>4D2O_1|Chains A, B|PER-2 BETA-LACTAMASE|CITROBACTER FREUNDII (546) SAQSPLLKEQIETIVTGKKATVGVAVWGPDDLEPLLLNPFEKFPMQSVFKLHLAMLVLHQVDQGKLDLNQSVTVNRAAVLQNTWSPMMKDHQGDEFTVAVQQLLQYSVSHSDNVACDLLFELVGGPQALHAYIQSLGVKEAAVVANEAQMHADDQVQYQNWTSMKAAAQVLQKFEQKKQLSETSQALLWKWMVETTTGPQRLKGLLPAGTIVAHKTGTSGVRAGKTAATNDAGVIMLPDGRPLLVAVFVKDSAESERTNEAIIAQVAQAAYQFELKKLSAVSPD