Manganese requirement of phosphoglycerate phosphomutase and its consequences for growth and sporulation of Bacillus subtilis

Abstract

In the absence of manganese, rapidly metabolizable carbohydrates such as glucose or glycerol are not completely metabolized by B. subtilis growing in a nutrient sporulation medium; 3 phosphoglyceric acid (3PGA) accumulates inside the cells, growth stops at a low cell titer, and normal sporulation remains suppressed (no prespore septa). Upon the addition of manganese, 3PGA disappears, growth resumes, and normal sporulation takes place. These effects result from a specific manganese requirement of phosphoglycerate phosphomutase which catalyzes the interconversion of 3PGA and 2 phosphoglyceric acid (2PGA). Other metal ions cannot replace manganese, for which the enzyme has an apparent Km of 22 mM.