Obtaining all protein sequences with a particular domain architecture from Pfam I want to get the alignment of chain A of 1kf6 (PDB ID) from the pfam database here. This protein chain has two main domains (FAD_binding_2 and    Succ_DH_flav_C). In pfam there is a link to one of these domains and after clicking in one of the mentioned domains in the table below the page, another page comes at the top of which there is a link to architectures. 

For example, if we click on "FAD_binding_2" in the table, there are 220 architectures that have this domain and after clicking on that button (at the top of page), a page opens here. In this page 7471 sequences with the following architecture: FAD_binding_2, Succ_DH_flav_C, resembles most to my chain (because it has both FAD_binding_2 and Succ_DH_flav_C domains). 

If we want to see all 7471 sequences with that architecture we can click on the show button under that architecture and finally we can see all of that 7471 architecture resembling our chain A sequence. Down the page we can see other architectures that all have FAD_binding_2, but some of them do not have both FAD_binding_2 and Succ_DH_flav_C domains (or some of them have other extra domains that we are not interested in) and so we do not need their sequences and their alignments. 

When we want to get the alignment of full sequences at the left side of the page, we can see that we can just get the alignment of all 15696 sequences and it seems that there is no way to get the alignment of our favourite 7471 sequences. I would like to know if there is any way to get the alignment or at least the fasta file of our favourite 7471 sequences (which have both of our favourite domains not just one of them)?
An alternative way is using the Hmmer website, and do a hmmsearch with the Pfam accession, forex. (PF02910). Navigate to the domain tab and find the domain architecture that you are interested in and press view scores. That way, only the sequences you are interested in will be downloadable under the tab downloads. 

Step-by-Step guide:

1- Go to http://www.ebi.ac.uk/Tools/hmmer/

2- Search with hmmsearch http://www.ebi.ac.uk/Tools/hmmer/search/hmmsearch

3- Use Accession search and type in PF02910

4- Navigate to Domain

5- To the right side of 
9742 sequences with domain architecture: FAD_binding_2, Succ_DH_flav_C 

Press View scores.

6- It should show (Your results have been filtered) and Query matches (9742)

7- Navigate to Download and download the sequences in the format of interest. 

8- Repeat for domain architectures of interest. 

I hope you find this helpful.

Kind Regards,

Sara