Delaminomycins, novel nonpeptide extracellular matrix receptor antagonist and a new class of potent immunomodulator. I. Taxonomy, fermentation, isolation and biological activity.

In order to develop a new class of immunomodulator we have searched for a low molecular weight inhibitors of cell adhesion to components of extracellular matrix (ECM), fibronectin (FN), laminin (LM) and collagen type IV (CL), and succeeded to find a group of novel antibiotics, named delaminomycins. Delaminomycins were isolated from the mycelium and cultured broth of Streptomyces albulus MJ202-72F3. It was purified by use of centrifugal partition chromatography (CPC), preparative reverse phase HPLC and Sephadex LH-20 and was obtained as a white powder. Delaminomycins with inhibitory activity for cell adhesion to ECM components suppressed immune responses in vitro and in vivo and exhibited antimicrobial activity on Gram-positive bacteria.