Sentence: We found that MERS-CoV NS4b and homologs from related lineage C bat betacoronaviruses BtCoV-SC2013 ( SC2013 ) and BtCoV-HKU5 ( HKU5 ) are members of the 2H-phosphoesterase ( 2H-PE ) enzyme family with phosphodiesterase ( PDE ) activity. 
 Section: finding