Improving the Catalytic Activity of Hyperthermophilic <i>Pyrococcus horikoshii</i> Prolidase for Detoxification of Organophosphorus Nerve Agents over a Broad Range of Temperatures

<table class="table-group" id="tab2"><tr><td><table class="table"><tr><td class="thead-hr" colspan="5"><hr/></td></tr><tr class="thead"><td align="left">      Prolidase</td><td align="center"><i>  K<sub>m  </sub> </i><br/> (mM)</td><td align="center"><svg height="14.35" id="M6" style="vertical-align:-3.22282pt" version="1.1" viewbox="0 0 32.224998 14.35" width="32.224998" xmlns="http://www.w3.org/2000/svg">
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<tspan style="font-size: 12.50px; " x="0" y="0">𝑉</tspan>
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<text transform="matrix(1,0,0,-1,-64.76,60.66)">
<tspan style="font-size: 8.75px; " x="0" y="0">m</tspan>
<tspan style="font-size: 8.75px; " x="6.8090558" y="0">a</tspan>
<tspan style="font-size: 8.75px; " x="10.694944" y="0">x</tspan>
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</svg><br/> (<i>μ</i>mol/min/mg)</td><td align="center"><svg height="14.5875" id="M7" style="vertical-align:-3.22281pt" version="1.1" viewbox="0 0 21.975 14.5875" width="21.975" xmlns="http://www.w3.org/2000/svg">
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<g transform="translate(72,-60.33)">
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<tspan style="font-size: 8.75px; " x="0" y="0">c</tspan>
<tspan style="font-size: 8.75px; " x="3.8858881" y="0">a</tspan>
<tspan style="font-size: 8.75px; " x="7.7717762" y="0">t</tspan>
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</svg><br/> (s<sup>−1</sup>)</td><td align="center"><svg height="14.5875" id="M8" style="vertical-align:-3.22281pt" version="1.1" viewbox="0 0 21.975 14.5875" width="21.975" xmlns="http://www.w3.org/2000/svg">
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<g transform="translate(72,-60.33)">
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<tspan style="font-size: 12.50px; " x="0" y="0">𝑘</tspan>
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<tspan style="font-size: 8.75px; " x="0" y="0">c</tspan>
<tspan style="font-size: 8.75px; " x="3.8858881" y="0">a</tspan>
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</svg><i>/K<sub>m  </sub> </i><br/> (mM<sup>−1</sup>s<sup>−1</sup>)</td></tr><tr><td class="thead-hr" colspan="5"><hr/></td></tr><tr><td align="left">  WT-<i>Ph1</i>prol</td><td align="center">  0.92 ± 0.16</td><td align="center">  809 ± 55</td><td align="center">  1079</td><td align="center">  1172</td></tr><tr><td align="left">A195T/G306S</td><td align="center">0.81 ± 0.26</td><td align="center">1245 ± 149</td><td align="center">1660</td><td align="center">2049</td></tr><tr><td align="left">Y301C/K342N</td><td align="center"> 2.92 ± 0.40</td><td align="center">2146 ± 177</td><td align="center">2861</td><td align="center">980</td></tr><tr><td align="left">E127G/E252D</td><td align="center">0.98 ± 0.24</td><td align="center">1119 ± 101</td><td align="center">1492</td><td align="center">1522</td></tr><tr><td align="left">E36V</td><td align="center">1.6 ± 0.37</td><td align="center">1597 ± 174</td><td align="center">2129</td><td align="center">1331</td></tr><tr class="table-tr"><td colspan="5"><hr class="tbody-hr"/></td></tr></table></td></tr><tr class="table-fn"><td>Enzyme assays were done using a range of Leu-Pro concentrations (0.25–12 mM). Enzyme kinetics were calculated using nonlinear regression (curve fit) and analyzed using the Michaelis-Menten equation utilizing software from Prism 5 (GraphPad La Jolla, CA). All <i>Ph1</i>prol assays contained 0.2 mM CoCl<sub>2</sub>.<br/></td></tr></table>

Kinetic parameters of wild type <i>Pyrococcus horikoshii</i> prolidase, <i>Ph1</i>prol, and prolidase variants with Leu-Pro at 70°C.

Archaea

tab2

Table 2

Table 2: Improving the Catalytic Activity of Hyperthermophilic <i>Pyrococcus horikoshii</i> Prolidase for Detoxification of Organophosphorus Nerve Agents over a Broad Range of Temperatures 

Table 2 | Improving the Catalytic Activity of Hyperthermophilic Pyrococcus horikoshii Prolidase for Detoxification of Organophosphorus Nerve Agents over a Broad Range of Temperatures 