Abstract
Anticapsin is a new biologically active metabolite isolated from the culture filtrate of a strain of Streptomyces griseoplanus. The metabolite inhibits the formation of the hyaluronic acid capsules of Streptococcus pyogenes at a minimal concentration of 3 mcg/ml. Anticapsin (C9H13O4N), an amino acid (pKa=4.3; 10.1 in 66% DMF), is chemically related to bacilysin.
