename: S K
authors.initials: SK
authors.lastname: Park
authors.forename: D W
authors.initials: DW
authors.lastname: Kim
authors.forename: J
authors.initials: J
authors.lastname: Choe
authors.forename: H
authors.initials: H
authors.lastname: Kim
mesh_terms: D000251:Adenosine Triphosphatases / Q000302:isolation & purification / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D001426:Bacterial Proteins / Q000302:isolation & purification / Q000378:metabolism*; D001483:Base Sequence; D002413:Cations, Divalent / Q000378:metabolism; D002712:Chlorides / Q000494:pharmacology; D004926:Escherichia coli / Q000201:enzymology*; D029968:Escherichia coli Proteins; D007700:Kinetics; D017895:Manganese Compounds / Q000494:pharmacology; D026901:Membrane Transport Proteins; D009843:Oligoribonucleotides / Q000737:chemistry / Q000378:metabolism; D020365:RNA Helicases; D012316:RNA Nucleotidyltransferases / Q000302:isolation & purification / Q000378:metabolism*; D012330:RNA, Double-Stranded / Q000378:metabolism; D000069816:SEC Translocation Channels; D000081416:SecA Proteins; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D002413:Cations, Divalent; D002712:Chlorides; D029968:Escherichia coli Proteins; D017895:Manganese Compounds; D026901:Membrane Transport Proteins; D009843:Oligoribonucleotides; D012330:RNA, Double-Stranded; D000069816:SEC Translocation Channels; D000255:Adenosine Triphosphate; D012316:RNA Nucleotidyltransferases; D000251:Adenosine Triphosphatases; D020365:RNA Helicases; D000081416:SecA Proteins; C025340:manganese chloride