TABLE 4.
d,d-Peptidase and d,d-carboxypeptidase activities in cytoplasmic and membrane extracts from Nonomuraea sp. ATCC 39727 and its recombinant strains grown in VSP medium
| Nonomuraea sp. strain genotype or plasmid | Enzyme activity (nmol min−1 mg−1)a |
|||
|---|---|---|---|---|
| Mean ± SD d,d-carboxypeptidase activityb |
Mean ± SD d,d-peptidase activityb |
|||
| Membrane | Cytoplasmic | Membrane | Cytoplasmic | |
| Wild type | 52 ± 3.4 | BDLc | 20 ± 2.6 | BDL |
| ΔvanYn | BDL | BDL | BDL | BDL |
| ΔvanYn-pRT802Yn | 82 ± 2.3 | BDL | 49 ± 3.5 | BDL |
| pSET152Yn | 65 ± 2.8 | BDL | 39 ± 3.9 | BDL |
| pRT802Yn | 85 ± 3.1 | BDL | 44 ± 2.7 | BDL |
| pIJ86Yn | 180 ± 4.2 | BDL | 88 ± 3.1 | BDL |
| pST30 | BDL | BDL | 18 ± 1.8 | 210 ± 4.6 |
a
Enzymatic activities were measured in the cytoplasmic and membrane fractions from strains grown in VSP medium for 72 h. The fractions were prepared as described in Materials and Methods. The results were obtained from a minimum of three independent bacterial extracts.
b
The hydrolysis of d-Ala from 10 mM d-Ala-d-Ala and 10 mM acetyl-l-Lys-d-Ala-d-Ala was determined by using a d-amino acid oxidase-peroxidase coupled assay (23).
c
BDL, below detection limit (5 nmol) of the spectrophotometric assay.