Phascolarctobacterium can produce short-chain fatty acids, including acetate and propionate, and can be associated with the metabolic state and mood of the host. The present study investigated the colonization characteristics of Phascolarctobacterium faecium in healthy individuals <1-80 years old in Southern China. A total of 150 fresh fecal samples were collected, and bacterial DNA was isolated from these samples for quantitative polymerase chain reaction analysis. Phascolarctobacterium faecium demonstrated a high colonization rate and abundant colonization in the human gastrointestinal tract. The colonization rate varied between 43.33‑93.33%, and the abundance of Phascolarctobacterium faecium ranged between 3.22‑5.76 log cells g‑1 (1 year old). The permillage of Phascolarctobacterium faecium in total bacteria ranged between 0.004‑1.479. There was presence of Phascolarctobacterium faecium‑like bacteria in younger individuals with a gradual increase in the number of bacteria maintained at a high level with increasing ages (between 1 and 60 years old), but with a decrease in elderly individuals (>60 years old). The results of the present study demonstrated that Phascolarctobacterium faecium is abundantly colonized in the human gastrointestinal tract.

Objective: Alzheimer’s disease (AD) is a global health problem without effective methods to alleviate the disease progression. Amyloid β-protein (Aβ) is widely accepted as a key biomarker for AD. Metabolic syndromes, including obesity and insulin resistance, are key high risk factors for AD. Akkermansia muciniphila (Akk), the only representative human gut microbe in the genus Verrucomicrobia, can prevent the weight gain caused by a high-fat diet, repair the damaged integrity of the intestinal epithelium barrier, reduce endotoxin levels in blood and improve insulin resistance. The aim of this study is to explore the impact of Akk administration in AD model mice in different diets. Methods: APP/PS1 mice were fed either a normal chow diet or a high-fat diet and were treated with Akk by gavage each day for 6 months. The impacts of Akk on glucose metabolism, intestinal barrier and lipid metabolism in the mouse model of AD were determined. Changes in brain pathology and neuroethology were also analyzed. Results: Akk effectively reduced the fasting blood glucose and serum diamine oxidase levels, and alleviated the reduction of colonic mucus cells in APP/PS1 mice. After treatment with Akk, the APP/PS1 mice showed obviously reduced blood lipid levels, improved hepatic steatosis and scapular brown fat whitening. Moreover, Akk promoted the reduction of Aβ 40–42 levels in the cerebral cortex of APP/PS1 mice, shortened the study time and improved the completion rate in Y-maze tests. Conclusion: Akk effectively improved glucose tolerance, intestine barrier dysfunction and dyslipidemia in AD model mice. Our study results suggested that Akk could delay the pathological changes in the brain and relieve impairment of spatial learning and memory in AD model mice, which provides a new strategy for prevention and treatment of AD.

Akkermansia muciniphila is one of the most dominant bacteria that resides on the mucus layer of intestinal tract and plays key role in human health, however, little is known about its genomic content. Herein, we for the first time characterized the genomic architecture of A. muciniphila based on whole-genome sequencing, assembling, and annotating of 39 isolates derived from human and mouse feces. We revealed a flexible open pangenome of A. muciniphila currently consisting of 5644 unique proteins. Phylogenetic analysis identified three species-level A. muciniphila phylogroups exhibiting distinct metabolic and functional features. Based on the comprehensive genome catalogue, we reconstructed 106 newly A. muciniphila metagenome assembled genomes (MAGs) from available metagenomic datasets of human, mouse and pig gut microbiomes, revealing a transcontinental distribution of A. muciniphila phylogroups across mammalian gut microbiotas. Accurate quantitative analysis of A. muciniphila phylogroups in human subjects further demonstrated its strong correlation with body mass index and anti-diabetic drug usage. Furthermore, we found that, during their mammalian gut evolution history, A. muciniphila acquired extra genes, especially antibiotic resistance genes, from symbiotic microbes via recent lateral gene transfer. The genome repertoire of A. muciniphila provided insights into population structure, evolutionary and functional specificity of this significant bacterium.

An important intestinal bacterial strain Akkermansia muciniphila contributes to improving carbohydrate and lipid metabolism, thus alleviating obesity symptoms. Here, we find that the Akk membrane protein Amuc_1100 regulates lipid metabolism in 3T3-L1 preadipocytes.

This study investigates the colonization rate of Akkermansia muciniphila in the gastrointestinal tracts of people living in southern China and applies a modified method for the isolation and sub-typing of A.muciniphila strains from fecal samples. Fresh fecal samples were collected and bacterial DNA was extracted from these samples for real-time PCR analysis. Strains were separated using a culture-dependent sPCR-directed method and classified using an enterobacterial repetitive intergenic consensus (ERIC-PCR) DNA fingerprinting method. The colonization rate for the sample population from southern China was 51.74%. We isolated 22 strains from human feces. The results revealed that all strains were identifiable as A. muciniphila with 99% to 100% identity to the type-strain ATCC BAA-835. ERIC-PCR resulted in grouping of the DNA fingerprints showed that 12 distinct clusters were distinguished with a delineation level of 100%. Southern China has a high rate of A.muciniphila colonization and over 12 different sub-type strains reside in fecal samples. A.muciniphila has a beneficial role in human gastrointestinal tract. These studies provide a better understanding of A.muciniphila and details of its colonization in the human gastrointestinal tract.