A protein that binds one of these compounds is engineered from a Tn10 gene product and the VP16 transactivator domain in a common inducible gene expression system. One type of these compounds forms the substrate of zinc-containing metalloenzymes that are class B in a classification scheme named for Ambler. A solution containing tryptone and yeast solution is commonly supplemented with these compounds (-5[1])to check for uptake (-5[1])of pUC19 or other vectors. One of these (-5[1])compounds (-5[1])prevents crosslinking (10[2])of N-acetylglucosamine (10[1]-5[1])and (10[1]-5[1])N-acetylmuramic (10[1])acid (10[2])and contains a characteristic four-atom ring. (10[1]-5[2])That type of these compounds, (10[1]-5[1])beta-lactams, (10[7]-5[1])disrupt (10[2])the (10[1])peptidoglycan (10[1])layer (10[1])of the cell (10[1])wall. For 10 points, (-5[1])penicillin (10[3])is what kind (10[1])of (10[3])drug (10[5])that kills bacteria? (10[3])■END■ (10[11])