Sandbox Reserved 494: Difference between revisions
From Proteopedia
Jump to navigationJump to search
No edit summary |
No edit summary |
||
| Line 15: | Line 15: | ||
==Reaction analysis of the catalytic sites== | ==Reaction analysis of the catalytic sites== | ||
The energy for ATP synthesis is provided from proton transport along the gradient of electrochemical potential of protons across membranes (△H). When the magnitude of △H is large, as in | The energy for ATP synthesis is provided from proton transport along the gradient of electrochemical potential of protons across membranes (△H). When the magnitude of △H is large, as in functional mitochondrial, downhill proton flow through F<sub>0</sub> causes rotation of the F<sub>0</sub> rotor and hence rotation of the γε-subunits of F<sub>1</sub>. The rotary motion of the γ alternates the structure of the β-subunit so the ATP is synthesized<ref>PMID: 12788493</ref>. | ||
Mutagenesis of catalyticsites of ATP synthase have proceeded extensively in the ''E. coli'' enzymes, somewhat less so in '''<FONT COLOR="#571B7e">''Saccharomyces cerevisiae''</FONT>''' and '''<FONT COLOR="#F535AA">''Bacillus'' PS3</FONT>''' , and to far lesser extent in other species. Almost without exception, detailed in vitro biochemical analyses of purified mutant enzymes have been limited to the ATP hydrolysis reaction. However, in both yeast and E. coli, growth tests on nonfermentable substrates provide sensitive if quantative assays of ATP synthesis in the cell. Ligands to the Mg<sup>2+</sup> cation have been studied in detail by mutagenesis and functional analysis <ref>PMID: 9425083 </ref>. | Mutagenesis of catalyticsites of ATP synthase have proceeded extensively in the ''E. coli'' enzymes, somewhat less so in '''<FONT COLOR="#571B7e">''Saccharomyces cerevisiae''</FONT>''' and '''<FONT COLOR="#F535AA">''Bacillus'' PS3</FONT>''' , and to far lesser extent in other species. Almost without exception, detailed in vitro biochemical analyses of purified mutant enzymes have been limited to the ATP hydrolysis reaction. However, in both yeast and E. coli, growth tests on nonfermentable substrates provide sensitive if quantative assays of ATP synthesis in the cell. Ligands to the Mg<sup>2+</sup> cation have been studied in detail by mutagenesis and functional analysis <ref>PMID: 9425083 </ref>. | ||
