ampC

Existing Annotations Review

GO Term	Evidence	Action	Reason
GO:0008800 beta-lactamase activity	IEA GO_REF:0000120	ACCEPT	Summary: AmpC is definitively a class C beta-lactamase (EC 3.5.2.6) that catalyzes the hydrolysis of beta-lactam antibiotics. This is the core molecular function of the protein. UniProt confirms EC=3.5.2.6 and the catalytic activity. The deep research confirms AmpC belongs to Ambler class C beta-lactamases that hydrolyze penicillins and cephalosporins. Reason: This is the primary enzymatic function of AmpC. UniProt annotation, InterPro domain analysis (IPR058136 AmpC, IPR001586 Beta-lactam_class-C_AS), and literature all confirm this enzyme catalyzes beta-lactam hydrolysis. This term correctly represents the core molecular function. Supporting Evidence: file:PSEPK/ampC/ampC-deep-research-falcon.md AmpC belongs to Ambler class C beta-lactamases (EC 3.5.2.6) that hydrolyze the beta-lactam ring of penicillins and cephalosporins
GO:0016787 hydrolase activity	IEA GO_REF:0000043	ACCEPT	Summary: This is a parent term of GO:0008800 (beta-lactamase activity). While technically correct that AmpC has hydrolase activity, this annotation is redundant given the more specific beta-lactamase activity annotation. UniProt keyword mapping correctly identifies the hydrolase nature, but the more specific child term provides greater biological insight. Reason: This term is accurate but generic. AmpC is indeed a hydrolase - specifically hydrolyzing the amide bond in the beta-lactam ring. The UniProt entry includes the Hydrolase keyword. While GO:0008800 (beta-lactamase activity) is more informative, retaining this broader annotation provides correct categorization and is acceptable as a parent term annotation from IEA evidence.
GO:0017001 antibiotic catabolic process	IEA GO_REF:0000002	MODIFY	Summary: This term captures the biological process of AmpC - catabolism of antibiotics. However, GO:0030655 (beta-lactam antibiotic catabolic process) is a more specific child term that accurately reflects AmpC's substrate specificity. AmpC specifically catabolizes beta-lactam antibiotics (penicillins, cephalosporins, monobactams), not antibiotics in general. Reason: While AmpC does participate in antibiotic catabolism, it specifically catabolizes beta-lactam antibiotics. The more specific term GO:0030655 beta-lactam antibiotic catabolic process (defined as chemical reactions and pathways resulting in the breakdown of a beta-lactam antibiotic) precisely describes AmpC's biological process. Literature confirms substrate specificity for penicillins and cephalosporins. Proposed replacements: beta-lactam antibiotic catabolic process Supporting Evidence: file:PSEPK/ampC/ampC-deep-research-falcon.md Hydrolysis of beta-lactam bonds in penicillins, cephalosporins, and monobactams is the signature activity of class C enzymes, conferring resistance when produced at elevated levels
GO:0030288 outer membrane-bounded periplasmic space	IEA GO_REF:0000002	ACCEPT	Summary: Periplasmic localization is well-supported for AmpC. UniProt shows a signal peptide (residues 1-24) indicating secretion across the inner membrane. Deep research confirms AmpC is synthesized with an N-terminal signal peptide and localizes to the periplasm where it intercepts incoming beta-lactams, with mature protein size ~40 kDa after signal peptide cleavage. Reason: This cellular component annotation is correct. AmpC functions in the periplasm where it can hydrolyze beta-lactam antibiotics before they reach their targets (penicillin-binding proteins on the inner membrane). The signal peptide and periplasmic localization are essential for the resistance mechanism. This represents a core aspect of AmpC function. Supporting Evidence: file:PSEPK/ampC/ampC-deep-research-falcon.md AmpC is synthesized with an N-terminal signal peptide, exported across the inner membrane, and localized to the periplasm where it can intercept incoming beta-lactams; maturation yields a protein of ~40 kDa after signal peptide cleavage
GO:0046677 response to antibiotic	IEA GO_REF:0000120	ACCEPT	Summary: This annotation captures AmpC's role in the organism's response to antibiotics. AmpC expression is induced by beta-lactam antibiotics and environmental signals (like indole), and its activity directly confers resistance. This term captures the broader biological context of response to antibiotic stress, including the regulatory induction. While GO:0030655 more precisely describes the enzymatic function, this term appropriately captures the response/resistance phenotype. Reason: This annotation is legitimate for a beta-lactamase. AmpC expression is induced by beta-lactam antibiotics through the AmpR-muropeptide signaling pathway, and indole also induces ampC expression in P. putida KT2440. The enzyme directly responds to antibiotic exposure by increasing expression and activity. Retaining both GO:0030655 and this term provides complementary perspectives - one on the catabolic process and one on the response/resistance phenotype. Supporting Evidence: file:PSEPK/ampC/ampC-deep-research-falcon.md Exogenous indole elevates ampC expression and beta-lactamase activity and increases the proportion of ampicillin-resistant P. putida KT2440 cells