Dataset Information

Human milk and gastric peptidomics

ABSTRACT: It is unclear to what degree protein degradation occurs in the infant stomach and whether peptides previously annotated for bioactivity are released. This study combined nanospray liquid chromatography separation with time of flight mass spectrometry, comprehensive structural libraries and informatics to interrogate milk of three human mothers and the gastric aspirates from their 4–12 day post-partum infants. Milk from the mothers contained almost two hundred distinct peptides, demonstrating enzymatic degradation of milk proteins beginning either during lactation or between milk collection and feeding. In the gastric samples, 649 milk peptides were identified, demonstrating that digestion continues in the infant stomach. The majority of peptides in both the intact milk and gastric samples were derived from β-casein. The numbers of peptides from β-casein, lactoferrin, α-lactalbumin, lactadherin, κ-casein, serum albumin, bile-salt associated lipase and xanthine dehydrogenase/oxidase were significantly higher in the gastric samples than the milk samples (p<0.05). Six hundred three peptides were significantly different in abundance between milk and gastric samples (p<0.05). Most of the identified peptides have previously identified biological activity. Gastric proteolysis occurs in the term infant in the first two weeks of life releasing biologically active milk peptides with immunomodulatory, antibacterial, and calcium-binding activity of clinical relevance to the proximal intestinal tract.

INSTRUMENT(S): 6520 Quadrupole Time-of-Flight LC/MS

ORGANISM(S): Homo Sapiens (human)

SUBMITTER: David Dallas

LAB HEAD: David Dallas

PROVIDER: PXD000688 | Pride | 2014-04-15

REPOSITORIES: Pride

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A peptidomic analysis of human milk digestion in the infant stomach reveals protein-specific degradation patterns.

Dallas David C DC Guerrero Andrés A Khaldi Nora N Borghese Robyn R Bhandari Aashish A Underwood Mark A MA Lebrilla Carlito B CB German J Bruce JB Barile Daniela D

The Journal of nutrition 20140403 6

In vitro digestion of isolated milk proteins results in milk peptides with a variety of actions. However, it remains unclear to what degree protein degradation occurs in vivo in the infant stomach and whether peptides previously annotated for bioactivity are released. This study combined nanospray LC separation with time-of-flight mass spectrometry, comprehensive structural libraries, and informatics to analyze milk from 3 human mothers and the gastric aspirates from their 4- to 12-d-old postpar ...[more]

PMID: 24699806

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	7006a.G_MSMS-10x_EL1.mgf	Mgf
	7006a.G_MSMS-10x_EL2.mgf	Mgf
	7006a.G_MSMS-10x_EL3.mgf	Mgf
	7006a.G_MSMS-10x_EL4.mgf	Mgf
	7006a.G_MSMS-10x_EL5.mgf	Mgf