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. 1986 Jul;83(13):4626–4630. doi: 10.1073/pnas.83.13.4626

Structure of an intermolecular electron-transfer complex: p-cresol methylhydroxylase at 6.0-A resolution.

N Shamala, L W Lim, F S Mathews, W McIntire, T P Singer, D J Hopper
PMCID: PMC323794  PMID: 3460061

Abstract

The structure of p-cresol methylhydroxylase [4-cresol:(acceptor) oxidoreductase (methyl-hydroxylating), EC 1.17.99.1], a flavocytochrome c, has been determined at 6.0-A resolution. The structure analysis is based on two heavy-atom derivatives with anomalous scattering and 2-fold averaging about a noncrystallographic axis. The molecule is an alpha 2 beta 2 tetramer with a cytochrome subunit of Mr approximately 8500 and a flavoprotein subunit of Mr approximately 49,000. The flavoprotein subunits are tightly packed about the molecular 2-fold axis, whereas the cytochrome subunits are located on the outside of the molecule, each in a depression on the surface of a flavoprotein subunit. The results of this study have led to the following conclusions. The alpha 2 beta 2 quaternary structure of the enzyme is different from alpha beta as originally thought. The orientation of the cytochrome subunit and the surface complementarity of the cytochrome and flavoprotein subunits are clearly defined. The cytochrome subunit is similar in size to other small bacterial cytochromes but probably forms a distinct subclass. The titration (by substrate) behavior of the enzyme and other kinetic properties are rationalized by its quaternary structure.

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Selected References

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

  1. Argos P., Mathews F. S. The structure of ferrocytochrome b5 at 2.8 A resolution. J Biol Chem. 1975 Jan 25;250(2):747–751. [PubMed] [Google Scholar]
  2. Carter D. C., Melis K. A., O'Donnell S. E., Burgess B. K., Furey W. R., Jr, Wang B. C., Stout C. D. Crystal structure of Azotobacter cytochrome c5 at 2.5 A resolution. J Mol Biol. 1985 Jul 20;184(2):279–295. doi: 10.1016/0022-2836(85)90380-8. [DOI] [PubMed] [Google Scholar]
  3. Hopper D. J. Redox potential of the cytochrome c in the flavocytochrome p-cresol methylhydroxylase. FEBS Lett. 1983 Sep 5;161(1):100–102. doi: 10.1016/0014-5793(83)80738-8. [DOI] [PubMed] [Google Scholar]
  4. Keat M. J., Hopper D. J. P-cresol and 3,5-xylenol methylhydroxylases in Pseudomonas putida N.C.I.B. 9896. Biochem J. 1978 Nov 1;175(2):649–658. doi: 10.1042/bj1750649. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Koerber S. C., McIntire W., Bohmont C., Singer T. P. Resolution of the flavocytochrome p-cresol methylhydroxylase into subunits and reconstitution of the enzyme. Biochemistry. 1985 Sep 10;24(19):5276–5280. doi: 10.1021/bi00340a048. [DOI] [PubMed] [Google Scholar]
  6. Lederer F., Glatigny A., Bethge P. H., Bellamy H. D., Matthew F. S. Improvement of the 2.5 A resolution model of cytochrome b562 by redetermining the primary structure and using molecular graphics. J Mol Biol. 1981 Jun 5;148(4):427–448. doi: 10.1016/0022-2836(81)90185-6. [DOI] [PubMed] [Google Scholar]
  7. Lim L. W., Mathews F. S., Steenkamp D. J. Crystallographic study of the iron-sulfur flavoprotein trimethylamine dehydrogenase from the bacterium W3A1. J Mol Biol. 1982 Dec 25;162(4):869–876. doi: 10.1016/0022-2836(82)90551-4. [DOI] [PubMed] [Google Scholar]
  8. Mathews F. S. The structure, function and evolution of cytochromes. Prog Biophys Mol Biol. 1985;45(1):1–56. doi: 10.1016/0079-6107(85)90004-5. [DOI] [PubMed] [Google Scholar]
  9. McIntire W., Edmondson D. E., Hopper D. J., Singer T. P. 8 alpha-(O-Tyrosyl)flavin adenine dinucleotide, the prosthetic group of bacterial p-cresol methylhydroxylase. Biochemistry. 1981 May 26;20(11):3068–3075. doi: 10.1021/bi00514a013. [DOI] [PubMed] [Google Scholar]
  10. McIntire W., Hopper D. J., Singer T. P. p-Cresol methylhydroxylase. Assay and general properties. Biochem J. 1985 Jun 1;228(2):325–335. doi: 10.1042/bj2280325. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Shamala N., Lim L. W., Mathews F. S., McIntire W., Singer T. P., Hopper D. J. Preliminary X-ray study of p-cresol methylhydroxylase (flavocytochrome c) from Pseudomonas putida N.C.I.B. 9869. J Mol Biol. 1985 Jun 5;183(3):517–518. doi: 10.1016/0022-2836(85)90020-8. [DOI] [PubMed] [Google Scholar]
  12. Takano T., Dickerson R. E. Conformation change of cytochrome c. I. Ferrocytochrome c structure refined at 1.5 A resolution. J Mol Biol. 1981 Nov 25;153(1):79–94. doi: 10.1016/0022-2836(81)90528-3. [DOI] [PubMed] [Google Scholar]
  13. Wyckoff H. W., Doscher M., Tsernoglou D., Inagami T., Johnson L. N., Hardman K. D., Allewell N. M., Kelly D. M., Richards F. M. Design of a diffractometer and flow cell system for X-ray analysis of crystalline proteins with applications to the crystal chemistry of ribonuclease-S. J Mol Biol. 1967 Aug 14;27(3):563–578. doi: 10.1016/0022-2836(67)90059-9. [DOI] [PubMed] [Google Scholar]

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