CLONING AND EXPRESSION OF A UNIQUE INORGANIC PYROPHOSPHATASE FROM BACILLUS-SUBTILIS - EVIDENCE FOR A NEW FAMILY OF ENZYMES

An open reading frame located in the COTF-TETB intergenic region of Ba cillus subtilis was cloned and expressed in Escherichia coli and shown to encode inorganic pyrophosphatase (PPase). The isolated enzyme is M n2+-activated, like the authentic PPase isolated from B. subtilis. Alt hough 13 functionally important active site residues are conserved in all 31 soluble PPase sequences so far identified, only two of them are conserved in B. subtilis PPase. This suggests that B. subtilis PPase represents a new family of soluble PPases (a Bs family), putative memb ers of which were found in Archaeoglobus fulgidus, Methanococcus janna schii, Streptococcus mutans and Streptococcus gordonii. (C) 1998 Feder ation of European Biochemical Societies.