CYP26A1 and infection: A number of similarities were observed in the response to the potential commensal strain ATCC 51561 (NPPB and CYP1A1); however, a number of genes (e.g. MT1E, NOTCH3, CYP26A1, HEY1) found to be differentially expressed by infection with C. concisus UNSWCD or BAA-1457 were not modulated by this strain.