Identification of mutations involved in the requirement of potassium for growth of typical Melissococcus plutonius strains

Melissococcus plutonius is a fastidious honeybee pathogen, and the addition of KH(2)PO(4) to culture medium is required for its growth. Using genome sequences and a newly developed vector, we showed that mutations in genes encoding Na(+)/H(+) antiporter and cation-transporting ATPase are involved in the potassium requirement for growth.