TABLE 2.
Phosphopantetheinylation of carrier proteins by PPTNs, detected by addition of a phosphopantetheinyl moiety (340 Da), using mass spectrometry
| Carrier protein | PPT | Expected molecular mass (Da) | Observed molecular mass (Da) | Observed molecular mass of pantetheinylated carrier protein (Da) | % Holo-carrier proteina |
|---|---|---|---|---|---|
| ArCPNp (glycolipid biosynthesis) | PPTNs | 15,751 | 15,749 | 16,089 | 100 |
| MPCP (microcystin biosynthesis, NRPS) | PPTNs | 21,978 | 21,980 | 22,320 | 100 |
| ACPNp (nostopeptolide biosynthesis, PKS) | PPTNs | 20,812 | 20,812 | 21,153 | 69 |
a
The percentage of holo-carrier protein was estimated by comparing holo-carrier protein abundance and apo-carrier protein abundance in mass spectra as previously described (31).