Transcription regulator that can specifically activate or repress expression of target genes (By similarity). Regulates genes involved in production of antibiotic and exoenzyme virulence determinants in the phytopathogen (PubMed:9402023). Required for the expression of the virulence protein evf during Drosophila melanogaster infection (PubMed:12612613). Homodimer. Pleiotropic, with decreased production of exoenzymes such as pectate lyase (Pel), cellulase and protease Prt. Has a 50% decrease in potato macerationafter 96 hours. Dramatically reduces transcription of carA, the antibiotic carbapenem biosynthetic gene. Belongs to the SlyA family.