This family consists of several phage antitermination protein Q and related bacterial sequences. Phage 82 gene Q encodes a phage-specific positive regulator of late gene expression, thought, by analogy to the corresponding gene of phage lambda, to be a transcription antiterminator [1].

1: Bacteriophage 82 gene Q and Q protein. Sequence, overproduction, and activity as a transcription antiterminator in vitro. Goliger JA, Roberts JW; J Biol Chem 1987;262:11721-11725. PMID:3624233