title: Staphylococcus aureus MazF specifically cleaves a pentad sequence, UACAU, which is unusually abundant in the mRNA for pathogenic adhesive factor SraP.
abstract: Escherichia coli mRNA interferases, such as MazF and ChpBK, are sequence-specific endoribonucleases encoded by toxin-antitoxin (TA) systems present in its genome. A MazF homologue in Staphylococcus aureus (MazF(Sa)) has been shown to inhibit cell growth when induced in E. coli. Here, we determined the cleavage site for MazF(Sa) with the use of phage MS2 RNA as a substrate and CspA, an RNA chaperone, which prevents the formation of secondary structures in the RNA substrate. MazF(Sa) specifically cleaves the RNA at a pentad sequence, U downward arrow ACAU. Bioinformatics analysis revealed that this pentad sequence is significantly abundant in several genes, including the sraP gene in the S. aureus N315 strain. This gene encodes a serine-rich protein, which is known to play an important role in adhesion of the pathogen to human tissues and thus in endovascular infection. We demonstrated that the sraP mRNA became extremely unstable in comparison with the ompA mRNA only when MazF(Sa) was induced in E. coli. Further bioinformatics analysis indicated that the pentad sequence is also significantly abundant in the mRNAs for all the pathogenic factors in S. aureus. This observation suggests a possible regulatory relationship between the MazEF(Sa) TA module and the pathogenicity in S. aureus.
authors.affiliation: Department of Biochemistry, Robert Wood Johnson Medical School, 675 Hoes Lane, Piscataway, NJ 08854, USA.
authors.forename: Ling
authors.initials: L
authors.lastname: Zhu
authors.forename: Koichi
authors.initials: K
authors.lastname: Inoue
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yoshizumi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kobayashi
authors.forename: Yonglong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Ming
authors.initials: M
authors.lastname: Ouyang
authors.forename: Fuminori
authors.initials: F
authors.lastname: Kato
authors.forename: Motoyuki
authors.initials: M
authors.lastname: Sugai
authors.forename: Masayori
authors.initials: M
authors.lastname: Inouye
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D001665:Binding Sites; D019295:Computational Biology; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D008969:Molecular Sequence Data; D020871:RNA Stability; D012333:RNA, Messenger / Q000737:chemistry* / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013211:Staphylococcus aureus / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity
chemical_list: D001426:Bacterial Proteins; D012333:RNA, Messenger