Isolation and structural properties of aerial mycelium differentiation-inhibitory substances against Streptomyces scabiei causing potato common scab

Abstract

The inhibitor of aerial mycelium differentiation in Streptomyces scabiei, a pathogen of potato common scab, was searched. An actinomycete isolated from the field was found to produce inhibitors and two active substances were isolated as single peaks with HPLC. The molecular weights of inhibitors A and B were 1156.5 and 1140.5, respectively. Numbers of functional groups in inhibitor A were estimated by derivatization reactions. Inhibitor A seems to be a non-peptidic or non-saccharic substance because enzymatic treatments with pepsin, trypsin or glycosidases did not affect the LC-MS profiles or inhibitory activity.