Journal:JBIC:10

Structures of the all cysteinyl coordinated D14C variant of ferredoxin from the hyperthermophilic archaeon ''Pyrococcus furiosus'' have been determined for the <scene name='Journal:JBIC:10/Cv1/5'>[4Fe-4S]</scene> <-> and <scene name='Journal:JBIC:10/Cv1/6'>[3Fe-4S]</scene> forms (<scene name='Journal:JBIC:10/Cv1/8'>click to enlarge</scene>). The [4Fe-4S] form diffracted to 1.7 Å and two different types of molecules were found in the crystal ([[2z8q]]). They have different crystal packing and intramolecular disulfide bond conformation. The crystal packing reveals a <scene name='Journal:JBIC:10/Cv/5'>beta-sheet interaction between A molecules</scene> (shown in <font color='blue'><b>blue</b></font> and <span style="color:green;background-color:black;font-weight:bold;">green</span>) in adjacent asymmetric units, while <scene name='Journal:JBIC:10/Cv/6'>B molecules are packed as monomers in a less rigid position next to the A-A extended beta-sheet dimers</scene> (shown in <font color='red'><b>red</b></font> and <span style="color:yellow;background-color:black;font-weight:bold;">yellow</span>). The <scene name='Journal:JBIC:10/Cv1/9'>intramolecular disulfide bond in the A molecules is in a double conformation</scene> while the intramolecular disulfide bond in the <scene name='Journal:JBIC:10/Cv1/10'>B molecules is in a single conformation</scene> (<scene name='Journal:JBIC:10/Cv1/11'>click to see morph</scene>, molecule A is shown in <font color='blue'><b>blue</b></font> and molecule B in <span style="color:green;background-color:black;font-weight:bold;">green</span>).

Structures of the all cysteinyl coordinated D14C variant of ferredoxin from the hyperthermophilic archaeon ''Pyrococcus furiosus'' have been determined for the <scene name='Journal:JBIC:10/Cv1/5'>[4Fe-4S]</scene> <-> and <scene name='Journal:JBIC:10/Cv1/6'>[3Fe-4S]</scene> forms (<scene name='Journal:JBIC:10/Cv1/8'>click to enlarge</scene>). The [4Fe-4S] form diffracted to 1.7 Å and two different types of molecules were found in the crystal ([[2z8q]]). They have different crystal packing and intramolecular disulfide bond conformation. The crystal packing reveals a <scene name='Journal:JBIC:10/Cv/5'>beta-sheet interaction between A molecules</scene> (shown in <font color='blue'><b>blue</b></font> and <span style="color:green;background-color:black;font-weight:bold;">green</span>) in adjacent asymmetric units, while <scene name='Journal:JBIC:10/Cv/6'>B molecules are packed as monomers in a less rigid position next to the A-A extended beta-sheet dimers</scene> (shown in <font color='red'><b>red</b></font> and <span style="color:yellow;background-color:black;font-weight:bold;">yellow</span>). The <scene name='Journal:JBIC:10/Cv1/9'>intramolecular disulfide bond in the A molecules is in a double conformation</scene> while the intramolecular disulfide bond in the <scene name='Journal:JBIC:10/Cv1/10'>B molecules is in a single conformation</scene> (<scene name='Journal:JBIC:10/Cv1/11'>click to see morph</scene>, molecule A is shown in <font color='blue'><b>blue</b></font> and molecule B in <span style="color:green;background-color:black;font-weight:bold;">green</span>).

Two forms of D14C [3Fe-4S] ''Pyrococcus furiosus'' ferredoxin are obtained when purified at pH 8.0: a monomer and a dimer connected by an intermolecular disulfide bond (see static image at the left). When purified at pH 5.8, only the monomer is obtained. The [3Fe-4S] form diffracted to 2.8 Å resolution and showed only the <scene name='Journal:JBIC:10/Cv1/13'>monomeric form, which resembles molecule A of D14C [4Fe-4S] Pyrococcus furiosus ferredoxin</scene>. Crystal packing in <scene name='Journal:JBIC:10/Cv2/7'>D14C [3Fe-4S] ferredoxin is as extended beta-sheet dimers of adjacent molecules</scene> (shown in <font color='red'><b>red</b></font> and <font color='orange'><b>orange</b></font>), which is the same as <scene name='Journal:JBIC:10/Cv2/9'>WT [3Fe-4S] P. furiosus ferredoxin</scene> ([[1sj1]], shown in <font color='blue'><b>blue</b></font> and <font color='cyan'><b>cyan</b></font>) even though the space groups are different (see also corresponding side views for <scene name='Journal:JBIC:10/Cv2/8'>D14C [3Fe-4S]</scene>) and <scene name='Journal:JBIC:10/Cv2/10'>WT [3Fe-4S]</scene>).

Two forms of D14C [3Fe-4S] ''Pyrococcus furiosus'' ferredoxin are obtained when purified at pH 8.0: a monomer and a dimer connected by an intermolecular disulfide bond (see static image at the left). When purified at pH 5.8, only the monomer is obtained. The [3Fe-4S] form diffracted to 2.8 Å resolution and showed only the <scene name='Journal:JBIC:10/Cv1/13'>monomeric form, which resembles molecule A of D14C [4Fe-4S] Pyrococcus furiosus ferredoxin</scene>. Crystal packing in <scene name='Journal:JBIC:10/Cv2/7'>D14C [3Fe-4S] ferredoxin is as extended beta-sheet dimers of adjacent molecules</scene> (shown in <font color='red'><b>red</b></font> and <font color='orange'><b>orange</b></font>), which is the same as <scene name='Journal:JBIC:10/Cv2/9'>WT [3Fe-4S] P. furiosus ferredoxin</scene> ([[1sj1]], shown in <font color='blue'><b>blue</b></font> and <font color='cyan'><b>cyan</b></font>) even though the space groups are different (see also corresponding side views for <scene name='Journal:JBIC:10/Cv2/8'>D14C [3Fe-4S]</scene>) and <scene name='Journal:JBIC:10/Cv2/10'>WT [3Fe-4S]</scene>).