Aminoacyl-tRNA synthetases specifically charge tRNAs with their cognat
e amino acids. A prototype for the most complex aminoacyl-tRNA synthet
ases is the four-subunit glycyl-tRNA synthetase from Escherichia coli,
encoded by two open reading frames. We examined the glycyl-tRNA synth
etase gene from Chlamydia trachomatis, a genetically isolated bacteriu
m, and identified only a single open reading frame for the chlamydial
homolog (glyQS). This is the first report of a prokaryotic glycyl-tRNA
synthetase encoded by a single gene.