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Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1969 Nov;64(3):1072–1078. doi: 10.1073/pnas.64.3.1072

In vitro FORMATION OF AN ACTIVE MULTIENZYME COMPLEX IN THE TRYPTOPHAN PATHWAY OF Neurospora crassa*

Angel Arroyo-Begovich 1, John A DeMoss 1
PMCID: PMC223345  PMID: 5264137

Abstract

A multienzyme complex that catalyzes the anthranilate synthetase, phosphoribosylanthranilate (PRA) isomerase, and indoleglycerolphosphate (InGP) synthetase reactions was produced in vitro when extracts from a tryp-1 mutant and a tryp-2 mutant of Neurospora crassa were mixed. The sedimentation values and the molecular weights for the interacting components obtained from the mutants were estimated by sucrose gradients and by gel filtration on Sephadex columns. The component coded for by the tryp-2 gene (a-component) which is present in the tryp-1-17 mutant has a sedimentation coefficient of 4.5S and molecular weight of 70,000. The component coded for by the tryp-1 gene (i-component) which is present in the tryp-2-6 mutant has a sedimentation coefficient 7.5S and a molecular weight of 170,000. The complex formed in vitro had similar properties to those previously reported for the wild-type complex. A Q10 value of 3 and an apparent activation energy of 18,000 cal/mole were calculated for the formation of the complex from the two components.

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Selected References

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

  1. DEMOSS J. A. THE CONVERSION OF SHIKIMIC ACID TO ANTHRANILIC ACID BY EXTRACTS OF NEUROSPORA CRASSA. J Biol Chem. 1965 Mar;240:1231–1235. [PubMed] [Google Scholar]
  2. DeMoss J. A., Jackson R. W., Chalmers J. H., Jr Genetic control of the structure and activity of an enzyme aggregate in the tryptophan pathway of Neurospora crassa. Genetics. 1967 Jul;56(3):413–424. doi: 10.1093/genetics/56.3.413. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. DeMoss J. A., Wegman J. An enzyme aggregate in the tryptophan pathway of Neurospora crassa. Proc Natl Acad Sci U S A. 1965 Jul;54(1):241–247. doi: 10.1073/pnas.54.1.241. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Gaertner F. H., DeMoss J. A. Purification and characterization of a multienzyme complex in the tryptophan pathway of Neurospora crassa. J Biol Chem. 1969 May 25;244(10):2716–2725. [PubMed] [Google Scholar]
  5. KAGI J. H., VALLEE B. L. The role of zinc in alcohol dehydrogenase. V. The effect of metal-binding agents on thestructure of the yeast alcohol dehydrogenase molecule. J Biol Chem. 1960 Nov;235:3188–3192. [PubMed] [Google Scholar]
  6. 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]
  7. SAMEJIMA T., KAMATA M., SHIBATA K. Dissociation of bovine liver catalase at low pH. J Biochem. 1962 Mar;51:181–187. doi: 10.1093/oxfordjournals.jbchem.a127518. [DOI] [PubMed] [Google Scholar]
  8. Wegman J., DeMoss J. A. The enzymatic conversion of anthranilate to indolylglycerol phosphate in Neurospora crassa. J Biol Chem. 1965 Oct;240(10):3781–3788. [PubMed] [Google Scholar]

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