When cells of Propionibacterium freudenreichii were incubated under fasting conditions and then plated in the presence of an inhibitor of protein synthesis, a variable but significant (greater than 10(-2) fraction of the population changed their morphology from rod to sphere, with a considerable thickening of the cell wall. This change was accompanied by metabolic and antibiotic-resistance modifications, including the synthesis of at least one new enzyme (alpha-glucosidase), and by the simultaneous appearance of several new species of DNA, presumably plasmids. The round cells grew faster than the parent strain and maintained their morphology indefinitely when propagated on complex medium containing glucose as the main carbon source. However, when glucose was omitted, cells returned to the rod form and regained their previous characteristics, including the absence of detectable plasmids.
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http://dx.doi.org/10.1099/00221287-134-2-283 | DOI Listing |
Foods
January 2025
Whole Grain Food Engineering Research Center, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
The in situ fortification of vitamin B12 (VB12) in foods through fermentation is an effective strategy to address the deficiency of this micronutrient, and precise monitoring of VB12 production is crucial for developing VB12-fortified functional foods. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is advantageous for analyzing trace substances in food due to its high sensitivity. In the present study, an LC-MS/MS method capable of rapidly and accurately quantifying three active forms of VB12, namely adenosylcobalamin (AdoCbl), methylcobalamin (MeCbl), hydroxocobalamin (OHCbl), in 8 min were developed.
View Article and Find Full Text PDFTransl Anim Sci
December 2024
Department of Animal Sciences, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA.
We conducted two experiments to evaluate the effect of direct-fed microbials () on fermentation parameters and nutrient degradability with two different approaches using rumen fluid from lactating Holstein dairy cows. In Exp. 1, three doses of a DFM containing and () at doses of 3.
View Article and Find Full Text PDFJ Agric Food Chem
December 2024
INRAE, Biopolymères Intéractions Assemblages (BIA), 44000 Nantes, France.
The prevalence of food allergies has increased in recent decades in industrialized developed countries. Defects are influenced by environmental factors in early life, including early colonizers of the human gut microbiota. Therapeutic solutions are limited, and the lack of efficient treatments has led to the search for new treatments, including biotherapies.
View Article and Find Full Text PDFMicrob Genom
November 2024
Section for Food Microbiology, Gut Health and Fermentation, Department of Food Science, University of Copenhagen, Rolighedsvej 26, 1958 Frederiksberg C, Denmark.
The reconstruction of complete bacterial genomes is essential for microbial research, offering insights into genetic content, ontology and regulation. While Pacific Biosciences (PacBio) provides high-quality genomes, its cost remains a limitation. Oxford Nanopore Technologies (ONT) offers long reads at a lower cost, yet its error rate raises scepticism.
View Article and Find Full Text PDFSci Rep
October 2024
Department of Integrated Biomedical and Life Sciences, Graduate School, Korea University, Seoul, 02841, Republic of Korea.
Rheumatoid arthritis causes excessive bone loss by stimulating osteoclast differentiation. Extracellular vesicles are valuable disease markers, conveyors of distant cell-to-cell communication, and carriers for drug delivery. The aim of this study was to investigate the anti-osteoclastogenic effects of extracellular vesicles derived from dairy Propionibacterium freudenreichii MJ2 (PFEVs) and the improvement effect of PFEVs on collagen-induced arthritis (CIA) animal model.
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