Absence of Sporulation

Bacillus Production Strains on the Factory Floor Some Examples 7.9.1 

The global demand for nucleotides in 2009 was approximately 23 000 metric tons according to Ajinomoto Co. of Japan, the nucleotide market leader with a market share of about 40%. Other competitors in the field are CJ Group and Daesang Group of Korea, Kirin Kyowa Foods Company of Japan, and Star Lake Bioscience of China. The demand for nucleotides grows in parallel with the market for processed foods (Source FLEXNEWS 06/10/2010). 

The purine nucleotides IMP and GMP are produced in a chemical process step by phosphorylation of the corresponding nucleosides, which are obtained by fermentation [278- 280]. The phosphorylation agent is phosphoryl chloride [281]. The traditional purine nucleoside production strains are mutants of B. amyloliq-uefaciens, in the older literature designated as B. subtUis K, but B. subtUis strains might also be used at industrial scale. 

In the purine degradation pathway IMP and GMP are dephosphorylated by nonspecified phosphatases to the corresponding nucleosides, which can leave the bacteria either spontaneously or facilitated by an exporter, for example, PbuE [290, 291]. Further degradation of the nucleosides to the nucleobases is catalyzed by the nucleotide phosphorylases PunA and DeoD [292]. The bases can be salvaged by Hpt-catalyzed reactions with PRPP to IMP and GMP. 

A common property of all Bacillus purine production strains is their aux-otrophy for adenine caused by a dysfunctional adenylosuccinate synthase gene (purA) of the AMP-specific branch of the purine pathway. Furthermore, the 

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