Cloning and characterization of the RNase P RNA genes from two porcine mycoplasmas.
We report the cloning of the RNase P RNA genes from the primary aetiological agent of porcine pneumonia, Mycoplasma hyopneumoniae, and the closely related commensal, Mycoplasma flocculare. The monocistronic genes each have promoters with AT-rich -35 regions and Rho-independent-like transcription terminators which are retained in the RNase P RNA. Both of these RNase P RNA variants are shown to be catalytically active in vitro in spite of a low overall GC content (30%). Our results suggest a new example of a stable mini-helix in the conserved core of the mycoplasmal RNase P RNAs. Deletion of the corresponding structural element in Escherichia coli RNase P RNA (M1 RNA) generated an RNase P RNA with an impaired substrate interaction. Displacement of this structural element with the mycoplasmal mini-helix resulted in an enzyme with a phenotype similar to that of wild-type M1 RNA. In addition, this structural element is important for lead ion-induced cleavage at specific sites in M1 RNA.
Svärd
S G
SG
Department of Microbiology, University of Uppsala, Sweden.
Mattsson
J G
JG
Johansson
K E
KE
Kirsebom
L A
LA
D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D004722:Endoribonucleases / Q000235:genetics*; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial; D007854:Lead / Q000494:pharmacology; D008969:Molecular Sequence Data; D009174:Mycoplasma / Q000145:classification / Q000201:enzymology / Q000235:genetics* / Q000302:isolation & purification; D009690:Nucleic Acid Conformation; D045729:Pneumonia of Swine, Mycoplasmal / Q000382:microbiology / Q000662:veterinary; D011401:Promoter Regions, Genetic; D012322:RNA Precursors / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional / Q000187:drug effects; D012329:RNA, Bacterial / Q000378:metabolism; D016337:RNA, Catalytic / Q000235:genetics*; D043262:Ribonuclease P; D013045:Species Specificity; D013552:Swine; D013553:Swine Diseases / Q000382:microbiology
D029968:Escherichia coli Proteins; D012322:RNA Precursors; D012329:RNA, Bacterial; D016337:RNA, Catalytic; D007854:Lead; D004722:Endoribonucleases; D043262:Ribonuclease P; C470865:ribonuclease P, E coli