<Tr> <Th> TCDB </Th> <Td> 3. E. 2 </Td> </Tr> <Tr> <Td_colspan="2"> <Table> <Tr> <Th_colspan="2"> (show) Available protein structures: </Th> </Tr> <Tr> <Th> Pfam </Th> <Td> structures </Td> </Tr> <Tr> <Th> PDB </Th> <Td> RCSB PDB; PDBe; PDBj </Td> </Tr> <Tr> <Th> PDBsum </Th> <Td> structure summary </Td> </Tr> </Table> </Td> </Tr> <Table> <Tr> <Th_colspan="2"> (show) Available protein structures: </Th> </Tr> <Tr> <Th> Pfam </Th> <Td> structures </Td> </Tr> <Tr> <Th> PDB </Th> <Td> RCSB PDB; PDBe; PDBj </Td> </Tr> <Tr> <Th> PDBsum </Th> <Td> structure summary </Td> </Tr> </Table> <Tr> <Th_colspan="2"> (show) Available protein structures: </Th> </Tr>

Where are the photosynthesis electron transfer system proteins located