In this task, you are given a sentence. You are expected to recognize the name of gene or protein. Although there might be several correct answers, you need to write one of them.

Example Input:  Recombinant caspases are typically produced in Escherichia coli expression systems with the attendant problems of solubilization , re - folding and activation of the protease .
Example Output: Recombinant caspases

Example Input:  The requirement for an essential interaction between NPH I and H4L provides an explanation for the observed restriction of transcription termination to early viral genes .
Example Output: NPH I

Example Input:  Sequence and deletion analysis of the recombination enhancement gene ( ref ) of bacteriophage P1 : evidence for promoter - operator and attenuator - antiterminator control .
Example Output:
recombination enhancement gene