6.3.5.7 ATP + Asp-tRNAAsn + L-glutamine - 6.3.5.7 ATP + Glu-tRNAGln + L-glutamine - 6.3.5.7 ATP + Glu-tRNAGln + L-glutamine organisms lacking Gln-tRNA synthetase produce Gln-tRNAGln from misacylated Glu-tRNAGln through the transamidation activity of Glu-tRNAGln amidotransferase. The enzyme hydrolyzes Gln to Glu and NH3, using the latter product to transamidate Glu-tRNAGln in concert with ATP hydrolysis 6.3.5.7 ATP + Glu-tRNAGln + L-glutamine the enzyme produces Gln-tRNAGln required for plastidal protein biosynthesis 6.3.5.7 ATP + Glu-tRNAGln + L-glutamine disruption of this operon is lethal. Transamidation is the only pathway to Gln-tRNAGln in Bacillus subtilis. The enzyme furnishes a means for formation of correctly charged Gln-tRNAGln through the transamidation of misacylated Glu-tRNAGln, functionally replacing the lack of glutaminyl-tRNA synthetase activity in Gram-positive eubacteria, cyanobacteria, archaea and organelles 6.3.5.7 ATP + Glu-tRNAGln + L-glutamine + H2O -