Phosphorolysis of sucrose by Pseudomonas putrefactions.

The phosphorolytic breakdown of sucrose was discovered several years ago by three groups of investigators working independently with two unrelated genera of bacteria. This mechanism was first described in Leuconostoc mesenteroides by Kagan, Latker, and Zfasman (1942). Without knowledge of this discovery Doudoroff, Kaplan, and Hassid (1942) found the same reaction in Pseudomonas saccharophila. It is interesting to record that before a published report of either finding was available, Gunsalus and Umbreit at Cornell University had also independently discovered the phosphorolysis of sucrose in Leuconostoc (private communication). Although a number of studies on the "sucrose phosphorylase" of P. saccharophila have been published (Doudoroff, Barker, and Hassid, 1947) and although a fairly intensive search has been made for similar enzymes in other bacteria and in green plants, no report of the occurrence of the enzyme in any but the two bacterial species in which it had been originally described has appeared to date. It seems, therefore, of interest to report that sucrose phosphorylase is found as an adaptive enzyme in Pseudomonas putrefacienw, a species that does not appear to be closely related to its congener, P. saccharophila. In addition to "sucrose phosphorylase," dry cell preparations of P. putrefaciens have been shown to contain the enzymes phosphoglucomutase and phosphohexoisomerase. Although the virtual absence of these enzymes in dry cell preparations of P. saccharophila had greatly facilitated the elucidation of the mechanism of phosphorolysis, the demonstration of their presence in P. putrefaciens establishes the expected link between the initial step of sucrose breakdown and the well-known steps of glycolytic degradation.