Formation of a clear zone on tannin-treated brain heart infusion agar by a Streptococcus sp. isolated from feces of koalas.

Gram-positive cocci, isolated from the feces of koalas and identified as Streptococcus bovis biotype I, formed a distinct clear zone on tannin-treated brain heart infusion agar, suggesting that this isolate has the unique characteristic of degrading the tannin-protein complex.