Occurrence of a large molecular size form of polyphosphate-glucose phosphotransferase in extracts of Mycobacterium tuberculosis H37Ra.

Extracts prepared by sonicating Mycobacterium tuberculosis H37Ra cells with subsequent centrifugation at 18,000 X g proved to contain a very large molecular size form of polyphosphate-glucose phosphotransferase. The enzyme was separable by polyacrylamide gel electrophoresis, DEAE-cellulose chromatography or ultracentrifugation. When rechromatographed at alkaline pH values, it gave rise to one of the soluble forms of lower molecular weight. The conversion also took place as a result of n-butanol extraction or salting out with ammonium sulfate and heating of dissolved pellet. Under certain conditions the lower-molecular weight enzyme converted to the higher-molecular weight form by association with a hitherto undefined cell constituent. It is assumed that both ionic and hydrophobic forces play a role in this interconversion phenomenon.