Dataset Information

Milk bottom-up proteomics: method optimisation.

ABSTRACT: Milk is a complex fluid whose proteome displays a diverse set of proteins of high abundance such as caseins and medium to low abundance whey proteins such as ß-lactoglobulin, lactoferrin, immunoglobulins, glycoproteins, peptide hormones and enzymes. A sample preparation method that enables high reproducibility and throughput is key in reliably identifying proteins present or proteins responding to conditions such as a diet, health or genetics. Using skim milk samples from Jersey and Holstein cows, we compared three extraction procedures which have not previously been applied to samples of cows’ milk. Method A (urea) involved a simple dilution of the milk in a urea-based buffer, method B (TCA/acetone) involved a TCA/acetone precipitation and method C (methanol/chloroform) involved a tri-phasic partition method in chloroform/methanol solution. Protein assays, SDS-PAGE profiling, and trypsin digestion followed by nanoHPLC-electrospray ionisation-tandem mass spectrometry (nLC-ESI-MS/MS) analyses were performed to assess their efficiency. Replicates were used at each analytical step (extraction, digestion, injection) to assess reproducibility. Overall 186 unique accessions, major and minor proteins, were identified with a combination of methods. Method C (methanol/chloroform) yielded the best resolved SDS-patterns and highest protein recovery rates, method A (urea) yielded the greatest number of accessions, and, of the three procedures, method B (TCA/acetone) was the least compatible of all with a wide range of downstream analytical procedures. Our results also highlighted breed differences between the proteins in milk of Jersey and Holstein cows.

INSTRUMENT(S): LTQ Orbitrap Velos

ORGANISM(S): Bos Taurus (bovine)

TISSUE(S): Milk

SUBMITTER: Delphine Vincent

LAB HEAD: Delphine Vincent

PROVIDER: PXD002529 | Pride | 2016-01-26

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	2014-11-19_1112-A1_1_1_rep1.msf	Msf
	2014-11-19_1112-A1_1_1_rep1.pep.xml	Pepxml
	2014-11-19_1112-A1_1_1_rep1.prot.xml	Xml
	2014-11-19_1112-A1_1_1_rep1.raw	Raw
	2014-11-19_1112-A1_1_1_rep2.msf	Msf

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Publications

Milk Bottom-Up Proteomics: Method Optimization.

Vincent Delphine D Ezernieks Vilnis V Elkins Aaron A Nguyen Nga N Moate Peter J PJ Cocks Benjamin G BG Rochfort Simone S

Frontiers in genetics 20160111

Milk is a complex fluid whose proteome displays a diverse set of proteins of high abundance such as caseins and medium to low abundance whey proteins such as ß-lactoglobulin, lactoferrin, immunoglobulins, glycoproteins, peptide hormones, and enzymes. A sample preparation method that enables high reproducibility and throughput is key in reliably identifying proteins present or proteins responding to conditions such as a diet, health or genetics. Using skim milk samples from Jersey and Holstein-Fr ...[more]

PMID: 26793233

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