Partial purification and properties of UDP-N-acetylmannosamine:N-acetylglucosaminyl pyrophosphorylundecaprenol N-acetylmannosaminyltransferase from Bacillus subtilis

An enzyme which catalyzes the conversion of GlcNAc-PP-undecaprenol into ManNAc(beta 1----4)GlcNAc-PP-undecaprenol, a key lipid intermediate in the de novo synthesis of various teichoic acids, was partially purified from the 20,000 x g supernatant fraction of Bacillus subtilis AHU 1035 cell homogenate. By means of ammonium sulfate precipitation, gel chromatography, and ion-exchange chromatography, the enzyme was purified about 70-fold, giving a preparation virtually free from substances obstructive to measurement of the N-acetylmannosaminyltransferase reaction. The enzyme was shown to be specific to UDP-ManNAc. The Km value for UDP-ManNAc was 4.4 microM, and the optimum pH was 7.3. The enzyme required 10 mM MgCl2, 0.3 M KCl, 25% glycerol, and 0.1% Nonidet P-40 to function at full activity.