1. ATPase Site Architecture and Helicase Mechanism of an Archaeal MCM
Matthew J. Moreau, Adam T. McGeoch, Alan R. Lowe, Laura S. Itzhaki, Stephen D. Bell 
Molecular Cell 
Volume 28, Issue 2, Pages (October 2007)
DOI: /j.molcel
Copyright © 2007 Elsevier Inc. Terms and Conditions

2. Figure 1 Mutational Analysis of the Sso MCM AAA+ Domain
(A) The upper panel shows a diagram of the position of mutants generated; 2 μg of purified proteins are shown in the lower panel.
(B) Helicase assays containing the indicated wild-type or mutant MCM.
(C) ATPase activities of the indicated MCM species.
(D) Elution profile of 6 μM of the wild-type and mutant MCMs on a Superose 6 gel filtration column.
Molecular Cell  , DOI: ( /j.molcel )
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3. Figure 2 ATPase Complementation Studies of SsoMCM
(A) ATPase activity of mixtures containing 1 μM of the indicated mutants and either 1 μM of Walker A K346A (purple bars) or arginine finger R473A (blue bars) mutant MCM. Results are the average of at least three experiments.
(B) Schematic of the results of pairwise complementation assays between the mutant MCMs. (++) indicates recovery of greater than 75% of wild-type activity, (+) indicates recovery of between 40% and 75% wild-type activity, and (−) indicates less than 20% wild-type activity.
Molecular Cell  , DOI: ( /j.molcel )
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4. Figure 3 Sensor 2 Acts In trans
(A) Structures of a modeled dimer of BchI and a dimer of NtrC. Sensor-1 and sensor-2 residues of adjacent subunits are highlighted in orange and indicated.
(B) SDS-PAGE analysis of BMH-mediated crosslinking experiments with the indicated pairs of Cys-mutated MCMs.
Molecular Cell  , DOI: ( /j.molcel )
Copyright © 2007 Elsevier Inc. Terms and Conditions

5. Figure 4 Mutant Doping Studies
Mutant doping studies with Walker A (K346A), (A and D); sensor-2 (R560A) MCM, (B and D); and arginine Finger-alanine mutant (R473A), (C and D). The indicated mutants were mixed with wild-type Sso MCM and then assayed for ATPase (A–C) in the presence and absence of DNA or helicase (C), activities; error bars represent the standard deviation of the results. Simulations were performed as described in Experimental Procedures, and the closest fit is shown as a solid red line. In (C), the simulation was according to the “WT-mutant pairs stimulation” model (see Experimental Procedures) with a value of s = 3. In (D), the simulation is the “pairs” model with a value of p = 2. The exponential decrease that would be observed if a single mutant subunit abrogated the hexamer's helicase activity is shown in blue. Assays were performed between three and ten times.
Molecular Cell  , DOI: ( /j.molcel )
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6. Figure 5 Stimulation by Mutant MCMs
The indicated mutants were mixed with wild-type and then assayed for ATPase (A and C) in the presence and absence of DNA. The mutant-wild-type mixes were also tested for helicase (B and D) activities; error bars represent the standard deviation of the results. Simulations were performed as described in Experimental Procedures, and the closest fit is shown as a solid red line. In (B) and (C), the “WT-mutant pairs stimulation” model was employed with s = 3 and 4. In (D), the “WT-mutant stimulation” model was used with values of w = 2 and s = 13. In (E), the results of doping with either the Walker A (K346A)/arginine finger (R473E) or Walker A (K346A)/sensor-2 (R560A) double mutants are shown. The “pairs simulation” that best fit the individual Walker A and sensor-2 mutant doping experiments is shown in green. The exponential decrease that would be observed if a single mutant subunit abrogated the hexamer's helicase activity is shown in blue. All assays were performed at least three times.
Molecular Cell  , DOI: ( /j.molcel )
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7. Figure 6 Helicase Complementation Studies
(A) Mg2+-ATP was titrated into helicase assays over the concentration range 117μM–60 mM. Values are expressed relative to the maximal helicase activity detected (at 7.5 mM).
(B–F) The indicated mutant SsoMCMs were mixed in the indicated ratio and assayed for helicase activity at 1 μM—the activity of the mutant pairs is plotted relative to that of 1 μM wild-type SsoMCM. Error bars represent the standard deviation of the results.
Molecular Cell  , DOI: ( /j.molcel )
Copyright © 2007 Elsevier Inc. Terms and Conditions