Archaeosine

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Structural formula
Structural formula of archaeosin
General
Surname Archaeosine
other names
  • G * (short code)
  • 2-Amino-7-β- D- ribofuranosyl-4-oxo-1 H -pyrrolo [2,3- d ] pyrimidine-5-carboximidamide
  • 2-Amino-7 - [(2 R , 3 R , 4 S , 5 R ) -3,4-dihydroxy-5- (hydroxymethyl) oxolan-2-yl] -4-oxo-1 H -pyrrolo [2, 3- d ] pyrimidine-5-carboximidamide
Molecular formula C 12 H 16 N 6 O 5
External identifiers / databases
CAS number 148608-52-0
PubChem 132841
ChemSpider 117239
Wikidata Q632302
properties
Molar mass 324.29 g mol −1
Physical state

firmly

safety instructions
GHS hazard labeling
no classification available
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Archaeosin (G * ) is a rare nucleoside and occurs in the tRNA . It consists of β- D- ribofuranose (sugar) and a base, which has the same base pairing properties as guanine . Like queuosine, it is structurally derived from guanosine . The N 7 atom of guanine is replaced by a C 7 atom and thus forms 7-deazaguanosine , to which further substituents can be added.

Archaeosin was first discovered by Kilpatrick and Walker in 1982 when sequencing tRNA from Thermoplasma acidophilum . It was later shown to be found in many archaeal species. It is found in the dihydrouracil loop at position 15 in tRNAs. The change occurs through an exchange reaction using tRNA-guanine transglycosylase (TGT). The enzyme inserts - instead of the original guanine - the 7-cyano-7-deazaguanine (preQ 0 base) in vitro at position 15 without the phosphate-ribose chain being broken at this position. Since the archaeosin base and 7-aminomethyl-7-deazaguanine (preQ 1 base) are not incorporated into the tRNA by this enzyme, preQ 0 appears to be the actual substrate for TGT. It is therefore a key enzyme for this biosynthetic pathway to archaeosin in archaeal tRNAs.

literature

  • Florian Klepper: Synthesis of the natural tRNA nucleoside modifications queuosine and archaeosine , dissertation, Munich 2007 ( PDF ; 5.1 MB).

Individual evidence

  1. ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
  2. ↑ Patrick A. Limbach, Pamela F. Crain, James A. McCloskey: "Summary: the modified nucleosides of RNA", Nucleic Acids Research , 1994 , 22  (12), pp. 2183-2196 ( doi : 10.1093 / nar / 22.12 .2183 , PMC 523672 (free full text), PMID 7518580 ).
  3. ↑ MW Kilpatrick, RT Walker: “The nucleotide sequence of the tRNA M Met from the archaebacterium Thermoplasma acidophilum”, Nucleic Acids Research , 1981 Sep 11, 9  (17), pp. 4387-4390 ( PMC 327441 (free full text); PMID 6913864 ).
  4. ↑ MW Kilpatrick, RT Walker: "The nucleotide sequence of the tRNA M Met from the archaebacterium Thermoplasma acidophilum", Central Journal for Bacteriology, Microbiology and Hygiene , Section 1, Originals C: Allgemeine, Angewandte und Oekologische Mikrobiologie , 1982 , 3  (1 ), Pp. 79-89.
  5. ↑ CG Edmonds, PF Crain, R. Gupta, T. Hashizume, CH Hocart, JA Kowalak, SC Pomerantz, KO Stetter, JA McCloskey: "Posttranscriptional Modification of tRNA in Thermophilic Archaea (Archaebacteria)", J. Bacteriol. , 1991 , 173  (10), pp. 3138-3148 ( PMC 207908 (free full text); PMID 1708763 ).
  6. ↑ Masakatsu Watanabe, Mami Matsuo, Sonoko Tanaka, Hiroshi Akimoto, Shuichi Asahi, Susumu Nishimura, Jon R. Katzen, Takeshi Hashizume, Pamela F. Crain, James A. McCloskey, Norihiro Okada: "Biosynthesis of Archaeosine, a Novel Derivative of 7 -Deazaguanosine Specific to Archaeal tRNA, Proceeds via a Pathway Involving Base Replacement on the tRNA Polynucleotide Chain ", The Journal of Biological Chemistry , 1997 , 272 , pp. 20146-20151 ( doi : 10.1074 / jbc.272.32.20146 , PMID 9242689 , PDF ).

Web links

  • Archaeosin's Modification Summary in the Modomics database, accessed January 14, 2014.