Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_name_5 (accession_number VARCHAR, common_name VARCHAR)

### Question ###
What is the accession number of the protein with the common name Purple Sea Urchin?

### Accurate SQL ###

SELECT accession_number FROM table_name_5 WHERE common_name = "purple sea urchin"