TABLE 3.
Identification of polypeptides
| Banda | Approximate molecular mass (kDa) | Identificationb | De novo peptides supporting identificationc | N-terminal sequenced |
|---|---|---|---|---|
| A | >66 | No identification possible | ND | ND |
| B | >66 | Transketolase (Vibrio sp. strain MED222) | FDGPSSLVVFSR | ND |
| Transketolase (Vibrio fischeri ES114) | FPEIAAEFTR | |||
| C | 64 | Methanol dehydrogenase large subunit (MxaF) (Methylophaga sp. strain DMS010) | RFKVLEGAHASFVEK | ND |
| D | 64 | Methanol dehydrogenase large subunit | AVACCDVVNR | ND |
| (MxaF) (Methylophaga sp. strain DMS010) | LLTHPDR | |||
| NGIVYTLDR | ||||
| E | 62 | XoxF (methanol dehydrogenase large subunit- | PAVNWSNGVN(I/L)K | ND |
| like protein) | QPAAYSPR | |||
| GELLVAEK | ||||
| F | 50 | Putative selenium binding protein [Silicibacter pomeroyi DSS-3; Methylococcus capsulatus (Bath)] | YLWAGGLDTSK | DET(C?)MSPYMAKISGQe |
| G | 48 | No identification possible | ND | No data; peptide may be blocked N terminally |
| H | 24 | Alkyl hydroperoxide reductase C thiol specific | EINDLGIGR | STLINTEIKPFKTTAf |
Band as labeled in Fig. 5.
Identification based on hits with the in-house database (containing partial methanol dehydrogenase large subunit gene sequences of Methylophaga isolates) and BLASTp searches (using the “search for short nearly exact matches” option).
Amino acid sequences obtained by in-line electrospray ionization tandem mass spectrometry that supported the identification, single-letter amino acid code. ND, not determined.
N-terminal amino acid sequence (single-letter amino acid code). ND, not determined.
No amino acid was detected at position 4, which may be due to a cysteine residue at this position.
N-terminal sequence was obtained from a Western blot of a rerun of the sample on another 12.5% SDS-PAGE gel (result not shown).