Disease relevance of pncA

• Pyridine nucleotide cycle of Salmonella typhimurium: isolation and characterization of pncA, pncB, and pncC mutants and utilization of exogenous nicotinamide adenine dinucleotide [1].
• A major difference in the location of the pncA gene was found between the S. typhimurium and Escherichia coli linkage maps [1].

High impact information on pncA

• (i) pncX mutants have Tn10 insertion mutations near the pncA locus which reduce but do not eliminate the pncA product, nicotinamide deamidase [2].
• Transductions showed that the mutations producing these phenotypes were linked to both the pncA and nit genes, placing the gdhA locus between 23 and 30 U on the S. typhimurium chromosome [3].
• The pncA gene is located in a region in which there is a major inversion of the gene order in S. typhimurium as compared to that in E. coli [1].
• Mutants of Salmonella typhimurium LT-2 deficient in nicotinamidase activity (pncA) or nicotinic acid phosphoribosyltransferase activity (pncB) were isolated as resistant to analogs of nicotinic acid and nicotinamide [1].
• A series of Mud1 and Tn10 insertions were identified in the pncA chromosome region of Salmonella typhimurium which is responsible for the production of nicotinamide deamidase [4].

Biological context of pncA

• Merodiploid studies suggest a model whereby pncX and pncA form an operon with the major promoter occurring upstream from pncX [4].

References