Citric Acid-induced Long Chain Formation of Streptococcus sp.

Abstract

In the presence of citrate, citrate-fermenting Streptococcus sp. KSM-1106 and KSM-1112 grew in long chains with innumerable cells. Divalent cations, such as Mn²⁺ and Ca²⁺, arrested the chain elongation. The results with citrate-negative and citrate-resistant variants suggested the involvement of citrate in the cell separation system. A dechaining activity, which was inhibited by citrate, could be demonstrated in the cell extract of strain KSM-1106. Such a special effect of citrate was not observed on the growth of strains of other lactic streptococci examined.