A crytic transcriptional activator. When its expression is induced it relieves H-NS repression of the bgl operon. Acts independently of transcription factor LeuO. Forms a complex with RcsB; genetically both BglJ and RcsB are required to relieve bgl operon repression by H-NS and by StpA. Repressed by H-NS, activated by LeuO. Member of the yjjQ-bglJ operon. Truncated N-terminus.