P. Nygaard et al., ROLE OF ADENINE DEAMINASE IN PURINE SALVAGE AND NITROGEN-METABOLISM AND CHARACTERIZATION OF THE ADE GENE IN BACILLUS-SUBTILIS, Journal of bacteriology, 178(3), 1996, pp. 846-853
The isolation of mutants defective in adenine metabolism in Bacillus s
ubtilis has provided a tool that has made it possible to investigate t
he role of adenine deaminase in adenine metabolism in growing cells. A
denine deaminase is the only enzyme that can deaminate adenine compoun
ds in B. subtilis, a reaction which is important for adenine utilizati
on as a purine and also as a nitrogen source. The uptake of adenine is
strictly coupled to its further metabolism. Salvaging of adenine is i
nhibited by the stringent response to amino acid starvation, while the
deamination of adenine is not. The level of adenine deaminase was red
uced when exogenous guanosine served as the purine source and when glu
tamine served as the nitrogen source. The enzyme level was essentially
the same whether ammonia or purines served as the nitrogen source. Re
duced levels mere seen on poor carbon sources. The ade gene was cloned
, and the nucleotide sequence and mRNA analyses revealed a single-gene
operon encoding a 65-kDa protein. By transductional crosses, we have
located the ade gene to 130 degrees on the chromosomal map.