6.3.3.4 H447A the mutant shows severely reduced turnover number compared to the wild type enzyme 728238 6.3.3.4 additional information disruption mutant, complete loss of clavulanic acid production, accumulation of N2-(carboxyethyl)-L-arginine, but no effect on synthesis of penicillin or cephamycin 639031 6.3.3.4 V446A the mutant shows reduced turnover number compared to the wild type enzyme 728238 6.3.3.4 V446G the mutant shows strongly reduced turnover number compared to the wild type enzyme 728238