Staphylococcus aureus 6 penicillin resistance 6 penicillinase 6 Bacteria (microorganisms) 4 Bacterial promoter 4 Bacteriophage promoter 4 DNA fragment 4 DNA sequence 4 Escherichia coli 4 Negibacteria 4 Posibacteria 4 Prokaryota 4 Promoter isolation 4 Strong promoter 4 Vector 4 ampicillin 4 antibiotic resistance 4 article 4 bacteriophage 4 bacteriophage a 4 nonhuman 4 nucleotide sequence 4 plasmid 4 plasmid vector 4 priority journal 4 promoter region 4 tetracycline 4 unidentified bacteriophage 4 Animals 2 Bovinae 2