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Robert P. Hausinger - One of the best experts on this subject based on the ideXlab platform.

  • Klebsiella aerogenes UreF: identification of the UreG binding site and role in enhancing the fidelity of urease activation.
    Biochemistry, 2012
    Co-Authors: Jodi L. Boer, Robert P. Hausinger
    Abstract:

    The Ni-containing active site of Klebsiella aerogenes urease is assembled through the concerted action of the UreD, UreE, UreF, and UreG accessory proteins. UreE functions as a metallochaperone tha...

  • Function of UreB in Klebsiella aerogenes urease.
    Biochemistry, 2011
    Co-Authors: Eric L. Carter, Jodi L. Boer, Mark A. Farrugia, Nicholas Flugga, Christopher L. Towns, Robert P. Hausinger
    Abstract:

    Urease from Klebsiella aerogenes is composed of three subunits (UreA–UreB–UreC) that assemble into a (UreABC)3 quaternary structure. UreC harbors the dinuclear nickel active site, whereas the functions of UreA and UreB remain unknown. UreD and UreF accessory proteins previously were suggested to reposition UreB and increase the level of exposure of the nascent urease active site, thus facilitating metallocenter assembly. In this study, cells were engineered to separately produce (UreAC)3 or UreB, and the purified proteins were characterized. Monomeric UreB spontaneously binds to the trimeric heterodimer of UreA and UreC to form (UreABC*)3 apoprotein, as shown by gel filtration chromatography, integration of electrophoretic gel band intensities, and mass spectrometry. Similar to the authentic urease apoprotein, the active enzyme is produced by incubation of (UreABC*)3 with Ni2+ and bicarbonate. Conversely, UreBΔ1–19, lacking the 19-residue potential hinge and tether to UreC, does not form a complex with (U...

  • Chemical Rescue of Klebsiella aerogenes Urease Variants Lacking the Carbamylated-Lysine Nickel Ligand†,‡
    Biochemistry, 1998
    Co-Authors: M.a. Pearson, R.a. Schaller, L.o. Michel, P.a. Karplus, Robert P. Hausinger
    Abstract:

    Klebsiella aerogenes urease possesses a dinuclear metallocenter in which two nickel atoms are bridged by carbamylated Lys217. To assess whether carbamate-specific chemistry is required for urease a...

  • chemical rescue of Klebsiella aerogenes urease variants lacking the carbamylated lysine nickel ligand
    Biochemistry, 1998
    Co-Authors: M.a. Pearson, R.a. Schaller, L.o. Michel, P.a. Karplus, Robert P. Hausinger
    Abstract:

    Klebsiella aerogenes urease possesses a dinuclear metallocenter in which two nickel atoms are bridged by carbamylated Lys217. To assess whether carbamate-specific chemistry is required for urease a...

  • The crystal structure of urease from Klebsiella aerogenes
    Science (New York N.Y.), 1995
    Co-Authors: Evelyn Jabri, Robert P. Hausinger, M. B. Carr, P.a. Karplus
    Abstract:

    The crystal structure of urease from Klebsiella aerogenes has been determined at 2.2 A resolution and refined to an R factor of 18.2 percent. The enzyme contains four structural domains: three with novel folds playing structural roles, and an (alpha beta)8 barrel domain, which contains the bi-nickel center. The two active site nickels are 3.5 A apart. One nickel ion is coordinated by three ligands (with low occupancy of a fourth ligand) and the second is coordinated by five ligands. A carbamylated lysine provides an oxygen ligand to each nickel, explaining why carbon dioxide is required for the activation of urease apoenzyme. The structure is compatible with a catalytic mechanism whereby urea ligates Ni-1 to complete its tetrahedral coordination and a hydroxide ligand of Ni-2 attacks the carbonyl carbon. A surprisingly high structural similarity between the urease catalytic domain and that of the zinc-dependent adenosine deaminase reveals a remarkable example of active site divergence.

M.a. Pearson - One of the best experts on this subject based on the ideXlab platform.

P.a. Karplus - One of the best experts on this subject based on the ideXlab platform.

  • Chemical Rescue of Klebsiella aerogenes Urease Variants Lacking the Carbamylated-Lysine Nickel Ligand†,‡
    Biochemistry, 1998
    Co-Authors: M.a. Pearson, R.a. Schaller, L.o. Michel, P.a. Karplus, Robert P. Hausinger
    Abstract:

    Klebsiella aerogenes urease possesses a dinuclear metallocenter in which two nickel atoms are bridged by carbamylated Lys217. To assess whether carbamate-specific chemistry is required for urease a...

  • chemical rescue of Klebsiella aerogenes urease variants lacking the carbamylated lysine nickel ligand
    Biochemistry, 1998
    Co-Authors: M.a. Pearson, R.a. Schaller, L.o. Michel, P.a. Karplus, Robert P. Hausinger
    Abstract:

    Klebsiella aerogenes urease possesses a dinuclear metallocenter in which two nickel atoms are bridged by carbamylated Lys217. To assess whether carbamate-specific chemistry is required for urease a...

  • The crystal structure of urease from Klebsiella aerogenes
    Science (New York N.Y.), 1995
    Co-Authors: Evelyn Jabri, Robert P. Hausinger, M. B. Carr, P.a. Karplus
    Abstract:

    The crystal structure of urease from Klebsiella aerogenes has been determined at 2.2 A resolution and refined to an R factor of 18.2 percent. The enzyme contains four structural domains: three with novel folds playing structural roles, and an (alpha beta)8 barrel domain, which contains the bi-nickel center. The two active site nickels are 3.5 A apart. One nickel ion is coordinated by three ligands (with low occupancy of a fourth ligand) and the second is coordinated by five ligands. A carbamylated lysine provides an oxygen ligand to each nickel, explaining why carbon dioxide is required for the activation of urease apoenzyme. The structure is compatible with a catalytic mechanism whereby urea ligates Ni-1 to complete its tetrahedral coordination and a hydroxide ligand of Ni-2 attacks the carbonyl carbon. A surprisingly high structural similarity between the urease catalytic domain and that of the zinc-dependent adenosine deaminase reveals a remarkable example of active site divergence.

R.a. Schaller - One of the best experts on this subject based on the ideXlab platform.

L.o. Michel - One of the best experts on this subject based on the ideXlab platform.