title: Carbamoyl-phosphate synthetases from Neurospora crassa. Immunological relatedness of the enzymes from Neurospora, bacteria, yeast, and mammals.
abstract: Neurospora crassa contains two carbamoyl-phosphate synthetases: a mitochondrial enzyme (CPS-A) which supplies carbamoyl phosphate for arginine biosynthesis, and a nuclear enzyme whose product is used for the synthesis of pyrimidines. We have prepared antiserum against a highly purified preparation of the large subunit of CPS-A and have used the antiserum to demonstrate that the large subunit is, like most mitochondrially localized proteins, initially synthesized as a higher molecular weight precursor. The CPS-A antiserum cross-reacts with the nuclear enzyme, allowing us to identify the product of the complex N. crassa pyr-3 genetic locus as a protein with a subunit molecular weight of 180,000. Finally, we have found that the CPS-A antiserum also cross-reacts with carbamoyl-phosphate synthetases from bacteria, yeast, and mammals. The immunological relatedness of carbamoyl-phosphate synthetases from such diverse species suggests that the protein sequences required for carbamoyl phosphate production have been highly conserved during the course of evolution.
authors.forename: S A
authors.initials: SA
authors.lastname: Ness
authors.forename: R L
authors.initials: RL
authors.lastname: Weiss
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D005075:Biological Evolution; D002222:Carbamoyl-Phosphate Synthase (Ammonia) / Q000032:analysis / Q000276:immunology* / Q000302:isolation & purification; D002467:Cell Nucleus / Q000201:enzymology; D004792:Enzyme Precursors / Q000032:analysis; D004926:Escherichia coli / Q000201:enzymology; D007106:Immune Sera / Q000276:immunology; D007163:Immunosorbent Techniques; D007668:Kidney / Q000201:enzymology; D008025:Ligases / Q000276:immunology*; D008099:Liver / Q000201:enzymology; D008928:Mitochondria / Q000201:enzymology*; D008970:Molecular Weight; D009154:Mutation; D009491:Neurospora / Q000201:enzymology*; D009492:Neurospora crassa / Q000201:enzymology*; D051381:Rats; D012441:Saccharomyces cerevisiae / Q000201:enzymology
chemical_list: D004792:Enzyme Precursors; D007106:Immune Sera; D008025:Ligases; D002222:Carbamoyl-Phosphate Synthase (Ammonia)