Mutations at pipX Suppress Lethality of P-II-Deficient Mutants of Synechococcus elongatus PCC 7942

作者：Espinosa Javier; Angel Castells Miguel; Boumediene Laichoubi Karim; Contreras Asuncion^*

来源：Journal of Bacteriology, 2009, 191(15): 4863-4869.

DOI：10.1128/JB.00557-09

The P-II proteins are found in all three domains of life as key integrators of signals reflecting the balance of nitrogen and carbon. Genetic inactivation of P-II proteins is typically associated with severe growth defects or death. However, the molecular basis of these defects depends on the specific functions of the proteins with which P-II proteins interact to regulate nitrogen metabolism in different organisms. In Synechococcus elongatus PCC 7942, where P-II forms complexes with the NtcA coactivator PipX, attempts to engineer P-II-deficient strains failed in a wild-type background but were successful in pipX null mutants. Consistent with the idea that P-II is essential to counteract the activity of PipX, four different spontaneous mutations in the pipX gene were found in cultures in which glnB had been genetically inactivated.

• 出版日期2009-8