Table 5.
Summary of enzymes identified by the different approaches
| Activity | Metagenome ¤ | Functional screening | Strain collection |
|---|---|---|---|
| α-Amylase |
17 |
3* |
59 |
| Protease |
- |
0 |
73 |
| Cellulase |
4 |
0 |
1 |
| β-Glucanase |
0 |
0 |
20 |
| β-Xylanase |
7 |
0 |
1 |
| β-Mannanase |
3 |
0 |
0 |
| β-Galactosidase |
15 |
2 |
25 |
| Phosphatase |
- |
1 |
102 |
| α-Galactosidase | 10 | N/A | 75 |
Number of putative enzyme encoding open reading frames (ORFs) in the BAC clone metagenome (metagenome), number of enzyme producing E. coli clones carrying the BAC library (functional screening), and number of enzyme producing native bacteria in the strain collection (strain collection).
¤: Identified enzymes in the metagenome belonged to the following GH families: α-amylase: GH13 + 57; α-galactosidase: GH4 + 27 + 57; β-galactosidase: GH1 + 2 + 42; cellulase: GH5 + 8; β-xylanase: GH5 + 8 + 30; β-mannanase: GH5. *: The three α-amylase positive clones carried inserts from the same genomic region.