<?xml version="1.0" encoding="UTF-8" ?>

<PDBx:datablock datablockName="3TM"
   xmlns:PDBx="http://pdbml.pdb.org/schema/pdbx-v50.xsd"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation="http://pdbml.pdb.org/schema/pdbx-v50.xsd pdbx-v50.xsd">

   <PDBx:chem_compCategory>
      <PDBx:chem_comp id="3TM">
         <PDBx:formula>Fe4 S4</PDBx:formula>
         <PDBx:formula_weight>351.640</PDBx:formula_weight>
         <PDBx:name>Oxidizided C-cluster</PDBx:name>
         <PDBx:pdbx_ambiguous_flag>N</PDBx:pdbx_ambiguous_flag>
         <PDBx:pdbx_comp_type>metal-containing ligand</PDBx:pdbx_comp_type>
         <PDBx:pdbx_ideal_coordinates_details>MetalCoord</PDBx:pdbx_ideal_coordinates_details>
         <PDBx:pdbx_ideal_coordinates_missing_flag>N</PDBx:pdbx_ideal_coordinates_missing_flag>
         <PDBx:pdbx_initial_date>2026-05-06</PDBx:pdbx_initial_date>
         <PDBx:pdbx_model_coordinates_db_code>6B6W</PDBx:pdbx_model_coordinates_db_code>
         <PDBx:pdbx_model_coordinates_missing_flag>N</PDBx:pdbx_model_coordinates_missing_flag>
         <PDBx:pdbx_modified_date>2026-08-07</PDBx:pdbx_modified_date>
         <PDBx:pdbx_processing_site>RCSB</PDBx:pdbx_processing_site>
         <PDBx:pdbx_release_status>REL</PDBx:pdbx_release_status>
         <PDBx:pdbx_type>HETAIN</PDBx:pdbx_type>
         <PDBx:three_letter_code>3TM</PDBx:three_letter_code>
         <PDBx:type>non-polymer</PDBx:type>
      </PDBx:chem_comp>
   </PDBx:chem_compCategory>
   <PDBx:chem_comp_atomCategory>
      <PDBx:chem_comp_atom atom_id="S1" comp_id="3TM">
         <PDBx:alt_atom_id>S1</PDBx:alt_atom_id>
         <PDBx:charge>-2</PDBx:charge>
         <PDBx:model_Cartn_x>26.373</PDBx:model_Cartn_x>
         <PDBx:model_Cartn_y>0.906</PDBx:model_Cartn_y>
         <PDBx:model_Cartn_z>7.607</PDBx:model_Cartn_z>
         <PDBx:pdbx_align>1</PDBx:pdbx_align>
         <PDBx:pdbx_aromatic_flag>N</PDBx:pdbx_aromatic_flag>
         <PDBx:pdbx_component_atom_id>S1</PDBx:pdbx_component_atom_id>
         <PDBx:pdbx_component_comp_id>3TM</PDBx:pdbx_component_comp_id>
         <PDBx:pdbx_leaving_atom_flag>N</PDBx:pdbx_leaving_atom_flag>
         <PDBx:pdbx_model_Cartn_x_ideal>26.383</PDBx:pdbx_model_Cartn_x_ideal>
         <PDBx:pdbx_model_Cartn_y_ideal>0.911</PDBx:pdbx_model_Cartn_y_ideal>
         <PDBx:pdbx_model_Cartn_z_ideal>7.549</PDBx:pdbx_model_Cartn_z_ideal>
         <PDBx:pdbx_ordinal>1</PDBx:pdbx_ordinal>
         <PDBx:pdbx_stereo_config>N</PDBx:pdbx_stereo_config>
         <PDBx:type_symbol>S</PDBx:type_symbol>
      </PDBx:chem_comp_atom>
      <PDBx:chem_comp_atom atom_id="S2" comp_id="3TM">
         <PDBx:alt_atom_id>S2</PDBx:alt_atom_id>
         <PDBx:charge>-2</PDBx:charge>
         <PDBx:model_Cartn_x>23.051</PDBx:model_Cartn_x>
         <PDBx:model_Cartn_y>1.258</PDBx:model_Cartn_y>
         <PDBx:model_Cartn_z>5.884</PDBx:model_Cartn_z>
         <PDBx:pdbx_align>1</PDBx:pdbx_align>
         <PDBx:pdbx_aromatic_flag>N</PDBx:pdbx_aromatic_flag>
         <PDBx:pdbx_component_atom_id>S2</PDBx:pdbx_component_atom_id>
         <PDBx:pdbx_component_comp_id>3TM</PDBx:pdbx_component_comp_id>
         <PDBx:pdbx_leaving_atom_flag>N</PDBx:pdbx_leaving_atom_flag>
         <PDBx:pdbx_model_Cartn_x_ideal>23.078</PDBx:pdbx_model_Cartn_x_ideal>
         <PDBx:pdbx_model_Cartn_y_ideal>1.227</PDBx:pdbx_model_Cartn_y_ideal>
         <PDBx:pdbx_model_Cartn_z_ideal>5.898</PDBx:pdbx_model_Cartn_z_ideal>
         <PDBx:pdbx_ordinal>2</PDBx:pdbx_ordinal>
         <PDBx:pdbx_stereo_config>N</PDBx:pdbx_stereo_config>
         <PDBx:type_symbol>S</PDBx:type_symbol>
      </PDBx:chem_comp_atom>
      <PDBx:chem_comp_atom atom_id="S3" comp_id="3TM">
         <PDBx:alt_atom_id>S3</PDBx:alt_atom_id>
         <PDBx:charge>-2</PDBx:charge>
         <PDBx:model_Cartn_x>23.960</PDBx:model_Cartn_x>
         <PDBx:model_Cartn_y>-1.964</PDBx:model_Cartn_y>
         <PDBx:model_Cartn_z>8.157</PDBx:model_Cartn_z>
         <PDBx:pdbx_align>1</PDBx:pdbx_align>
         <PDBx:pdbx_aromatic_flag>N</PDBx:pdbx_aromatic_flag>
         <PDBx:pdbx_component_atom_id>S3</PDBx:pdbx_component_atom_id>
         <PDBx:pdbx_component_comp_id>3TM</PDBx:pdbx_component_comp_id>
         <PDBx:pdbx_leaving_atom_flag>N</PDBx:pdbx_leaving_atom_flag>
         <PDBx:pdbx_model_Cartn_x_ideal>23.728</PDBx:pdbx_model_Cartn_x_ideal>
         <PDBx:pdbx_model_Cartn_y_ideal>-1.619</PDBx:pdbx_model_Cartn_y_ideal>
         <PDBx:pdbx_model_Cartn_z_ideal>8.198</PDBx:pdbx_model_Cartn_z_ideal>
         <PDBx:pdbx_ordinal>3</PDBx:pdbx_ordinal>
         <PDBx:pdbx_stereo_config>N</PDBx:pdbx_stereo_config>
         <PDBx:type_symbol>S</PDBx:type_symbol>
      </PDBx:chem_comp_atom>
      <PDBx:chem_comp_atom atom_id="S4" comp_id="3TM">
         <PDBx:alt_atom_id>S4</PDBx:alt_atom_id>
         <PDBx:charge>-2</PDBx:charge>
         <PDBx:model_Cartn_x>24.036</PDBx:model_Cartn_x>
         <PDBx:model_Cartn_y>3.849</PDBx:model_Cartn_y>
         <PDBx:model_Cartn_z>8.415</PDBx:model_Cartn_z>
         <PDBx:pdbx_align>1</PDBx:pdbx_align>
         <PDBx:pdbx_aromatic_flag>N</PDBx:pdbx_aromatic_flag>
         <PDBx:pdbx_component_atom_id>S4</PDBx:pdbx_component_atom_id>
         <PDBx:pdbx_component_comp_id>3TM</PDBx:pdbx_component_comp_id>
         <PDBx:pdbx_leaving_atom_flag>N</PDBx:pdbx_leaving_atom_flag>
         <PDBx:pdbx_model_Cartn_x_ideal>24.004</PDBx:pdbx_model_Cartn_x_ideal>
         <PDBx:pdbx_model_Cartn_y_ideal>3.605</PDBx:pdbx_model_Cartn_y_ideal>
         <PDBx:pdbx_model_Cartn_z_ideal>8.519</PDBx:pdbx_model_Cartn_z_ideal>
         <PDBx:pdbx_ordinal>4</PDBx:pdbx_ordinal>
         <PDBx:pdbx_stereo_config>N</PDBx:pdbx_stereo_config>
         <PDBx:type_symbol>S</PDBx:type_symbol>
      </PDBx:chem_comp_atom>
      <PDBx:chem_comp_atom atom_id="FE1" comp_id="3TM">
         <PDBx:alt_atom_id>FE1</PDBx:alt_atom_id>
         <PDBx:model_Cartn_x>22.360</PDBx:model_Cartn_x>
         <PDBx:model_Cartn_y>2.285</PDBx:model_Cartn_y>
         <PDBx:model_Cartn_z>7.870</PDBx:model_Cartn_z>
         <PDBx:pdbx_align>0</PDBx:pdbx_align>
         <PDBx:pdbx_aromatic_flag>N</PDBx:pdbx_aromatic_flag>
         <PDBx:pdbx_component_atom_id>FE1</PDBx:pdbx_component_atom_id>
         <PDBx:pdbx_component_comp_id>3TM</PDBx:pdbx_component_comp_id>
         <PDBx:pdbx_leaving_atom_flag>N</PDBx:pdbx_leaving_atom_flag>
         <PDBx:pdbx_model_Cartn_x_ideal>22.264</PDBx:pdbx_model_Cartn_x_ideal>
         <PDBx:pdbx_model_Cartn_y_ideal>2.171</PDBx:pdbx_model_Cartn_y_ideal>
         <PDBx:pdbx_model_Cartn_z_ideal>7.882</PDBx:pdbx_model_Cartn_z_ideal>
         <PDBx:pdbx_ordinal>5</PDBx:pdbx_ordinal>
         <PDBx:pdbx_stereo_config>N</PDBx:pdbx_stereo_config>
         <PDBx:type_symbol>FE</PDBx:type_symbol>
      </PDBx:chem_comp_atom>
      <PDBx:chem_comp_atom atom_id="FE2" comp_id="3TM">
         <PDBx:alt_atom_id>FE2</PDBx:alt_atom_id>
         <PDBx:model_Cartn_x>22.400</PDBx:model_Cartn_x>
         <PDBx:model_Cartn_y>-0.569</PDBx:model_Cartn_y>
         <PDBx:model_Cartn_z>9.174</PDBx:model_Cartn_z>
         <PDBx:pdbx_align>0</PDBx:pdbx_align>
         <PDBx:pdbx_aromatic_flag>N</PDBx:pdbx_aromatic_flag>
         <PDBx:pdbx_component_atom_id>FE2</PDBx:pdbx_component_atom_id>
         <PDBx:pdbx_component_comp_id>3TM</PDBx:pdbx_component_comp_id>
         <PDBx:pdbx_leaving_atom_flag>N</PDBx:pdbx_leaving_atom_flag>
         <PDBx:pdbx_model_Cartn_x_ideal>22.216</PDBx:pdbx_model_Cartn_x_ideal>
         <PDBx:pdbx_model_Cartn_y_ideal>-0.345</PDBx:pdbx_model_Cartn_y_ideal>
         <PDBx:pdbx_model_Cartn_z_ideal>9.430</PDBx:pdbx_model_Cartn_z_ideal>
         <PDBx:pdbx_ordinal>6</PDBx:pdbx_ordinal>
         <PDBx:pdbx_stereo_config>N</PDBx:pdbx_stereo_config>
         <PDBx:type_symbol>FE</PDBx:type_symbol>
      </PDBx:chem_comp_atom>
      <PDBx:chem_comp_atom atom_id="FE3" comp_id="3TM">
         <PDBx:alt_atom_id>FE3</PDBx:alt_atom_id>
         <PDBx:model_Cartn_x>24.820</PDBx:model_Cartn_x>
         <PDBx:model_Cartn_y>2.455</PDBx:model_Cartn_y>
         <PDBx:model_Cartn_z>6.815</PDBx:model_Cartn_z>
         <PDBx:pdbx_align>0</PDBx:pdbx_align>
         <PDBx:pdbx_aromatic_flag>N</PDBx:pdbx_aromatic_flag>
         <PDBx:pdbx_component_atom_id>FE3</PDBx:pdbx_component_atom_id>
         <PDBx:pdbx_component_comp_id>3TM</PDBx:pdbx_component_comp_id>
         <PDBx:pdbx_leaving_atom_flag>N</PDBx:pdbx_leaving_atom_flag>
         <PDBx:pdbx_model_Cartn_x_ideal>24.820</PDBx:pdbx_model_Cartn_x_ideal>
         <PDBx:pdbx_model_Cartn_y_ideal>2.382</PDBx:pdbx_model_Cartn_y_ideal>
         <PDBx:pdbx_model_Cartn_z_ideal>6.779</PDBx:pdbx_model_Cartn_z_ideal>
         <PDBx:pdbx_ordinal>7</PDBx:pdbx_ordinal>
         <PDBx:pdbx_stereo_config>N</PDBx:pdbx_stereo_config>
         <PDBx:type_symbol>FE</PDBx:type_symbol>
      </PDBx:chem_comp_atom>
      <PDBx:chem_comp_atom atom_id="FE4" comp_id="3TM">
         <PDBx:alt_atom_id>FE4</PDBx:alt_atom_id>
         <PDBx:model_Cartn_x>24.549</PDBx:model_Cartn_x>
         <PDBx:model_Cartn_y>-0.273</PDBx:model_Cartn_y>
         <PDBx:model_Cartn_z>6.718</PDBx:model_Cartn_z>
         <PDBx:pdbx_align>0</PDBx:pdbx_align>
         <PDBx:pdbx_aromatic_flag>N</PDBx:pdbx_aromatic_flag>
         <PDBx:pdbx_component_atom_id>FE4</PDBx:pdbx_component_atom_id>
         <PDBx:pdbx_component_comp_id>3TM</PDBx:pdbx_component_comp_id>
         <PDBx:pdbx_leaving_atom_flag>N</PDBx:pdbx_leaving_atom_flag>
         <PDBx:pdbx_model_Cartn_x_ideal>24.646</PDBx:pdbx_model_Cartn_x_ideal>
         <PDBx:pdbx_model_Cartn_y_ideal>-0.244</PDBx:pdbx_model_Cartn_y_ideal>
         <PDBx:pdbx_model_Cartn_z_ideal>6.627</PDBx:pdbx_model_Cartn_z_ideal>
         <PDBx:pdbx_ordinal>8</PDBx:pdbx_ordinal>
         <PDBx:pdbx_stereo_config>N</PDBx:pdbx_stereo_config>
         <PDBx:type_symbol>FE</PDBx:type_symbol>
      </PDBx:chem_comp_atom>
   </PDBx:chem_comp_atomCategory>
   <PDBx:chem_comp_bondCategory>
      <PDBx:chem_comp_bond atom_id_1="S1" atom_id_2="FE3" comp_id="3TM">
         <PDBx:pdbx_aromatic_flag>N</PDBx:pdbx_aromatic_flag>
         <PDBx:pdbx_ordinal>1</PDBx:pdbx_ordinal>
         <PDBx:pdbx_stereo_config>N</PDBx:pdbx_stereo_config>
         <PDBx:value_order>sing</PDBx:value_order>
      </PDBx:chem_comp_bond>
      <PDBx:chem_comp_bond atom_id_1="S1" atom_id_2="FE4" comp_id="3TM">
         <PDBx:pdbx_aromatic_flag>N</PDBx:pdbx_aromatic_flag>
         <PDBx:pdbx_ordinal>2</PDBx:pdbx_ordinal>
         <PDBx:pdbx_stereo_config>N</PDBx:pdbx_stereo_config>
         <PDBx:value_order>sing</PDBx:value_order>
      </PDBx:chem_comp_bond>
      <PDBx:chem_comp_bond atom_id_1="S2" atom_id_2="FE1" comp_id="3TM">
         <PDBx:pdbx_aromatic_flag>N</PDBx:pdbx_aromatic_flag>
         <PDBx:pdbx_ordinal>3</PDBx:pdbx_ordinal>
         <PDBx:pdbx_stereo_config>N</PDBx:pdbx_stereo_config>
         <PDBx:value_order>sing</PDBx:value_order>
      </PDBx:chem_comp_bond>
      <PDBx:chem_comp_bond atom_id_1="S2" atom_id_2="FE3" comp_id="3TM">
         <PDBx:pdbx_aromatic_flag>N</PDBx:pdbx_aromatic_flag>
         <PDBx:pdbx_ordinal>4</PDBx:pdbx_ordinal>
         <PDBx:pdbx_stereo_config>N</PDBx:pdbx_stereo_config>
         <PDBx:value_order>sing</PDBx:value_order>
      </PDBx:chem_comp_bond>
      <PDBx:chem_comp_bond atom_id_1="S2" atom_id_2="FE4" comp_id="3TM">
         <PDBx:pdbx_aromatic_flag>N</PDBx:pdbx_aromatic_flag>
         <PDBx:pdbx_ordinal>5</PDBx:pdbx_ordinal>
         <PDBx:pdbx_stereo_config>N</PDBx:pdbx_stereo_config>
         <PDBx:value_order>sing</PDBx:value_order>
      </PDBx:chem_comp_bond>
      <PDBx:chem_comp_bond atom_id_1="S3" atom_id_2="FE2" comp_id="3TM">
         <PDBx:pdbx_aromatic_flag>N</PDBx:pdbx_aromatic_flag>
         <PDBx:pdbx_ordinal>6</PDBx:pdbx_ordinal>
         <PDBx:pdbx_stereo_config>N</PDBx:pdbx_stereo_config>
         <PDBx:value_order>sing</PDBx:value_order>
      </PDBx:chem_comp_bond>
      <PDBx:chem_comp_bond atom_id_1="S3" atom_id_2="FE4" comp_id="3TM">
         <PDBx:pdbx_aromatic_flag>N</PDBx:pdbx_aromatic_flag>
         <PDBx:pdbx_ordinal>7</PDBx:pdbx_ordinal>
         <PDBx:pdbx_stereo_config>N</PDBx:pdbx_stereo_config>
         <PDBx:value_order>sing</PDBx:value_order>
      </PDBx:chem_comp_bond>
      <PDBx:chem_comp_bond atom_id_1="S4" atom_id_2="FE1" comp_id="3TM">
         <PDBx:pdbx_aromatic_flag>N</PDBx:pdbx_aromatic_flag>
         <PDBx:pdbx_ordinal>8</PDBx:pdbx_ordinal>
         <PDBx:pdbx_stereo_config>N</PDBx:pdbx_stereo_config>
         <PDBx:value_order>sing</PDBx:value_order>
      </PDBx:chem_comp_bond>
      <PDBx:chem_comp_bond atom_id_1="S4" atom_id_2="FE3" comp_id="3TM">
         <PDBx:pdbx_aromatic_flag>N</PDBx:pdbx_aromatic_flag>
         <PDBx:pdbx_ordinal>9</PDBx:pdbx_ordinal>
         <PDBx:pdbx_stereo_config>N</PDBx:pdbx_stereo_config>
         <PDBx:value_order>sing</PDBx:value_order>
      </PDBx:chem_comp_bond>
   </PDBx:chem_comp_bondCategory>
   <PDBx:pdbx_chem_comp_auditCategory>
      <PDBx:pdbx_chem_comp_audit action_type="Create component" comp_id="3TM" date="2026-05-06">
         <PDBx:processing_site>RCSB</PDBx:processing_site>
      </PDBx:pdbx_chem_comp_audit>
      <PDBx:pdbx_chem_comp_audit action_type="Other modification" comp_id="3TM" date="2026-07-31">
         <PDBx:processing_site>RCSB</PDBx:processing_site>
      </PDBx:pdbx_chem_comp_audit>
      <PDBx:pdbx_chem_comp_audit action_type="Initial release" comp_id="3TM" date="2026-08-12">
         <PDBx:processing_site>RCSB</PDBx:processing_site>
      </PDBx:pdbx_chem_comp_audit>
   </PDBx:pdbx_chem_comp_auditCategory>
   <PDBx:pdbx_chem_comp_descriptorCategory>
      <PDBx:pdbx_chem_comp_descriptor comp_id="3TM" program="InChI" program_version="1.06" type="InChI">
         <PDBx:descriptor>InChI=1S/4Fe.4S</PDBx:descriptor>
      </PDBx:pdbx_chem_comp_descriptor>
      <PDBx:pdbx_chem_comp_descriptor comp_id="3TM" program="InChI" program_version="1.06" type="InChIKey">
         <PDBx:descriptor>LJBDFODJNLIPKO-UHFFFAOYSA-N</PDBx:descriptor>
      </PDBx:pdbx_chem_comp_descriptor>
      <PDBx:pdbx_chem_comp_descriptor comp_id="3TM" program="CACTVS" program_version="3.385" type="SMILES_CANONICAL">
         <PDBx:descriptor>[Fe]S[Fe]1S[Fe]S[Fe]S1</PDBx:descriptor>
      </PDBx:pdbx_chem_comp_descriptor>
      <PDBx:pdbx_chem_comp_descriptor comp_id="3TM" program="CACTVS" program_version="3.385" type="SMILES">
         <PDBx:descriptor>[Fe]S[Fe]1S[Fe]S[Fe]S1</PDBx:descriptor>
      </PDBx:pdbx_chem_comp_descriptor>
      <PDBx:pdbx_chem_comp_descriptor comp_id="3TM" program="OpenEye OEToolkits" program_version="3.1.0.0" type="SMILES_CANONICAL">
         <PDBx:descriptor>S1[Fe][S]2[Fe]1S[Fe]2S[Fe]</PDBx:descriptor>
      </PDBx:pdbx_chem_comp_descriptor>
      <PDBx:pdbx_chem_comp_descriptor comp_id="3TM" program="OpenEye OEToolkits" program_version="3.1.0.0" type="SMILES">
         <PDBx:descriptor>S1[Fe][S]2[Fe]1S[Fe]2S[Fe]</PDBx:descriptor>
      </PDBx:pdbx_chem_comp_descriptor>
   </PDBx:pdbx_chem_comp_descriptorCategory>
   <PDBx:pdbx_chem_comp_identifierCategory>
      <PDBx:pdbx_chem_comp_identifier comp_id="3TM" program="OpenEye OEToolkits" program_version="3.1.0.0" type="SYSTEMATIC NAME">
         <PDBx:identifier>1$l^{3},3,5-trithia-2$l^{3},4$l^{3},6$l^{2}-triferrabicyclo[2.2.0]hexan-2-ylsulfanyliron</PDBx:identifier>
      </PDBx:pdbx_chem_comp_identifier>
   </PDBx:pdbx_chem_comp_identifierCategory>
</PDBx:datablock>
