text: user9142: I got a FASTA file from NCBI RefSeq.
  These proteins are annotated with IDs like this : protein_id=XP_019970915.1.
  What type of ID is this? I would like to have them converted in TrEMBL IDs in order to do, later, a GO term enrichment but I have to know where I am starting from.
  Thank you in advance
  
  user9098: I'm not sure I understand the question, but XP_019970915.1 is an 'NCBI Reference Sequence' ID for 'erythrocyte binding antigen-181' (https://www.ncbi.nlm.nih.gov/protein/XP_019970915.1/). If you look that protein up in UniProt you can find other identifiers/info and GO annotations etc (https://www.uniprot.org/uniprot/A0A151LVZ9). Does that answer your question?
  
original_text: 9142: <p>I got a FASTA file from NCBI RefSeq.
  These proteins are annotated with IDs like this : protein_id=XP_019970915.1.
  What type of ID is this? I would like to have them converted in TrEMBL IDs in order to do, later, a GO term enrichment but I have to know where I am starting from.
  Thank you in advance</p>
   9098: <p>I'm not sure I understand the question, but XP_019970915.1 is an 'NCBI Reference Sequence' ID for 'erythrocyte binding antigen-181' (<a href="https://www.ncbi.nlm.nih.gov/protein/XP_019970915.1/" rel="nofollow noreferrer">https://www.ncbi.nlm.nih.gov/protein/XP_019970915.1/</a>). If you look that protein up in UniProt you can find other identifiers/info and GO annotations etc (<a href="https://www.uniprot.org/uniprot/A0A151LVZ9" rel="nofollow noreferrer">https://www.uniprot.org/uniprot/A0A151LVZ9</a>). Does that answer your question?</p>
  