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Lactic Acid Bacteria Application to Decrease Food Allergies
Published in Marcela Albuquerque Cavalcanti de Albuquerque, Alejandra de Moreno de LeBlanc, Jean Guy LeBlanc, Raquel Bedani, Lactic Acid Bacteria, 2020
Vanessa Biscola, Marcela Albuquerque Cavalcanti de Albuquerque, Tatiana Pacheco Nunes, Antonio Diogo Silva Vieira, Bernadette Dora Gombossy de Melo Franco
The proteolytic activity of LAB enzymes against milk allergens is dependent on the strain used and on the process conditions. Different strains have been reported to produce enzymes capable of hydrolyzing milk antigens. Although Enterococcus spp. is frequently reported as one of the most proteolytic LAB found in dairy products, possessing a very efficient proteolytic system and a strong activity against both caseins and β-lactoglobulin, its application in foods for technological purposes is a controversial issue, since Enterococcus spp. are related to nosocomial infections and reported to harbor several virulence factors (Kim et al. 2016). LAB species belonging to other genera, such as Lactobacillus spp., Lactococcus spp. and Streptococcus spp. have also been reported to produce proteolytic enzymes with activity against milk allergens. The interest in their application in foods relies on their relevant role as fermentation starters and/or on their association with beneficial health effects, some being recognized as probiotics.
Bacteriophage Involvement in Neurodegenerative Diseases
Published in David Perlmutter, The Microbiome and the Brain, 2019
As stated above, phages can cause bacterial population lysis, leading to the development of diseases associated with microbiota phenotype, which is in turn implicated as a triggering or worsening factor for certain pathologies.31,62 Our previous studies implicated this mechanism of phage-induced microbiota in Parkinson’s, which may share common features with Alzheimer’s.32,62 By studying the microbiota of Parkinson’s patients, we found a significantly decreased abundance of neurotransmitter-producing Lactococcus bacteria due to lytic Lactococcus phages. This association was particularly notable as Lactococcus spp. are known to produce intestinal dopamine, the decrease of which is linked to the development of increased intestinal permeability and development of Parkinson’s gastrointestinal symptoms and α-synuclein misfolding.32,63,64
Beneficial Lactic Acid Bacteria
Published in K. Balamurugan, U. Prithika, Pocket Guide to Bacterial Infections, 2019
Random amplified polymorphism DNA (RAPD) is the method in which arbitrary primers (typically 10-mer primers) are used to randomly amplify segments of target DNA under low-stringency PCR conditions with generation of the set of finger printing patterns of different sizes specific to each strain (Adzitey et al. 2013). The technique was successfully tested in identification of Lactobacillus, Lactococcus, Enterococcus, and Streptococcus strains (Cocconcelli et al. 1995; Samarzija et al. 2002; Rossetti and Giraffa 2005). Additionally, RAPD can follow and study the progression of starter cultures in food fermentations (Plengvidhya et al. 2004; Siragusa et al. 2009).
An oxidation resistant pediocin PA-1 derivative and penocin A display effective anti-Listeria activity in a model human gut environment
Published in Gut Microbes, 2022
Taís M. Kuniyoshi, Paula M. O’Connor, Elaine Lawton, Dinesh Thapa, Beatriz Mesa-Pereira, Sara Abulu, Colin Hill, R. Paul Ross, Ricardo P. S. Oliveira, Paul D. Cotter
Chemical synthesis of penocin A, another bacteriocin that harbors a YGNGVX1CX2K/NX3X4C, (X1–4:polar uncharged or charged residues) pediocin box in its sequence was carried out in tandem to compare its antimicrobial efficacy against L. monocytogenes and the commensal gut microbiota. Penocin A is considered a silent bacteriocin as its mature form is not produced naturally due to the absence of a key gene(s) in the associated natural strains. Diep et al.23 revealed that heterologous expression of the pediocin inducer factor led to penocin A expression in Pediococcus pentosaceus 25745 and its inhibition rate against 71 strains from a collection of 8 Gram positive bacteria genera (Carnobacterium, Clostridioides, Enterococci, Lactobacilli, Lactococci, Leuconostoc, Listeriae, Pediococci) was lower (48%) than that presented by pediocin PA-1 (58%). This reduced antimicrobial activity against some important bacterial groups (e.g Lactobacilli, Lactococci, Leuconostoc) may be a desirable feature when used as a therapeutic agent. Here the anti-Listeria effects of pure forms of recombinant pediocin M31L, natural pediocin PA-1 and synthetic penocin A were each evaluated in an ex vivo model that simulates the human gut environment for the first time. This study verifies the efficiency of the pediocin variants against L. monocytogenes and highlights the merits of progressing to in vivo experiments.
Low Abundance of Lactococcus lactis in Human Colorectal Cancer Is Associated with Decreased Natural Killer Cells
Published in Nutrition and Cancer, 2022
Huan Li, Xinhao Du, Li Yan, Zhenzhen Tang, Ling Zhang, Qiao Zheng, Xianghao Zeng, Guimei Chen, Huawen Yue, Xiangsheng Fu
Lactococcus lactis (L. lactis) is a Gram-positive probiotic, which belongs to the genus Lactococcus (14, 15). The cytoplasmic fraction of L. lactis can change the expression levels of cell-cycle regulatory proteins in CRC cells, which include cyclin A, p21Cip1, cyclin E, and cyclin-dependent kinase 2 (CDK2) (12). The treatment of lipopolysaccharide (LPS)-stimulated macrophages with L. lactis decreases the secretion of tumor necrosis factor-α (TNF-α), nitric oxide (NO), interleukin-18 (IL-18), and cyclooxygenase-2 (COX-2) (10). In addition, the L. lactis has also been proven to increase the level of anti-inflammatory cytokine in animal models of CRC or colitis model (16, 17). Overall, it is evident that the L. lactis has potential anti-pathogenic and anticancer activity, which is due to the decrease in the pro-inflammatory cytokines and the inhibition of the proliferation of colorectal tumor cells (10, 12). However, the number of studies, which have explored the abundance of L. lactis in human CRCs, is limited.
B. adolescentis ameliorates chronic colitis by regulating Treg/Th2 response and gut microbiota remodeling
Published in Gut Microbes, 2021
Lina Fan, Yadong Qi, Siwen Qu, Xueqin Chen, Aiqing Li, Maher Hendi, Chaochao Xu, Lan Wang, Tongyao Hou, Jianmin Si, Shujie Chen
In this study, we demonstrated that the B. adolescentis ATCC15703 strain regulates the immune response and improves the symptoms of IBD via the gut microbiota. Genus Lactobacillus, Bifidobacterium and Lactococcus have been developed as probiotics and contribute to modulating intestinal inflammation. Many databases outline human gut metagenomic data covering many disease phenotypes. Among them, we searched a new database called GMrepo. The GMrepo is a curated and annotated human gut metagenomic data repository for microbiota. In the GMrepo database, we found B. adolescentis decreased in the IBD patients compared with the normal people (Figure 1). Accumulating evidence has indicated this bacterium has antiviral properties25 and ameliorates metabolic system inflammation and is considered a promising probiotic.26 However, few studies have focused on its microbial alteration and immune modulation, and whether B. adolescentis also has a favorable role in DSS related chronic colitis. Consistent with our assumption, we found oral of B. adolescentis relieved the symptoms of chronic colitis (Figure 2).