TitlePeptidomic analysis reveals proteolytic activity of kefir microorganisms on bovine milk proteins.
Publication TypeJournal Article
Year of Publication2016
AuthorsDallas, DC, Citerne, F, Tian, T, Silva, VLM, Kalanetra, KM, Frese, SA, Robinson, RC, Mills, DA, Barile, D
JournalFood Chem
Volume197
IssuePt A
Pagination273-84
Date Published2016 Apr 15
ISSN0308-8146
KeywordsAnimals, Cattle, Cultured Milk Products, DNA, Bacterial, Hydrogen-Ion Concentration, Lactobacillus, Milk Proteins, Proteolysis, RNA, Ribosomal, 16S, Sequence Alignment, Sequence Analysis, DNA
Abstract
 

SCOPE: The microorganisms that make up kefir grains are well known for lactose fermentation, but the extent to which they hydrolyze and consume milk proteins remains poorly understood. Peptidomics technologies were used to examine the proteolytic activity of kefir grains on bovine milk proteins.

METHODS AND RESULTS: Gel electrophoresis revealed substantial digestion of milk proteins by kefir grains, with mass spectrometric analysis showing the release of 609 protein fragments and alteration of the abundance of >1500 peptides that derived from 27 milk proteins. Kefir contained 25 peptides identified from the literature as having biological activity, including those with antihypertensive, antimicrobial, immunomodulatory, opioid and anti-oxidative functions. 16S rRNA and shotgun metagenomic sequencing identified the principle taxa in the culture as Lactobacillus species.

CONCLUSION: The model kefir sample contained thousands of protein fragments released in part by kefir microorganisms and in part by native milk proteases.

DOI10.1016/j.foodchem.2015.10.116
Alternate JournalFood Chem
PubMed ID26616950
PubMed Central IDPMC4664887
Grant ListK99 HD079561 / HD / NICHD NIH HHS / United States
R01AT008759 / AT / NCCIH NIH HHS / United States
S10RR029668 / RR / NCRR NIH HHS / United States
S10RR027303 / RR / NCRR NIH HHS / United States
S10 RR029668 / RR / NCRR NIH HHS / United States
K99HD079561 / HD / NICHD NIH HHS / United States
S10 RR027303 / RR / NCRR NIH HHS / United States
R00 HD079561 / HD / NICHD NIH HHS / United States
F32AT008533 / AT / NCCIH NIH HHS / United States
R01AT007079 / AT / NCCIH NIH HHS / United States
F32 AT008533 / AT / NCCIH NIH HHS / United States
R01 AT008759 / AT / NCCIH NIH HHS / United States
R01 AT007079 / AT / NCCIH NIH HHS / United States