Lantibiotics Produced by Oral Inhabitants as a Trigger for Dysbiosis of Human Intestinal Microbiota

Abstract

Lantibiotics are a type of bacteriocin produced by Gram-positive bacteria and have a wide spectrum of Gram-positive antimicrobial activity. In this study, we determined that Mutacin I/III and Smb (a dipeptide lantibiotic), which are mainly produced by the widespread cariogenic bacterium Streptococcus mutans, have strong antimicrobial activities against many of the Gram-positive bacteria which constitute the intestinal microbiota. These lantibiotics also demonstrate resistance to acid and temperature. Based on these features, we predicted that lantibiotics may be able to persist into the intestinal tract maintaining a strong antimicrobial activity, affecting the intestinal microbiota. Saliva and fecal samples from 69 subjects were collected to test this hypothesis and the presence of lantibiotics and the composition of the intestinal microbiota were examined. We demonstrate that subjects possessing lantibiotic-producing bacteria in their oral cavity exhibited a tendency of decreased species richness and have significantly reduced abundance of the phylum Firmicutes in their intestinal microbiota. Similar results were obtained in the fecal microbiota of mice fed with S. mutans culture supernatant containing the lantibiotic bacteriocin Mutacin I. These results showed that lantibiotic bacteriocins produced in the oral cavity perturb the intestinal microbiota and suggest that oral bacteria may be one of the causative factors of intestinal microbiota dysbiosis.

Deep metagenomic characterization of gut microbial community and function in preeclampsia

“…The bacteriocins production capability of Blautia leads to the reduced intestinal colonization of some pathogenic bacteria (Liu et al, 2021). Yonezawa et al demonstrated that lantibiotic bacteriocins produced in oral bacteria may be one of the causative factors of intestinal microbiota dysbiosis (Yonezawa et al, 2021). In addition, PEenriched bacteria, such as Desulfovibrio (Korenblum et al, 2005), Bacteroides (Guinane et al, 2016), and Eubacterium (Le Blay et al, 2007), could be inhibited by the bacitracin/lantibiotics produced by gut microbiota.…”

Optimizing ex vivo culture conditions to study human gut microbiome

“…Evaluating the impacts of culture time on outcomes of human fecal bacteria culture Culturing time and medium are two critical factors in affecting the outcomes of bacteria culture. To determine the optimal incubation time, freshly collected feces from one health donor were cultured in five different media that were frequently used for culture of mixed bacteria [15,26,27] and sampled at 6, 12, 24, and 48 h (Fig. 1A).…”

“…In agreement with the main impactor of interindividual difference on gut microbiome [15,35], we proved that the type of culture medium was the key factor for introducing variations to the outcome of bacteria culture, and followed by culture time. Unfortunately, the impacts of culture medium on gut microbiome were largely overlooked because different kinds of culture medium for mixed bacteria culture were used in most studies such mGAM, GAM, GMM, BHI with little attention to the variations that may be introduced by culture medium, as well as the culture time [12,15,26,27,[35][36][37].…”

Regulatory effects of oral microbe on intestinal microbiota and the illness

“…During periodontitis, the liver is constantly exposed to pathogenic factors from the oral, periodontitis-related systemic hypo-inflammation and chemokine potentially affect hepatic metabolic pathways. Both fecal and salivary microbiota have independent prognostic value for cirrhosis progress, specifically, via impaired salivary defense ( Yonezawa et al., 2021 ; Jia et al., 2022 ; Saboo et al., 2022 ). The subgingival microbiota of cirrhotic patients consists of an uncommon bacterial community, indicating that its origin is from ecological dysregulation by immune system impairment ( Jensen et al., 2018 ).…”

“…In terms of gastrointestinal motility disorders, a polybacterial infection ( P. gingivalis , T. denticola , and Tannerella forsythia ) is discovered to alter vascular and colonic BH4/nNOS/NRF2 pathways and to damage vascular relaxation and colonic motility ( Gangula et al., 2015 ). In addition, oral lantibiotics (it has a considerable antimicrobial effect on intestinal gram-positive bacteria) produced by S. mutans decrease the diversity of intestinal microbes and reduce the abundance of Firmicutes ( Yonezawa et al., 2021 ).…”