D-Ala-D-Ala dipeptidase

A Zn2+-dependent enzyme. The enzyme protects Enterococcus faecium from the antibiotic vancomycin, which can bind to the -D-Ala-D-Ala sequence at the C-terminus of the peptidoglycan pentapeptide (see diagram). This enzyme reduces the availability of the free dipeptide D-Ala-D-Ala, which is the precursor for this pentapeptide sequence, allowing D-Ala-(R)-lactate (for which vancomycin has much less affinity)to be added to the cell wall instead. The enzyme is stereospecific, as L-Ala-L-Ala, D-Ala-L-Ala and L-Ala-D-Ala are not substrates. Belongs in peptidase family M15.

• Supplier: Creative Enzymes
• Product #: EXWM-4036