Protein Family Models

Queuosine (Q) biosynthesis protein, or S-adenosylmethionine:tRNA -ribosyltransferase-isomerase, is required for the synthesis of the queuosine precursor (oQ). It catalyses the transfer and isomerisation of the ribose moiety from AdoMet to the 7-aminomethyl group of 7-deazaguanine (preQ1-tRNA) to form epoxyqueuosine (oQ-tRNA). Q is a hypermodified nucleoside usually found at the first position of the anticodon of asparagine, aspartate, histidine, and tyrosine tRNAs [1,2]. In Streptococcus gordonii , QueA has been shown to play a role in the regulation of arginine deiminase genes [3]. [1]. 8347586. A new function of S-adenosylmethionine: the ribosyl moiety of AdoMet is the precursor of the cyclopentenediol moiety of the tRNA wobble base queuine. Slany RK, Bosl M, Crain PF, Kersten H;. Biochemistry 1993;32:7811-7817. [2]. 12731872. Kinetic mechanism of the tRNA-modifying enzyme S-adenosylmethionine:tRNA ribosyltransferase-isomerase (QueA). Van Lanen SG, Iwata-Reuyl D;. Biochemistry. 2003;42:5312-5320. [3]. 18552185. Environmental and growth phase regulation of the Streptococcus gordonii arginine deiminase genes. Liu Y, Dong Y, Chen YY, Burne RA;. Appl Environ Microbiol. 2008;74:5023-5030. (from Pfam)

Date:

2024-10-16