title: Regulation of pyrimidine synthesis in Pseudomonas resinovorans.
abstract: OBJECTIVE
  To investigate the regulation of de novo pyrimidine biosynthesis in the bacterium Pseudomonas resinovorans ATCC 14235.
  
  
  RESULTS
  The pyrimidine biosynthetic pathway enzymes were measured in cell extracts from P. resinovorans ATCC 14235 and from an auxotroph lacking orotate phosphoribosyltransferase activity. Pyrimidine biosynthetic pathway enzyme activities in ATCC 14235 were affected by the addition of pyrimidine bases to the culture medium. The de novo enzyme activities of the phosphoribosyltransferase mutant strain increased after pyrimidine starvation indicating possible repression of the pathway by a pyrimidine-related compound. Aspartate transcarbamoylase activity in ATCC 14235 was inhibited in vitro by ATP, UTP and pyrophosphate.
  
  
  CONCLUSIONS
  Pyrimidine biosynthesis in P. resinovorans was regulated at the level of enzyme synthesis and at the level of activity for aspartate transcarbamoylase. Its regulation of enzyme synthesis seemed to be similar to what has been observed in the taxonomically related species Pseudomonas oleovorans.
  
  
  CONCLUSIONS
  This study found that pyrimidine biosynthesis is regulated in P. resinovorans. This could prove helpful to future studies investigating polyhydroxyalkanoate production by the bacterium.
authors.affiliation: Department of Chemistry and Biochemistry, South Dakota State University, Brookings, SD, USA. thomas.west@sdstate.edu
authors.forename: T P
authors.initials: TP
authors.lastname: West
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology; D001221:Aspartate Carbamoyltransferase / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004794:Enzyme Repression; D015964:Gene Expression Regulation, Bacterial; D009962:Orotate Phosphoribosyltransferase / Q000235:genetics / Q000378:metabolism; D011549:Pseudomonas / Q000235:genetics / Q000378:metabolism*; D011743:Pyrimidines / Q000096:biosynthesis*; D014544:Uridine Triphosphate / Q000494:pharmacology
chemical_list: D004791:Enzyme Inhibitors; D011743:Pyrimidines; D000255:Adenosine Triphosphate; D001221:Aspartate Carbamoyltransferase; D009962:Orotate Phosphoribosyltransferase; C030986:pyrimidine; D014544:Uridine Triphosphate