1BTU:
reference: Inhibition of elastase by N-sulfonylaryl beta-lactams: anatomy of a stable acyl-enzyme complex., Wilmouth RC, Westwood NJ, Anderson K, Brownlee W, Claridge TD, Clifton IJ, Pritchard GJ, Aplin RT, Schofield CJ, Biochemistry 1998 Dec 15;37(50):17506-13. PMID: 9860865

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