Hi, Thanks for the quick reply!
This command removed protein_ID, but the other rows that do not contain locus_tag keept as they are.
To elaborate more, the output was like that
>Feature gnl|XXX|IFEJKLFI_1 gnl|XXX|IFEJKLFI_1
locus_tag IFEJKLFI_00001 IFEJKLFI_00001
locus_tag IFEJKLFI_00001 IFEJKLFI_00001
locus_tag IFEJKLFI_00002 IFEJKLFI_00002
locus_tag IFEJKLFI_00002 IFEJKLFI_00002
locus_tag IFEJKLFI_00419 IFEJKLFI_00419
locus_tag IFEJKLFI_00419 IFEJKLFI_00419
>Feature gnl|XXX|IFEJKLFI_2 gnl|XXX|IFEJKLFI_2
locus_tag IFEJKLFI_00423 IFEJKLFI_00423
locus_tag IFEJKLFI_00423 IFEJKLFI_00423
>Feature gnl|XXX|IFEJKLFI_3 gnl|XXX|IFEJKLFI_3
>Feature gnl|XXX|IFEJKLFI_4 gnl|XXX|IFEJKLFI_4
>Feature gnl|XXX|IFEJKLFI_5 gnl|XXX|IFEJKLFI_5
I need to remove the other >Feature lines that do not contain locus_tag.