= Solution
The bulky substituents of <ceftazidime> can hinder productive entry into the more restricted <TEM-1> <active site>. A wider entrance in <TEM-52> could accommodate this <substrate> and allow its <beta-lactam> ring to be hydrolyzed. \b[The prediction is reduced susceptibility of <TEM-52>-expressing <bacteria> compared with matched <TEM-1>-expressing <bacteria>.] This is a mechanistic prediction, not a quantitative conclusion from the <penicillin G> data: entry alone does not guarantee efficient catalytic chemistry for a different <substrate>. Test <ceftazidime> <hydrolysis> directly and measure its <minimum inhibitory concentration> in an otherwise matched bacterial background, controlling <enzyme> expression, growth, drug entry and other resistance mechanisms.
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