Oxamycin - Cycloserine

Another enzyme-activated inhibitor is the streptomyces antibiotic D-cycloserine (oxamycin), an antitubercular drug that resembles D-alanine in structure. A potent inhibitor of alanine racemase, it also inhibits die non-PLP, ATP-dependent, D-alanyl-D-alanine synthetase which is needed in the biosynthesis of die peptidoglycan of bacterial cell walls. 

A few antibiotics that are produced by Streptomyces spp. have structural affinities to single amino acids. Thus D-cycloserine (oxamycin), which has the structure XXVIII, could formally be obtained from D-serine amide by removal of the elements of water, or from D-alanine by an oxidative process. 

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