the beta-lactamase gene from four kinds of ampicillin transposons , tn2601 , tn3 , tn2602 and tn1 , specifying the type i ( or tem type , alternatively ) beta-lactamase was cloned onto plasmid pacyc184 , and the level of in vivo transcription from each beta-lactamase gene was determined by dna-rna hybridization .
C0040649
transcription
C0035668
rna