The LytTR domain is a DNA-binding, potential winged helix-turn-helix (wHTH) present in AlgR/AgrA/LytR family of transcription factors that regulate virulence factor and toxin gene expression in pathogenic bacteria PMID:18462677. It is named after Bacillus subtilis LytT and Staphylococcus aureus LytR response regulators, involved in the regulation of cell autolysis PMID:12034833.

The LytTR domain is found in several bacterial cytoplasmic proteins that regulate the production of important virulence factors, like extracellular polysaccharides, toxins and bacteriocins. These response regulators of the microbial two-component signal transduction systems contain N-terminal cheY-like domains and the LytTR domain in the C-terminal part is expected to bind to specific DNA sequences in the upstream regions of target genes PMID:12367524. Other domains found N-terminally of LytTR are an ATP-binding domain of ABC-type transporter family and a PAS domain. Besides these cytoplasmic proteins, LytTR also occurs in membrane-bound bacterial proteins. The N-terminal parts of these proteins contain three to eight predicted transmembrane segments or the transmembrane MHYT domain.

According to secondary structure predictions the LytTR domain consists of four beta-strands and three alpha-helices. The structure is predicted to form a novel type of DNA-binding domain, showing similarity to the 'winged HTH' or 'winged helix' proteins PMID:12034833,PMID:12367524.

INTERPRO:IPR007492, PFAM:PF04397