Control of teichuronic acid synthesis in Bacillus licheniformis ATCC 9945

Biosynthesis, and more specifically, regulatory control of the anionic polymers teichoic and teichuronic acid, in bacterial cell walls has provided an area of continued interest. The scheme whereby regulation could be achieved through the intermediates of one pathway repressing the synthesis of enzymes of the other [ 1 ] was questioned when glycerol containing intermediates, unique to teichoic acid, was reported not to repress the synthesis of teichuronic acid [2]. That such intermediates could modulate enzyme activity was, however, conceded. A chemostat investigation of the teichoic acid-synthesising enzymes in Bacillus licheniformis presented evidence for the rapid inactivation of CDP glycerol pyrophosphorylase during changeover from non-phosphate to phosphate limited growth [3]. The mechanism of inactivation was not investigated, but was shown to be independent of new protein synthesis. In [4] cessation of teichoic acid synthesis in phosphate limited cells of Bacillus sub tilis was reported not to be effected through a loss of CDP glycerol pyrophosphorylase activity. And, because new protein synthesis was required, an involvement of one of the teichuronic acid-synthesising enzymes in teichoic acid disappearance was tentatively assumed [ 51. These observations are indicative of a difference in the polymer control mechanism in the two organisms. Here, we describe the behavlour of the teichuronic acid-synthesising enzymes in B. licheniformis during transitions from phosphate and non-phosphate limited growth and provide an insight into the mode of polymer control. 2. Materials and methods