DPEP3
DPEP3 (dipeptidase 3) is a membrane-bound glycoprotein of the M19 metallopeptidase group, encoded by a gene on chromosome 16. Although it belongs to the dipeptidase family, UniProt annotates the human protein as lacking dipeptidase activity. Browse Assay Genie's current range of DPEP3 research reagents below, or read on for the biology behind the target.
DPEP3 is a member of the peptidase M19 family within the metallo-dependent hydrolases superfamily. The NCBI Gene summary describes the DPEP3 gene as encoding a membrane-bound glycoprotein from a family of dipeptidases involved in the hydrolytic metabolism of various dipeptides, including penem and carbapenem beta-lactam antibiotics. UniProt, however, annotates the protein as lacking dipeptidase activity: it is unable to hydrolyse cystinyl-bis-glycine, leukotriene D4 or the beta-lactam antibiotic imipenem.
The UniProt entry offers a structural explanation for this. Position 359 carries asparagine instead of the aspartate found in DPEP1 and DPEP2, and this residue may be unable to act as the acid/base catalyst that activates the nucleophilic water or hydroxide. Position 269 carries tyrosine instead of histidine, which reduces affinity for the beta zinc and may cause substrate steric hindrance. These differences make DPEP3 a useful point of comparison with its catalytically active relatives.
The human protein is 488 amino acids long and is classified by HGNC in the M19 metallopeptidases gene group. The gene sits on chromosome 16 in a cluster with another member of the dipeptidase family, and alternatively spliced transcript variants encoding different isoforms have been reported. Mouse and rat both have a Dpep3 ortholog, which allows comparative work across species.
DPEP3 lacks activity seen in related dipeptidases, so it is a natural reference for studying how M19 family members differ in function.
Substitutions at positions 359 and 269 are proposed to explain the absent catalytic activity, making DPEP3 relevant to metallopeptidase mechanism research.
As a membrane-bound glycoprotein, DPEP3 is of interest for studies of membrane-associated dipeptidase-like proteins and their cellular roles.
The dipeptidase family is linked to hydrolysis of penem and carbapenem antibiotics, and DPEP3 serves as an inactive comparator in this context.
According to UniProt, no. DPEP3 lacks dipeptidase activity and cannot hydrolyse cystinyl-bis-glycine, leukotriene D4 or imipenem. The likely reason is that asparagine at position 359, in place of aspartate, cannot act as the acid/base catalyst, and tyrosine at position 269 reduces affinity for the beta zinc.
DPEP3 is the HGNC symbol for dipeptidase 3, a membrane-bound glycoprotein of the peptidase M19 family. No alternative aliases or previous symbols are listed. The NCBI Gene summary notes that alternatively spliced transcript variants encoding different isoforms have been found.
DPEP3 shares the M19 family fold with DPEP1 and DPEP2 and is located in a gene cluster with another family member on chromosome 16. It differs at key catalytic positions. Mouse and rat each have a Dpep3 ortholog; check the datasheet of any product for its validated reactivity.
Other dipeptidases of the M19 metallopeptidase family with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt Q9H4B8; product specifications from Assay Genie datasheets.