BackgroundObesity and type 2 diabetes (T2D) are linked both with host genetics and with environmental factors, including dysbioses of the gut microbiota. However, it is unclear whether these microbial changes precede disease onset. Twin cohorts present a unique genetically-controlled opportunity to study the relationships between lifestyle factors and the microbiome. In particular, we hypothesized that family-independent changes in microbial composition and metabolic function during the sub-clinical state of T2D could be either causal or early biomarkers of progression.MethodsWe collected fecal samples and clinical metadata from 20 monozygotic Korean twins at up to two time points, resulting in 36 stool shotgun metagenomes. While the participants were neither obese nor diabetic, they spanned the entire range of healthy to near-clinical values and thus enabled the study of microbial associations during sub-clinical disease while accounting for genetic background.ResultsWe found changes both in composition and in function of the sub-clinical gut microbiome, including a decrease in Akkermansia muciniphila suggesting a role prior to the onset of disease, and functional changes reflecting a response to oxidative stress comparable to that previously observed in chronic T2D and inflammatory bowel diseases. Finally, our unique study design allowed us to examine the strain similarity between twins, and we found that twins demonstrate strain-level differences in composition despite species-level similarities.ConclusionsThese changes in the microbiome might be used for the early diagnosis of an inflamed gut and T2D prior to clinical onset of the disease and will help to advance toward microbial interventions.Electronic supplementary materialThe online version of this article (doi:10.1186/s13073-016-0271-6) contains supplementary material, which is available to authorized users.

This article identifies novel factors involved in cholesterol reduction by probiotic bacteria, which were identified using genetic and proteomic approaches. Approximately 600 Lactobacillus acidophilus A4 mutants were created by random mutagenesis. The cholesterol-reducing ability of each mutant was determined and verified using two different methods: the o-phthalaldehyde assay and gas chromatographic analysis (GC). Among screened mutants, strain BA9 showed a dramatically diminished ability to reduce cholesterol, as demonstrated by a 7.7% reduction rate, while the parent strain had a more than 50% reduction rate. The transposon insertion site was mapped using inverse PCR (I-PCR), and it was determined using bioinformatic methods that the deleted region contained the Streptococcus thermophilus catabolite control protein A gene (ccpA). In addition, we have shown using two-dimensional gel electrophoresis (2-DE) that several proteins, including a transcription regulator, FMN-binding protein, major facilitator superfamily permease, glycogen phosphorylase, the YknV protein, and fructose/tagatose bisphosphate aldolase, were strongly regulated by the ccpA gene. In addition, in vivo experiments investigating ccpA function were conducted with rats. Rats fed wild-type L. acidophilus A4 showed a greater than 20% reduction in total serum cholesterol, but rats fed BA9 mutant L. acidophilus showed only an approximately 10% reduction in cholesterol. These results provide important insights into the mechanism by which these lactic acid bacteria reduce cholesterol.

bMillions of people suffer from foodborne diseases throughout the world every year, and the importance of food safety has grown worldwide in recent years. The aim of this study was to investigate the survival of hepatitis A virus (HAV) and viral surrogates of human norovirus (HuNoV) (bacteriophage MS2 and murine norovirus [MNV]) in food over time. HAV, MNV, and MS2 were inoculated onto either the digestive gland of oysters or the surface of fresh peppers, and their survival on these food matrices was measured under various temperature (4°C, 15°C, 25°C, and 40°C) and relative humidity (RH) (50% and 70%) conditions. Inoculated viruses were recovered from food samples and quantified by a plaque assay at predetermined time points over 2 weeks (0, 1, 3, 7, 10, and 14 days). Virus survival was influenced primarily by temperature. On peppers at 40°C and at 50% RH, >4-and 6-log reductions of MNV and HAV, respectively, occurred within 1 day. All three viruses survived better on oysters. In addition, HAV survived better at 70% RH than at 50% RH. The survival data for HAV, MS2, and MNV were fit to three different mathematical models (linear, Weibull, and biphasic models). Among them, the biphasic model was optimum in terms of goodness of fit. The results of this study suggest that major foodborne viruses such as HAV and HuNoV can survive over prolonged periods of time with a limited reduction in numbers. Because a persistence of foodborne virus on contaminated foods was observed, precautionary preventive measures should be performed.T hroughout the world, millions of people suffer from foodborne diseases every year, and the number of patients is predicted to increase in proportion to global warming (1-3). Foodborne diseases are transmitted via fecal-oral routes and person-to-person contact. Among the numerous enteric pathogenic viruses, human norovirus (HuNoV) and hepatitis A virus (HAV) are considered to be the most important. In recent reports (4-6), foodborne outbreaks of HuNoV and HAV were closely associated with fresh produce (e.g., leafy greens and fruits, etc.), shellfish (oysters and clams, etc.), and readyto-eat foods (e.g., salads and sandwiches, etc.).HuNoV is considered to be the leading cause of foodborne outbreaks worldwide (7). However, despite its importance to public health, the inability to cultivate HuNoV in vitro makes research difficult (8, 9). Therefore, several viruses, including feline calicivirus (FCV), murine norovirus (MNV), Tulane virus, and bacteriophage MS2, have been proposed as surrogates for HuNoV (10-13) due to similarities in size and genome structure. The incidence rate of hepatitis A has decreased in most developed countries, but massive sporadic outbreaks of hepatitis A from contaminated foods have been continuously reported worldwide (14-16). For example, Ͼ2 million patients were infected through the consumption of HAV-contaminated oysters in China (17).Viruses cannot replicate in food or water because an appropriate host is required for viral replication. After contamination occurs, ...

Fermented soybean products with Bacillus spp. are indigenous to Asian and African countries, which have long traditional ties to this nutritious food source. The fermentation products derived from these foods are also known to act as anticarcinogenic agents and antioxidants [8]. Out of these health-promoting strains, Bacillus spp. strains, including B. subtilis and B. licheniformis, are known to play a major role in the soybean fermentation process [10]. In other words, the quality and functionality of fermented soybean products such as doenjang, cheongkookjang, kochujang, and kanjang are affected by microbes, the fermentation process, and input materials such as soybeans or grains [15]. Previous studies showed that after co-inoculation of B. licheniformis SCK 121057 and B. cereus at a ratio of 10 to 1 on the surface of cooked soybeans, the cell count of B. cereus had been dramatically reduced after 31 days of

Inhibitory effects of the κ-casein macropeptide isolated from milk protein on the biofilm formation and virulence of Listeriamonocytogenes, Bioscience, Biotechnology, and Biochemistry, 78:3,[490][491][492][493][494][495][496][497][498]