Diversity of Archaeosine Synthesis in Crenarchaeota

Details

• Alternative Title:
  ACS Chem Biol
• Personal Author:
  Phillips, Gabriela ; Swairjo, Manal A. ; Gaston, Kirk W. ; Bailly, Marc ; Limbach, Patrick A. ; Iwata-Reuyl, Dirk ; de Crécy-Lagard, Valérie
• Description:
  Archaeosine (G(+)) is found at position 15 of many archaeal tRNAs. In Euryarchaeota, the G(+) precursor, 7-cyano-7-deazaguanine (preQ(0)), is inserted into tRNA by tRNA-guanine transglycosylase (arcTGT) before conversion into G(+) by ARChaeosine Synthase (ArcS). However, many Crenarchaeota known to harbor G(+) lack ArcS homologues. Using comparative genomics approaches, two families that could functionally replace ArcS in these organisms were identified: (1) GAT-QueC, a two-domain family with an N-terminal glutamine amidotransferase class-II domain fused to a domain homologous to QueC, the enzyme that produces preQ(0) and (2) QueF-like, a family homologous to the bacterial enzyme catalyzing the reduction of preQ(0) to 7-aminomethyl-7-deazaguanine. Here we show that these two protein families are able to catalyze the formation of G(+) in a heterologous system. Structure and sequence comparisons of crenarchaeal and euryarchaeal arcTGTs suggest the crenarchaeal enzymes have broader substrate specificity. These results led to a new model for the synthesis and salvage of G(+) in Crenarchaeota.
• Subjects:
  Amino Acid Sequence Archaeal Proteins Crenarchaeota Genomics Guanosine Molecular Sequence Data Phylogeny Sequence Alignment Substrate Specificity
• Source:
  ACS Chem Biol. 7(2):300-305.
• Pubmed ID:
  22032275
• Pubmed Central ID:
  PMC3289047
• Document Type:
  Journal Article
• Funding:
  RC2 GM092602/GM/NIGMS NIH HHS/United States ; RC2 GM092602-02/GM/NIGMS NIH HHS/United States ; U58 SO000016/SO/PHSPO CDC HHS/United States ; 1RC2GM092602−01/GM/NIGMS NIH HHS/United States
• Volume:
  7
• Issue:
  2
• Collection(s):
  CDC Public Access
• Main Document Checksum:
  urn:sha256:4eaa21114eb15807295b2af5c59886603785b283b639cec06cb297db5e0e0b96
• Download URL:
  https://stacks.cdc.gov/view/cdc/41849/cdc_41849_DS1.pdf
• File Type:
  [PDF - 2.68 MB ]