Rapid in vivo Colonization Screening of Probiotic Bacteria Isolated from Human Infants using Caenorhabditis elegans Surrogate Host

Abstract

The ability of probiotics to adhere to the intestinal epithelium likely plays an important role in their colonization of the gastrointestinal tract. Here, we performed high-throughput screening (HTS) for suitable characteristics of potential probiotic bacteria using attachment and colonization ability through a C. elegans surrogate in vivo model. A total of 100 strains of lactic acid bacteria (LAB) isolated from infant feces were subjected to the colonization assay using C. elegans intestine. Based on colonization ability, we showed that nine isolates have a high attachment ability during whole experimental periods (up to 168 h), compared to Lactobacillus rhamnosus strain GG as a control. Also, through the use of an in vitro cell attachment model, nine isolates revealed highly binding activity to the mucus layer. Next, the selected 9 isolates were assayed for their survival ability when exposed to acidic and bile conditions as well as cholesterol reduction and the utilization of prebiotic substrates. As a result, the isolated nine strains were determined to be highly resistant to acid and bile conditions. In addition, they have significant activity for the reduction of cholesterol and utilization of several prebiotic substrates as a carbon source. Finally, the selected nine strains were identified by either L. rhamnosus or L. plantarum (4 strains for L. rhamnosus and 5 strains for L. plantarum, respectively). Taken together, we propose that the direct colonization of probiotics using C. elegans may be applicable to the rapid screening of valuable probiotic strains in vivo.

In vitroevaluation of the mucin-adhesion ability and probiotic potential ofLactobacillus mucosaeLM1

“…Thus, the ability to adhere to the host mucus layer and cells is an integral probiotic characteristic as it is a prerequisite for transient colonization (Beachey ; Ouwehand and Salminen ; Park et al . ), establishment of a functional microbial–host interaction to modulate the immune system (Erickson and Hubbard ; Delcenserie et al . ) and protection of the GIT (Tancrede ; Bernet et al .…”

“…However, to be able to confer health benefits, these probiotics must be able to survive the harsh environment of the host gastrointestinal tract (GIT) and thrive in the intestinal mucosa (Sahadeva et al 2011). Thus, the ability to adhere to the host mucus layer and cells is an integral probiotic characteristic as it is a prerequisite for transient colonization (Beachey 1981;Ouwehand and Salminen 2003;Park et al 2013), establishment of a functional microbial-host interaction to modulate the immune system (Erickson and Hubbard 2000;Delcenserie et al 2008) and protection of the GIT (Tancrede 1992;Bernet et al 1994;Collado et al 2007a). Adhesion studies of numerous probiotic bacteria have been performed; these have also emphasized their role in preventing colon cancer (Byrd and Bresalier 2004) and enhancing the overall microbial flora by inhibiting pathogens (Salminen et al 1996).…”

Short communication: In vivo screening platform for bacteriocins using Caenorhabditis elegans to control mastitis-causing pathogens

“…The C. elegans strain used in this study was glp-4(bn2);sek-1(km4) double mutant strain (Kim and Mylonakis, 2012). This nematode strain was routinely maintained on nematode growth medium plates seeded with Escherichia coli OP50, as described previously (Park et al, 2013).…”

Bacillus licheniformis Isolated from Traditional Korean Food Resources Enhances the Longevity of Caenorhabditis elegans through Serotonin Signaling

“…This animal does not present ethical issues, is inexpensive to maintain, and involves less time and labor for screening . Interestingly, the relationship between diet and longevity is an important consideration in the interpretation of assays of C. elegans life span involving modification of bacterial food source, and several studies have demonstrated that lactobacilli and bifidobacteria modify host defense and prolong the lifespan of nematodes. ,,, …”

“…10 Interestingly, the relationship between diet and longevity is an important consideration in the interpretation of assays of C. elegans life span involving modification of bacterial food source, and several studies have demonstrated that lactobacilli and bifidobacteria modify host defense and prolong the lifespan of nematodes. 7,8,11,12 It is well-established that the interactions between C. elegans and bacteria with respect to aging and host longevity are complicated and multifactorial, 13−15 among which the neurotransmitter serotonin has long been suggested to be an important food signal in C. elegans. 16 The unifying characteristic of C. elegans serotonergic responses is the coupling of food perception to various endocrine outputs.…”