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N-terminal Edman sequencing service

We provide
The N-terminal Edman sequencing service is applied to protein and peptide samples delivered lyophilzed, in solution or bound to PVDF membrane. Depending on sample amount typically 5 to 40 residues can be determined by N-terminal sequencing.

You receive
A final result report of N-terminal sequence analysis will be send by email or provided via SSL-server as a PDF file containing the amino acid sequence information and all HPLC chromatograms.

How to order
Please, contact us and ship the sample together with our Edman sequencing form signed by you. Below information are provided about sample requirements and shipping.

N-terminal protein/peptide sequencing prices

N-terminal protein/peptide sequencing services	Net Prices (excluding VAT)
Set-up / Minimum price (e.g. no sequence obtained due to N-terminal block)	EURO 100 US$ 133
N-terminal sequencing of 5 steps with set-up	EURO 200 US$ 265
Each additonal step	EURO 40 US$ 53
Volume discount for 10 and more samples	10%
One week service (Analysis will be performed within one week, on request)	add 50%

Sample requirements

Sample amount	20-100 pmols is preferred, but lower amounts are acceptable on request
Sample form	1. Pure lyophilized protein/peptide sample. 2. Liquid protein/peptide sample: 10-100 µl of violatile solvents such as water, propanol, acetonitrile. The sample should be shipped in frozen state. 3. On PVDF membrane bloted protein sample. The sample should be as concentrated as possible on the PVDF membrane (size: about 3x6 mm or smaller). The protein bands can be stained by Ponceau S, Amindo black or Coomassie Blue.
Purity	The sample should be as pure as possible (>75-80% purity) containing one protein or peptide. Amino acids, primary amines, SDS, salt, buffers and other contaminants should be removed from sample since these contaminants affect Edman degradation reaction and PTH amino acid detection and contaminate the instrument.
Cysteine modification	Unmodified cysteine residue can not be detected by Edman degradation. Therefore the sample has to be modified before sample submission if you wish to identify cysteine. A procedure is descibed below.
N-terminal blockage	The protein or peptide can not be sequenced if the N-terminal amino acid is blocked. About 50% of all eukaryontic protein are blocked. On request we perform de-blocking procedures which require usually significant more sample amount.
Glycosylation and other modifications	Blank Edman cycles, reduced peak intensities or altered retention times may result for glycosylated and phosphorylated amino acids.

Recommendations for sample shipping

Fill Edman order form with information about the samples (e.g. sample name, sample type, MW, estimated protein amount, staining method) and the requested number of N-terminal sequencing steps, sign the form.
Inform us by email or phone that your sample will be shipped.
Seal your sample in a reaction tube by plastic wrap. PVDF protein samples can either be shipped as cut protein bands in reaction tube or as a membrane piece in plastic wrap with documentation about the protein band which should be analyzed.
Liquid samples should be shipped in a frozen state.
PVDF protein bands and lyophilized samples can usually be send at room temperature.
Ship the samples in a padded envelope or box together with the Edman order form.

Recommended semidry blotting protocol

For semidry blotting on PVDF membrane we recommend the following blotting conditions:

Blotting buffer: 50 mM borate, pH9.0 / 20% methanol (HPLC grade)
Blotting conditions: 1mA/cm2 PVDF membrane for 2-3 hours. 0.1% SDS can be added for protein bigger than 40 kDa