B.Sc. Imperial College London, 1986
Ph.D. Univ. of Manchester, 1990
Postdocs. Novartis, ETH Zürich, Yale Univ., 1990-1997
Research Associate Professor, Copenhagen Univ., 1998-2001
Our research is directed towards understanding the mechanisms that determine how cells ensure the accurate translation of the genetic code, and how changes in the underlying processes impact cellular health and contribute to microbial pathogenesis and disease. Many of these processes are essential and unique to particular systems, making them ideal potential drug targets.
Quality control in protein synthesis
Ribosomes are the protein synthesis factories of the cell that translate the codons of mRNA into amino acids. Protein synthesis proceeds by delivery to the ribosome of aminoacyl-tRNAs, which pair with the corresponding mRNA sequences. Aminoacyl-tRNAs are made by the aminoacyl-tRNA synthetases, a family of twenty proteins each of which pairs a particular amino acid with the correct tRNA. Accurate aminoacyl-tRNA synthesis often requires an additional editing activity intrinsic to many aaRSs. The editing activity significantly decreases the level of mistakes in aminoacyl-tRNA synthesis in vitro and in vivo, although quantitative analysis of its contribution to the overall fidelity of translation has not been performed. The overall aim of our work is to develop experimental systems to quantitatively measure the frequency of aaRS-dependent misincorporation for several amino acids and evaluate the contribution of aaRS editing to overall translational fidelity in vivo.
Translational control of antibiotic resistance
In responses to different environmental stresses, such as the presence of antibiotics, microbes direct resources away from translation to a variety of pathways that contribute to resistance. Elongation factor P (EF-P). EF-P is a protein that mimics the structure and function of a tRNA and binds ribosomes. Aminoacylation of EF-P is required for optimal growth under a variety of conditions, for example at key points during Salmonella infection. We are interested in understanding how EF-P mimics tRNA at the molecular level and how this provides a novel mechanism for the post-transcriptional control of gene expression.
- Hersch SJ, Wang M, Zou SB, Rajkovic A, Moon K.-M, Foster, LJ, Ibba M & Navarre WW (2013) Divergent protein motifs direct EF-P mediated translational regulation in Salmonella and Escherichia coli. mBio 4, e00180-13.
- Bullwinkle TJ & Ibba M (2013) Emergence and Evolution. Top. Curr. Chem. In Press.
- Bullwinkle TJ, Zou SB, Rajkovic A, Hersch SJ, Elgamal S, Robinson N, Smil D, Bolshan Y, Navarre WW & Ibba M (2013) (R)-β-lysine modified elongation factor P functions in translation elongation. J. Biol. Chem. 288, 4416-4423.
- Yadavalli SS & Ibba M (2013) Selection of tRNA charging quality control mechanisms that increase mistranslation of the genetic code. Nucleic Acids Res. 41, 1104-1112.
- Raina M & Ibba M (2012) Taking AIM at the start of translation. J. Mol. Biol. 423, 473-474.
- Elo, JM, Yadavalli SS, Euro L, Isohanni P, Götz A, Carroll C, Valanne L, Alkuraya FS, Uusimaa J, Paetau A, Caruso EM, Pihko H, Ibba M, Tyynismaa H & Suomalainen A (2012) Mitochondrial phenylalanyl-tRNA synthetase mutations underlie fatal infantile Alpers encephalopathy. Hum. Mol. Genet. 21, 4521-4529.
- Rogers TE, Ataide SF, Dare K, Katz A, Seveau S, Roy H & Ibba M (2012) A pseudo-tRNA modulates antibiotic resistance in Bacillus cereus. PLoS ONE 7, e41248.
- Raina M, Elgamal S, Santangelo TJ & Ibba M (2012 ) Association of a multi-synthetase complex with translating ribosomes in the archaeon Thermococcus kodakarensis. FEBS Lett. . 586, 2232-2238.
- Greber BJ, Boehringer D, Godinic-Mikulcic V, Crnkovic A, Ibba M, Weygand-Durasevic I & Ban N (2012) Cryo-EM Structure of the Archaeal 50S Ribosomal Subunit in Complex with Initiation Factor 6 and Implications for Ribosome Evolution. J. Mol. Biol. 418, 145-160.
- Dare K & Ibba M (2012) Roles of tRNA in cell wall biosynthesis. Wiley Interdiscip. Rev. RNA. 3, 247-264.
- Yadavalli SS & Ibba M (2012) Quality control in aminoacyl-tRNA synthesis: its role in translational fidelity. Adv. Protein Chem. Struct. Biol. 86, 1-43.
- Zou SB, Hersch S, Roy H, Wiggers JB, Leung A, Buranyi S, Xie JL, Dare K, Ibba M & Navarre WW (2012) Loss of Elongation factor P Disrupts Bacterial Outer-membrane Integrity. J. Bacteriol. 194, 413-425.
- Roy H, Zou SB, Bullwinkle TJ, Wolfe BS, Gilreath MS, Forsyth CJ, Navarre WW & Ibba M (2011) The tRNA synthetase paralog PoxA modifies elongation factor-P with (R)-β-lysine. Nat. Chem. Biol. 7, 667-669. Nature Research Highlight. OSU news.
- Gilreath MS, Roy H, Bullwinkle TJ, Katz A, Navarre WW & Ibba M (2011) Beta-lysine discrimination by lysyl-tRNA synthetase. FEBS Letters. 585, 3284-3288.
- Banerjee R, Reynolds NM, Yadavalli SS, Rice C, Roy H, Banerjee P, Alexander RW & Ibba M. (2011) Mitochondrial aminoacyl-tRNA synthetase single nucleotide polymorphisms that lead to defects in refolding but not aminoacylation. J. Mol. Biol. 410, 280-293.
- Zou SB, Roy H, Ibba M & Navarre WW. (2011) Elongation factor P mediates a novel post-transcriptional regulatory pathway critical for bacterial virulence. Virulence 2, 1-5.
- Godinic-Mikulcic V, Jaric J, Hausmann CD, Ibba M & Weygand-Durasevic I. (2011) An archaeal tRNA-synthetase complex that enhances aminoacylation under extreme conditions. J. Biol. Chem. 286, 3396-3404.
OTHER RELEVANT PUBLICATIONS
- Reynolds NM, Lazazzera BA & Ibba M. (2010) Cellular mechanisms that control mistranslation. Nat Rev Microbiol 8, 849-856.
- Weygand-Durasevic I & Ibba M. (2010) New roles for codon usage. Science 329, 1473-1474.
- Roy H & Ibba M. (2010) Bridging the gap between ribosomal and non-ribosomal protein synthesis. Proc Natl Acad Sci USA 107, 14517-14518.
- Navarre WW, Zou S, Roy H, Xie JL, Savchenko A, Singer A, Evdokimova E, Prost LR, Kumar R, Ibba M & Fang FC. (2010) PoxA, YjeK and elongation factor P coordinately modulate virulence and drug resistance in Salmonella enterica. Mol Cell 39, 209-221.
- Reynolds NM, Ling J, Roy H, Banerjee R, Repasky SE, Hamel P & Ibba M. (2010) Cell-specific differences in the requirements for translational quality control. Proc Natl Acad Sci USA 107, 4063-4068..
- Ling J, So BR, Yadavalli SS, Roy H, Shoji S, Fredrick K, Musier-Forsyth K & Ibba M. (2009) Resampling and editing of mischarged tRNA prior to translation elongation. Mol Cell 33, 654-660.
- Roy H & Ibba M. (2008) RNA-dependent lipid remodeling by bacterial multiple peptide resistance factors. Proc Natl Acad Sci USA 105, 4667-4672.
- Ling J, Roy H, Qin D, Rubio MA, Alfonzo JD, Fredrick K & Ibba M. (2007) Pathogenic mechanism of a human mitochondrial tRNAPhe mutation associated with MERRF syndrome. Proc Natl Acad Sci USA 104, 15299-15304.
- Ling J, Roy H & Ibba M. (2007) Mechanism of tRNA-dependent editing in translational quality control. Proc Natl Acad Sci USA 104, 72-77.
- Sauerwald A, Zhu W, Major TA, Roy H, Palioura S, Jahn D, Whitman W, Yates JR 3rd, Ibba M & Söll D. (2005) RNA-dependent cysteine biosynthesis in archaea. Science 307, 1969-1972.
- Roy H, Ling J, Irnov and Ibba M. (2004) Post-transfer editing in vitro and in vivo by the beta-subunit of phenylalanyl-tRNA synthetase. EMBO J. 23, 4639-4648.
- Jester B, Levengood J, Roy H, Ibba M & Devine K. (2003) Non-orthologous replacement of lysyl-tRNA synthetase prevents addition of lysine analogs to the genetic code. Proc Natl Acad Sci USA 100, 14351-14356.