Proc Natl Acad Sci U S A. 2013 Apr 2;110(14):5540-5. doi:10.1073/pnas.1303090110

Campbell JH, O'Donoghue P, Campbell AG, Schwientek P, Sczyrba A, Woyke T, Söll D, Podar M.

UGA is an additional glycine codon in uncultured SR1 bacteria from the human microbiota.

“Coexpression of SR1 glycyl-tRNA synthetase and tRNA(Gly)UCA in Escherichia coli yields significant β-galactosidase activity in vivo from a lacZ gene containing an in-frame TGA codon.”