Precise protein quantification based on peptide quantification using iTRAQ™

BMC Bioinformatics

Table 6 Quantification results of the sample 1:3 mix.

Protein Id	Protein name	Quant						EE	Mascot™ 2.2
								2.9306
		Ratio	n	IQR	RMS	LSE	μ	σ	Ratio	σ
P02769	Serum albumin precursor ALBU_BOVIN	0.9424	5	0.2392	0.0100	0.9742	-0.0407	0.1906	0.9810	1.1000
P00722	Beta-galactosidase BGAL_ECOLI	0.9674	13	0.2101	0.0113	0.9936	-0.0203	0.1687	0.9910	NN
P02787	Serotransferrin precursor TRFE_HUMAN	1.0511	22	0.3356	0.0168	1.0526	0.0332	0.1924	0.9810	NN

The quantification results of the sample 1:3 mix are shown that include all unique peptides of each identified protein. Listed are the Protein Id, the protein name, and the protein ratio (ratio) with the experiment error (EE) estimate of Quant. The number of MS/MS spectra is listed in column n. Several quality factors calculated by Quant are shown: the least squares estimator (LSE), interquartile range (IQR), root-mean-square value (RMS), mean value (μ) and standard deviation (σ). μ and σ of Quant results were calculated from the log-transformed data. For comparison, results of Mascot™ 2.2 are listed. The protein ratios of the results are normalized.

ISSN: 1471-2105