PURase homologues
Four protein sequences for enzymes with known activity against PUR served as queries for BLAST (blastp, version 2.10.0+) against the NCBI non-redundant (nr) protein database and the PDB 21. BLAST performance was improved by multithreading with GNU/Parallel (version 20170622-1) 22. The BLAST results were filtered by an E-value threshold of 10-10 and a minimal coverage of 50% to further update the LED.