Skip to main content
NCBI home page
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
. 1994 Apr 26;91(9):4034–4038. doi: 10.1073/pnas.91.9.4034

The structure of bacteriophage T7 lysozyme, a zinc amidase and an inhibitor of T7 RNA polymerase.

X Cheng 1, X Zhang 1, J W Pflugrath 1, F W Studier 1
PMCID: PMC43717  PMID: 8171031

Abstract

The lysozyme of bacteriophage T7 is a bifunctional protein that cuts amide bonds in the bacterial cell wall and binds to and inhibits transcription by T7 RNA polymerase. The structure of a mutant T7 lysozyme has been determined by x-ray crystallography and refined at 2.2-A resolution. The protein folds into an alpha/beta-sheet structure that has a prominent cleft. A zinc atom is located in the cleft, bound directly to three amino acids and, through a water molecule, to a fourth. Zinc is required for amidase activity but not for inhibition of T7 RNA polymerase. Alignment of the zinc ligands of T7 lysozyme with those of carboxypeptidase A and thermolysin suggests structural similarity among the catalytic sites for the amidase and these zinc proteases. Mutational analysis identified presumed catalytic residues for amidase activity within the cleft and a surface that appears to be the site of binding to T7 RNA polymerase. Binding of T7 RNA polymerase inhibits amidase activity.

Full text

PDF
4034

Images in this article

4036Image
on p.4036

Selected References

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

  1. Brünger A. T., Kuriyan J., Karplus M. Crystallographic R factor refinement by molecular dynamics. Science. 1987 Jan 23;235(4787):458–460. doi: 10.1126/science.235.4787.458. [DOI] [PubMed] [Google Scholar]
  2. Dunn J. J., Studier F. W. Complete nucleotide sequence of bacteriophage T7 DNA and the locations of T7 genetic elements. J Mol Biol. 1983 Jun 5;166(4):477–535. doi: 10.1016/s0022-2836(83)80282-4. [DOI] [PubMed] [Google Scholar]
  3. Inouye M., Arnheim N., Sternglanz R. Bacteriophage T7 lysozyme is an N-acetylmuramyl-L-alanine amidase. J Biol Chem. 1973 Oct 25;248(20):7247–7252. [PubMed] [Google Scholar]
  4. Matthews B. W., Remington S. J., Grütter M. G., Anderson W. F. Relation between hen egg white lysozyme and bacteriophage T4 lysozyme: evolutionary implications. J Mol Biol. 1981 Apr 25;147(4):545–558. doi: 10.1016/0022-2836(81)90399-5. [DOI] [PubMed] [Google Scholar]
  5. McAllister W. T., Wu H. L. Regulation of transcription of the late genes of bacteriophage T7. Proc Natl Acad Sci U S A. 1978 Feb;75(2):804–808. doi: 10.1073/pnas.75.2.804. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Moffatt B. A., Studier F. W. T7 lysozyme inhibits transcription by T7 RNA polymerase. Cell. 1987 Apr 24;49(2):221–227. doi: 10.1016/0092-8674(87)90563-0. [DOI] [PubMed] [Google Scholar]
  7. Schleif R., Greenblatt J., Davis R. W. Dual control of arabinose genes on transducing phage lambda-dara. J Mol Biol. 1971 Jul 14;59(1):127–150. doi: 10.1016/0022-2836(71)90417-7. [DOI] [PubMed] [Google Scholar]
  8. Silberstein S., Inouye M. Studies on the role of bacteriophage T7 lysozyme during phage infection. J Mol Biol. 1975 Jul 25;96(1):1–11. doi: 10.1016/0022-2836(75)90178-3. [DOI] [PubMed] [Google Scholar]
  9. Sousa R., Chung Y. J., Rose J. P., Wang B. C. Crystal structure of bacteriophage T7 RNA polymerase at 3.3 A resolution. Nature. 1993 Aug 12;364(6438):593–599. doi: 10.1038/364593a0. [DOI] [PubMed] [Google Scholar]
  10. Studier F. W. Bacteriophage T7. Science. 1972 Apr 28;176(4033):367–376. doi: 10.1126/science.176.4033.367. [DOI] [PubMed] [Google Scholar]
  11. Studier F. W., Rosenberg A. H., Dunn J. J., Dubendorff J. W. Use of T7 RNA polymerase to direct expression of cloned genes. Methods Enzymol. 1990;185:60–89. doi: 10.1016/0076-6879(90)85008-c. [DOI] [PubMed] [Google Scholar]
  12. Studier F. W. The genetics and physiology of bacteriophage T7. Virology. 1969 Nov;39(3):562–574. doi: 10.1016/0042-6822(69)90104-4. [DOI] [PubMed] [Google Scholar]
  13. Studier F. W. Use of bacteriophage T7 lysozyme to improve an inducible T7 expression system. J Mol Biol. 1991 May 5;219(1):37–44. doi: 10.1016/0022-2836(91)90855-z. [DOI] [PubMed] [Google Scholar]
  14. Vallee B. L., Auld D. S. Active-site zinc ligands and activated H2O of zinc enzymes. Proc Natl Acad Sci U S A. 1990 Jan;87(1):220–224. doi: 10.1073/pnas.87.1.220. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES