| 别名 |
AAD, D-, D-dipeptidase, D-Ala-D-Ala amino dipeptidase, D-Ala-D-Ala dipeptidase, D-Ala-D-Ala dipeptidase VanX, D-Ala-D-Ala-dipeptidase, D-alanyl-D-alanine dipeptidase, M15.011, Vancomycin B-type resistance protein vanX, VanX, VanXY, VanXYc |
| Comments |
A Zn2+-dependent enzyme [4]. 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 [2,3]. The enzyme is stereospecific, as?L-Ala-L-Ala,?D-Ala-L-Ala and?L-Ala-D-Ala are not substrates [2]. Belongs in peptidase family?M15. |
