Skip to main content
NCBI home page
Journal of Bacteriology logoLink to Journal of Bacteriology
. 1975 Sep;123(3):1131–1138. doi: 10.1128/jb.123.3.1131-1138.1975

p-Aminobenzoate-p-aminobenzoate.

J F Kane, H D O'Brien
PMCID: PMC235837  PMID: 239922

Abstract

p-Aminobenzoate (PABA) synthase from Bacillus subtilis is an aggregate composed of two nonidentical subunits and has the following properties. (i) In crude extracts this enzyme catalyzes the formation of PABA in the presence of chorismate and either glutamine (amidotransferase) or ammonia (aminase). The amidotransferase activity is about 5- to 10-fold higher than the aminase activity and is stable for at least 1 week when frozen at -70 C. (II) Although no divalent cation requirement could be demonstrated with crude extracts, 2 mM ethylene-diaminetetraacetic acid completely inhibits both activities. (iii) After ammonium sulfate fractionation both the aminase and amidotransferase activities require Mg2+ and guanosine in addition to the substrates indicated above for optimal activity. The guanosine requirement can be replaced by guanosine 5'-monophosphate, guanosine 5'-diphosphate, and guanosine 5'-triphosphate but not by guanine, adenosine 5'-triphosphate, uridine 5'-triphosphate, cytidine 5'-triphosphate, thymidine 5'-triphosphate, inorganic phosphate, and phosphoribosylpyrophosphate. Furthermore, at a pH above 7.4 or below 6.4 activity is rapidly lost a 4 C, or -60 C. (IV) The enzyme is composed of two non-identical subunits, designated subunit A and subunit X. Subunit A has an estimated molecular weight of 31,000, whereas subunit X has an estimated molecular weight of 19,000. Subunit A has aminase activity but no amidotransferase activity; a mutation at the pabA locus results in the loss of PABA synthase activity. Subunit X, which is also a component of the anthranilate synthase complex, has no PABA synthase activity itself but complexes with subunit A to give an AX aggregate that can use glutamine as a substrate. (v) The molecular weight of the AX complex has been estimated at 50,000, suggesting a 1:1 ratio of subunits. (vi) The enzyme is readily associated and dissociated.

Full text

PDF
1131

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Altendorf K. H., Bacher A., Lingens F. An intermediate involved in the formation of 4-aminobenzoic acid from chorismic acid in aerobacter aerogenes. FEBS Lett. 1969 Jun;3(5):319–321. doi: 10.1016/0014-5793(69)80167-5. [DOI] [PubMed] [Google Scholar]
  2. Altendorf K. H., Gilch B., Lingens F. Biosynthesis of 4-aminobenzoic acid in Aerobacter aerogenes. FEBS Lett. 1971 Aug 1;16(2):95–98. doi: 10.1016/0014-5793(71)80341-1. [DOI] [PubMed] [Google Scholar]
  3. Buchanan J. M. The amidotransferases. Adv Enzymol Relat Areas Mol Biol. 1973;39:91–183. doi: 10.1002/9780470122846.ch2. [DOI] [PubMed] [Google Scholar]
  4. GIBSON F., GIBSON M., COX G. B. THE BIOSYNTHESIS OF P-AMINOBENZOIC ACID FROM CHORISMIC ACID. Biochim Biophys Acta. 1964 Mar 16;82:637–638. doi: 10.1016/0304-4165(64)90465-9. [DOI] [PubMed] [Google Scholar]
  5. Hendler S., Srinivasan P. R. An intermediate in the conversion of chorismate to p-aminobenzoate. Biochim Biophys Acta. 1967 Aug 29;141(3):656–658. doi: 10.1016/0304-4165(67)90200-0. [DOI] [PubMed] [Google Scholar]
  6. Hoch S. O., Anagnostopoulos C., Crawford I. P. Enzymes of the tryptophan operon of Bacillus subtilis. Biochem Biophys Res Commun. 1969 Jun 27;35(6):838–844. doi: 10.1016/0006-291x(69)90700-1. [DOI] [PubMed] [Google Scholar]
  7. Huang M., Gibson F. Biosynthesis of 4-aminobenzoate in Escherichia coli. J Bacteriol. 1970 Jun;102(3):767–773. doi: 10.1128/jb.102.3.767-773.1970. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Huang M., Pittard J. Genetic analysis of mutant strains of Escherichia coli requiring p-aminobenzoic acid for growth. J Bacteriol. 1967 Jun;93(6):1938–1942. doi: 10.1128/jb.93.6.1938-1942.1967. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Jensen R. A. A biochemical basis for apparent abortive transformation in Bacillus subtilis. Genetics. 1968 Dec;60(4):707–717. doi: 10.1093/genetics/60.4.707. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Kane J. F., Holmes W. M., Jensen R. A. Metabolic interlock. The dual function of a folate pathway gene as an extra-operonic gene of tryptophan biosynthesis. J Biol Chem. 1972 Mar 10;247(5):1587–1596. [PubMed] [Google Scholar]
  11. Kane J. F., Homes W. M., Smiley K. L., Jr, Jensen R. A. Rapid regulation of an anthranilate synthase aggregate by hysteresis. J Bacteriol. 1973 Jan;113(1):224–232. doi: 10.1128/jb.113.1.224-232.1973. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
  13. Patel N., Holmes W. M., Kane J. F. Homologous and hybrid complexes of anthranilate synthase from Bacillus species. J Bacteriol. 1974 Jul;119(1):220–227. doi: 10.1128/jb.119.1.220-227.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Patel N., Moyed H. S., Kane J. F. Xanthosine-5'-phosphate amidotransferase from Escherichia coli. J Biol Chem. 1975 Apr 10;250(7):2609–2613. [PubMed] [Google Scholar]
  15. SRINIVASAN P. R., WEISS B. The biosynthesis of p-aminobenzoic acid: studies on the origin of the amino group. Biochim Biophys Acta. 1961 Aug 19;51:597–599. doi: 10.1016/0006-3002(61)90623-0. [DOI] [PubMed] [Google Scholar]
  16. Sawula R. V., Crawford I. P. Anthranilate synthetase of Acinetobacter calcoaceticus. Separation and partial characterization of subunits. J Biol Chem. 1973 May 25;248(10):3573–3581. [PubMed] [Google Scholar]
  17. Weiss B., Srinivasan P. R. THE BIOSYNTHESIS OF p-AMINOBENZOIC ACID. Proc Natl Acad Sci U S A. 1959 Oct;45(10):1491–1494. doi: 10.1073/pnas.45.10.1491. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Zalkin H. Anthranilate synthetase. Adv Enzymol Relat Areas Mol Biol. 1973;38:1–39. doi: 10.1002/9780470122839.ch1. [DOI] [PubMed] [Google Scholar]

Articles from Journal of Bacteriology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES