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J Bacteriol. 1995 April; 177(8): 1947–1951.
PMCID: PMC176834

Evidence for the presence of urease apoprotein complexes containing UreD, UreF, and UreG in cells that are competent for in vivo enzyme activation.


In vivo activation of Klebsiella aerogenes urease, a nickel-containing enzyme, requires the presence of functional UreD, UreF, and UreG accessory proteins and is further facilitated by UreE. These accessory proteins are proposed to be involved in metallocenter assembly (M. H. Lee, S. B. Mulrooney, M. J. Renner, Y. Markowicz, and R. P. Hausinger, J. Bacteriol. 174:4324-4330, 1992). A series of three UreD-urease apoprotein complexes are present in cells that express ureD at high levels, and these complexes are thought to be essential for in vivo activation of the enzyme (I.-S. Park, M. B. Carr, and R. P. Hausinger, Proc. Natl. Acad. Sci. USA 91:3233-3237, 1994). In this study, we describe the effect of accessory gene deletions on urease complex formation. The ureE, ureF, and ureG gene products were found not to be required for formation of the UreD-urease complexes; however, the complexes from the ureF deletion mutant exhibited delayed elution during size exclusion chromatography. Because these last complexes were of typical UreD-urease sizes according to native gel electrophoretic analysis, we propose that UreF alters the conformation of the UreD-urease complexes. The same studies revealed the presence of an additional series of urease apoprotein complexes present only in cells containing ureD, ureF, and ureG, along with the urease subunit genes. These new complexes were shown to contain urease, UreD, UreF, and UreG. We propose that the UreD-UreF-UreG-urease apoprotein complexes represent the activation-competent form of urease apoprotein in the cell.

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Selected References

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  • Blake MS, Johnston KH, Russell-Jones GJ, Gotschlich EC. A rapid, sensitive method for detection of alkaline phosphatase-conjugated anti-antibody on Western blots. Anal Biochem. 1984 Jan;136(1):175–179. [PubMed]
  • Hartman FC, Harpel MR. Structure, function, regulation, and assembly of D-ribulose-1,5-bisphosphate carboxylase/oxygenase. Annu Rev Biochem. 1994;63:197–234. [PubMed]
  • Laemmli UK. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. [PubMed]
  • Lee MH, Mulrooney SB, Renner MJ, Markowicz Y, Hausinger RP. Klebsiella aerogenes urease gene cluster: sequence of ureD and demonstration that four accessory genes (ureD, ureE, ureF, and ureG) are involved in nickel metallocenter biosynthesis. J Bacteriol. 1992 Jul;174(13):4324–4330. [PMC free article] [PubMed]
  • LOWRY OH, ROSEBROUGH NJ, FARR AL, RANDALL RJ. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed]
  • Maier T, Jacobi A, Sauter M, Böck A. The product of the hypB gene, which is required for nickel incorporation into hydrogenases, is a novel guanine nucleotide-binding protein. J Bacteriol. 1993 Feb;175(3):630–635. [PMC free article] [PubMed]
  • Matsudaira P. Limited N-terminal sequence analysis. Methods Enzymol. 1990;182:602–613. [PubMed]
  • Mobley HL, Hausinger RP. Microbial ureases: significance, regulation, and molecular characterization. Microbiol Rev. 1989 Mar;53(1):85–108. [PMC free article] [PubMed]
  • Mulrooney SB, Hausinger RP. Sequence of the Klebsiella aerogenes urease genes and evidence for accessory proteins facilitating nickel incorporation. J Bacteriol. 1990 Oct;172(10):5837–5843. [PMC free article] [PubMed]
  • Mulrooney SB, Pankratz HS, Hausinger RP. Regulation of gene expression and cellular localization of cloned Klebsiella aerogenes (K. pneumoniae) urease. J Gen Microbiol. 1989 Jun;135(6):1769–1776. [PubMed]
  • Park IS, Carr MB, Hausinger RP. In vitro activation of urease apoprotein and role of UreD as a chaperone required for nickel metallocenter assembly. Proc Natl Acad Sci U S A. 1994 Apr 12;91(8):3233–3237. [PubMed]
  • Waugh R, Boxer DH. Pleiotropic hydrogenase mutants of Escherichia coli K12: growth in the presence of nickel can restore hydrogenase activity. Biochimie. 1986 Jan;68(1):157–166. [PubMed]

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