Aminoglycoside Resistance Genes SGM and kgmB Protect Bacterial but Not Yeast Small Ribosomal Subunits in Vitro Despite High Conservation of the rRNA A-site

Res Microbiol. Nov-Dec 2008;159(9-10):658-62. doi: 10.1016/j.resmic.2008.09.006. Epub 2008 Oct 1.

Abstract

The aminoglycoside resistance genes sgm from Micromonospora zionensis and kgmB from Streptomyces tenebrarius were cloned into a yeast expression vector to test whether the encoded prokaryotic methylases can modify the 18S rRNA A-site and thus confer resistance to G-418. Despite the detectable presence of mRNAs in yeast cells, neither G-418-resistant yeast transformants nor positive western blot signals were obtained. Neither methylase was capable of methylating 40S subunits despite very high conservation of the antibiotic rRNA binding sites. However, the results provide novel insight into the action of Sgm by showing that it methylates the same site as KgmB, i.e. G1405 in 16S rRNA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aminoglycosides / pharmacology*
  • Binding Sites
  • Cloning, Molecular
  • Drug Resistance, Bacterial / genetics*
  • Escherichia coli / drug effects
  • Escherichia coli / enzymology
  • Escherichia coli / genetics
  • Gentamicins / pharmacology*
  • Methyltransferases / genetics
  • Methyltransferases / metabolism*
  • RNA, Bacterial / chemistry
  • RNA, Bacterial / genetics
  • RNA, Bacterial / metabolism*
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • RNA, Ribosomal, 16S / chemistry
  • RNA, Ribosomal, 16S / genetics
  • RNA, Ribosomal, 16S / metabolism*
  • RNA, Ribosomal, 18S / chemistry
  • RNA, Ribosomal, 18S / genetics
  • RNA, Ribosomal, 18S / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Ribosomes / metabolism
  • Saccharomyces cerevisiae / drug effects
  • Saccharomyces cerevisiae / enzymology
  • Saccharomyces cerevisiae / genetics

Substances

  • Aminoglycosides
  • Gentamicins
  • RNA, Bacterial
  • RNA, Messenger
  • RNA, Ribosomal, 16S
  • RNA, Ribosomal, 18S
  • antibiotic G 418
  • Methyltransferases
  • rRNA (adenosine-O-2'-)methyltransferase