The Bacterial Heterotrimeric Amidotransferase GatCAB: functions, structures and mechanism-based inhibitors
Main Article Content
Abstract
tRNA-dependent amidotransferases (AdT) are essential enzymes for protein biosynthesis in many bacteria and in all archaea. As AdT is essential for a number of pathogenic bacteria, and it is absent from mammalian cytoplasm, it is considered as a putative target for novel inhibitors that could be lead compounds to develop a new class of antibiotics. Besides GatFAB of Saccharomyces cerevisiae mitochondria and GatAB of Plasmodium falciparum apicoplast, all reported AdT can be divided into two groups: heterodimeric GatDE and heterotrimeric GatCAB. The latter is required to catalyze the conversion of Glu-tRNAGln and/or Asp-tRNAAsn into Gln-tRNAGln and/or Asn-tRNAAsn in many pathogenic bacteria. Recently determined high resolution crystal structures of several GatCAB could be used to design new inhibitors. In this review, we highlight the essential role of AdT for the faithful translation of glutamine and/or asparagine codons, we describe important features of the crystal structures of several GatCAB as well as tRNA/AdT/aaRS complexes for the formation of Gln-tRNAAsn and Asn-tRNAAsn, we finally summarize discoveries of AdT inhibitors based on their analogy to glutamine, adesosine tripoliphosphate and 3’-end of tRNA.
Article Details
Copyright (c) 2017 Pham VH, et al.

This work is licensed under a Creative Commons Attribution 4.0 International License.
Sheppard K, Akochy PM, Salazar JC, Söll D. The Helicobacter pylori amidotransferase GatCAB is equally efficient in glutamine-dependent transamidation of Asp-tRNAAsn and Glu-tRNAGln. J Biol Chem. 2007; 282: 11866-11873. Ref.: https://goo.gl/dfgopk
Chang KM, Hendrickson TL. Recognition of tRNAGln by Helicobacter pylori GluRS2--a tRNAGln-specific glutamyl-tRNA synthetase. Nucleic Acids Res. 2009; 37: 6942-6949. Ref.: https://goo.gl/vFSjrB
Wu J, Bu W, Sheppard K, Kitabatake M, Kwon ST, et al. Insights into tRNA-Dependent Amidotransferase Evolution and Catalysis from the Structure of the Aquifex aeolicus Enzyme. J Mol Biol. 2009; 391: 703-716. Ref.: https://goo.gl/0IEr7c
Curnow AW, Hong Kw, Yuan R, Kim Si, Martins O, et al. Glu-tRNAGln amidotransferase: a novel heterotrimeric enzyme required for correct decoding of glutamine codons during translation. Proc Natl Acad Sci U S A, 1997; 94: 11819-11826. Ref.: https://goo.gl/VtHKqn
Nakamura A, Sheppard K, Yamane J, Yao M, Söll D, et al. Two distinct regions in Staphylococcus aureus GatCAB guarantee accurate tRNA recognition. Nucleic Acids Res. 2010; 38: 672-682. Ref.: https://goo.gl/Oz1r7J
Nakamura A, Yao M, Chimnaronk S, Sakai N, Tanaka I. Ammonia Channel Couples Glutaminase with Transamidase Reactions in GatCAB. Science. 2006; 312: 1954-1958. Ref.: https://goo.gl/VTTBFo
Sheppard K, Yuan J, Hohn MJ, Jester B, Devine KM, et al. From one amino acid to another: tRNA-dependent amino acid biosynthesis. Nucleic Acids Res. 2008; 36: 1813-1825. Ref.: https://goo.gl/i0x0fN
Huot JL, Jacques Lapointe, Robert Chênevert, Marc Bailly, Daniel Kern. 5.14-Glutaminyl-tRNA and Asparaginyl-tRNA Biosynthetic Pathways. Elsevier. 2010; 383-431. Ref.: https://goo.gl/ZwhxGb
Araiso Y, Huot JL, Sekiguchi T, Frechin M, Fischer F, et al. Crystal structure of Saccharomyces cerevisiae mitochondrial GatFAB reveals a novel subunit assembly in tRNA-dependent amidotransferases. Nucleic Acids Res. 2014; 42: 6052-6063. Ref.: https://goo.gl/pZmBNq
Frechin M, Senger B, Brayé M, Kern D, Martin RP, et al. Yeast mitochondrial Gln-tRNA(Gln) is generated by a GatFAB-mediated transamidation pathway involving Arc1p-controlled subcellular sorting of cytosolic GluRS. Genes Dev. 2009; 23: 1119-1130. Ref.: https://goo.gl/QqkouY
Mailu BM, Arthur J, Nelson TM, Ramasamy G, Fritz-Wolf K, et al. Plasmodium Apicoplast Gln-tRNAGln Biosynthesis Utilizes a Unique GatAB Amidotransferase Essential for Erythrocytic Stage Parasites. J Biol Chem, 2015; 290: 29629-29641. Ref.: https://goo.gl/gaHBGQ
Shin S, Yun YS, Koo HM, Kim YS, Choi KY, et al. Characterization of a Novel Ser-cisSer-Lys Catalytic Triad in Comparison with the Classical Ser-His-Asp Triad. J Biol Chem. 2003; 278: 24937-24943. Ref.: https://goo.gl/lkXkIV
Deniziak M, Sauter C, Becker HD, Paulus CA, Giegé R, et al. Deinococcus glutaminyl-tRNA synthetase is a chimer between proteins from an ancient and the modern pathways of aminoacyl-tRNA formation. Nucleic Acids Res. 2007; 35: 1421-1431. Ref.: https://goo.gl/QHkb2F
Bailly M, Blaise M, Lorber B, Becker HD, Kern D. The transamidosome: a dynamic ribonucleoprotein particle dedicated to prokaryotic tRNA-dependent asparagine biosynthesis. Mol Cell. 2007; 28: 228-239. Ref.: https://goo.gl/yYxtDv
Silva GN, Fatma S, Floyd AM, Fischer F, Chuawong P, et al. A tRNA-independent mechanism for transamidosome assembly promotes aminoacyl-tRNA transamidation. J Biol Chem. 2013; 288: 3816-3822. Ref.: https://goo.gl/MTFWiy
Rampias T, Sheppard K, Soll D. The archaeal transamidosome for RNA-dependent glutamine biosynthesis. Nucleic Acids Res. 2010; 38: 5774-5783. Ref.: https://goo.gl/ed5tXy
Blaise M, Bailly M, Frechin M, Behrens MA, Fischer F, et al. Crystal structure of a transfer-ribonucleoprotein particle that promotes asparagine formation. EMBO J. 2010; 29: 3118-3129. Ref.: https://goo.gl/f5bUIx
Suzuki T, Yamashita K, Tanaka Y, Tanaka I, Yao M. Crystallization and preliminary X-ray crystallographic analysis of a bacterial Asn-transamidosome. Acta Crystallogr F Struct Biol Commun. 2014; 70: 790-793. Ref.: https://goo.gl/KzGbS9
Huot JL, Fischer F, Corbeil J, Madore E, Lorber B, et al. Gln-tRNAGln synthesis in a dynamic transamidosome from Helicobacter pylori, where GluRS2 hydrolyzes excess Glu-tRNAGln. Nucleic Acids Res. 2011; 39: 9306-9315. Ref.: https://goo.gl/w0Z72h
Suzuki T, Nakamura A, Kato K, Söll D, Tanaka I, et al. Structure of the Pseudomonas aeruginosa transamidosome reveals unique aspects of bacterial tRNA-dependent asparagine biosynthesis. Proc Natl Acad Sci U S A. 2015; 112: 382-387. Ref.: https://goo.gl/rtlp1N
Ito T, Yokoyama S. Two enzymes bound to one transfer RNA assume alternative conformations for consecutive reactions. Nature. 2010; 467: 612-616. Ref.: https://goo.gl/K9F8jz
Delarue M, Poterszman A, Nikonov S, Garber M, Moras D, et al. Crystal structure of a prokaryotic aspartyl tRNA-synthetase. EMBO J. 1994; 13: 3219-3229. Ref.: https://goo.gl/nMrB2j
Ruff M, Krishnaswamy S, Boeglin M, Poterszman A, Mitschler A, et al. Class II aminoacyl transfer RNA synthetases: crystal structure of yeast aspartyl-tRNA synthetase complexed with tRNA(Asp). Science. 1991; 252: 1682-1689. Ref.: https://goo.gl/cbVSUq
Fischer F, Huot JL, Lorber B, Diss G, Hendrickson TL, et al. The asparagine-transamidosome from Helicobacter pylori: a dual-kinetic mode in non-discriminating aspartyl-tRNA synthetase safeguards the genetic code. Nucleic Acids Res. 2012; 40: 4965-4976. Ref.: https://goo.gl/DqM04x
Decicco CP, Nelson DJ, Luo Y, Shen L, Horiuchi KY, et al. Glutamyl-γ-boronate Inhibitors of Bacterial Glu-tRNAGln Amidotransferase. Bioorg Med Chem Lett. 2001; 11: 2561-2564. Ref.: https://goo.gl/LsO5SH
Harpel MR, Horiuchi KY, Luo Y, Shen L, Jiang W, et al. Mutagenesis and mechanism-based inhibition of Streptococcus pyogenes Glu-tRNAGln amidotransferase implicate a serine-based glutaminase site. Biochemistry. 2002; 41: 6398-6407. Ref.: https://goo.gl/d60tIG
Horiuchi KY, Harpel MR, Shen L, Luo Y, Rogers KC, et al. Mechanistic studies of reaction coupling in Glu-tRNAGln amidotransferase. Biochemistry. 2001; 40: 6450-6457. Ref.: https://goo.gl/o5rygn
Moser J, Lorenz S, Hubschwerlen C, Rompf A, Jahn D. Methanopyrus kandleri glutamyl-tRNA reductase. J Biol Chem. 1999; 274: 30679-30685. Ref.: https://goo.gl/3Qr3zM
Huot JL, Balg C, Jahn D, Moser J, Emond A, et al. Mechanism of a GatCAB amidotransferase: aspartyl-tRNA synthetase increases its affinity for Asp-tRNA(Asn) and novel aminoacyl-tRNA analogues are competitive inhibitors. Biochemistry. 2007; 46: 13190-13198. Ref.: https://goo.gl/4TsUWh
Balg C, Huot JL, Lapointe J, Chenevert R. Inhibition of Helicobacter pylori aminoacyl-tRNA amidotransferase by puromycin analogues. J Am Chem Soc. 2008; 130: 3264-3265. Ref.: https://goo.gl/zBSNkv
Balg C, De Mieri M, Huot JL, Blais SP, Lapointe J, et al. Inhibition of Helicobacter pylori aminoacyl-tRNA amidotransferase by chloramphenicol analogs. Bioorg Med Chem. 2010; 18: 7868-7872. Ref.: https://goo.gl/Yy2Kd4
Schlunzen F, Zarivach R, Harms J, Bashan A, Tocilj A, et al. Structural basis for the interaction of antibiotics with the peptidyl transferase centre in eubacteria. Nature. 2001; 413: 814-821. Ref.: https://goo.gl/56Oe4A
Nissen P, Hansen J, Ban N, Moore PB, Steitz TA. The structural basis of ribosome activity in peptide bond synthesis. Science. 2000; 289: 920-930. Ref.: https://goo.gl/MSrl7m
Pham VH, Maaroufi H, Balg C, Blais SP, Messier N, et al. Inhibition of Helicobacter pylori Glu-tRNAGln amidotransferase by novel analogues of the putative transamidation intermediate. FEBS Lett. 2016; 590: 3335-3345. Ref.: https://goo.gl/N6HIkv
Klinchan C, Yu-Ling H, Chiang LL, Pluempanupat W, Chuawong P. Synthesis of non-hydrolyzable substrate analogs for Asp-tRNAAsn/Glu-tRNAGln amidotransferase. Tetrahedron Letters. 2014; 55: 6204-6207. Ref.: https://goo.gl/j5Gn5W
Pham VH, Maaroufi H, Levesque RC, Lapointe J. Cyclic peptides identified by phage display are competitive inhibitors of the tRNA-dependent amidotransferase of Helicobacter pylori. Peptides. 2016; 79: 8-15. Ref.: https://goo.gl/1Oej07
Söll D, Schimmel PR. 15.Aminoacyl-tRNA Synthetases. The Enzymes. 1974; 489-538. Ref.: https://goo.gl/mY4Bj9
Nissen P, Thirup S, Kjeldgaard M, Nyborg J. The crystal structure of Cys-tRNACys-EF-Tu-GDPNP reveals general and specific features in the ternary complex and in tRNA. Structure. 1999; 7: 143-156. Ref.: https://goo.gl/0NwJ0J
Stepanov VG, Nyborg J. Thermal stability of aminoacyl-tRNAs in aqueous solutions. Extremophiles. 2002; 6: 485-490. Ref.: https://goo.gl/JquM6u