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Frontiers in Microbiology 2022Smoked horsemeat sausage is a famous fermented traditional food in Xinjiang, China. However, the microbial diversity and its potential contributions to the flavor...
Smoked horsemeat sausage is a famous fermented traditional food in Xinjiang, China. However, the microbial diversity and its potential contributions to the flavor components of smoked horsemeat sausage are unclear. In this study, the microbial community and flavor components of smoked horsemeat sausage from six regions of Xinjiang were measured by using amplicon sequencing and headspace solid-phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS) technology, respectively. Relations among microbial communities, flavor components and environmental factors were subsequently predicted based on redundancy analysis (RDA) and Monte Carlo permutation tests. Although smoked horsemeat sausage samples from different regions possessed distinct microbial communities, lactic acid bacteria (LAB) were identified as the dominant consortium in smoked horsemeat sausage. , , , and were detected at high abundance in different sausages. The moisture content, nitrite content, and pH of the sausage might be important factors influencing the dominant bacterial community, according to the RDA. Among the dominant consortia, the eight core bacterial genera showed considerable correlations with the formation of sixteen volatile compounds in smoked horsemeat sausage based on multivariate statistical analysis. For example, the levels of and were positively correlated with those of 1-hexadecanol, hexyl acetate, 2-methyl-phenol, 1-pentanol, d-limonene, and 2-heptanone, and the levels of , , and were negatively correlated with those of 1-octanol, acetic acid, octanal, heptanal, and 1-hexanol. This study will provide a theoretical basis for understanding the microbial metabolic modes of Xinjiang smoked horsemeat sausages.
PubMed: 35966695
DOI: 10.3389/fmicb.2022.942932 -
Frontiers in Nutrition 2022Angiotensin I converting enzyme (ACE) inhibitory peptides from fermented foods exhibit great potential to alleviate hypertension. In this study, the peptide extract from...
Angiotensin I converting enzyme (ACE) inhibitory peptides from fermented foods exhibit great potential to alleviate hypertension. In this study, the peptide extract from exhibited a good inhibition effect on ACE, and the inhibition rate was significantly enhanced after fermentation for 8 days. The ACE inhibitory peptides were further identified, followed by their inhibition and formation mechanisms using microbiome technology and molecular docking. A total of 356 ACE inhibitory peptides were predicted using , and most ACE inhibitory peptides increased after fermentation. These peptides could be hydrolyzed from 94 kinds of precursor proteins, mainly including muscle-type creatine kinase, nebulin, and troponin I. P1 (VEIINARA), P2 (FAVMVKG), P4 (EITWSDDKK), P7 (DFDDIQK), P8 (IGDDPKF), P9 (INDDPKIL), and P10 (GVDNPGHPFI) were selected as the core ACE inhibitory peptides according to their abundance and docking energy. The salt bridge and conventional hydrogen bond connecting unsaturated oxygen atoms in the peptides contributed most to the ACE inhibition. The cleavage proteases from the microbial genera in for preparing these 7 core ACE inhibitory peptides were further analyzed by hydrolysis prediction and Pearson's correlation. The correlation network showed that P7, P8, and P9 were mainly produced by the proteases from LAB including , and , while P1, P2, P4, and P10 were mainly Produced by , and . This study is helpful in isolating the proteases and microbial strains to directionally produce the responding ACE inhibitory peptides.
PubMed: 35938113
DOI: 10.3389/fnut.2022.920945 -
Microbiology Spectrum Aug 2022Infections caused by multiresistant pathogens have become a major problem in both human and veterinary medicine. Due to the declining efficacy of many antibiotics, new...
Infections caused by multiresistant pathogens have become a major problem in both human and veterinary medicine. Due to the declining efficacy of many antibiotics, new antimicrobials are needed. Promising alternatives or additions to antibiotics are bacteriocins, antimicrobial peptides of bacterial origin with activity against many pathogens, including antibiotic-resistant strains. From a sample of fermented maize, we isolated a Vagococcus fluvialis strain producing a bacteriocin with antimicrobial activity against multiresistant Enterococcus faecium. Whole-genome sequencing revealed the genes for a novel two-peptide lantibiotic. The production of the lantibiotic by the isolate was confirmed by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry, which revealed distinct peaks at 4,009.4 and 3,181.7 in separate fractions from reversed-phase chromatography. The combination of the two peptides resulted in a 1,200-fold increase in potency, confirming the two-peptide nature of the bacteriocin, named vagococcin T. The bacteriocin was demonstrated to kill sensitive cells by the formation of pores in the cell membrane, and its inhibition spectrum covers most Gram-positive bacteria, including multiresistant pathogens. To our knowledge, this is the first bacteriocin characterized from . Enterococci are common commensals in the intestines of humans and animals, but in recent years, they have been identified as one of the major causes of hospital-acquired infections due to their ability to quickly acquire virulence and antibiotic resistance determinants. Many hospital isolates are multiresistant, thereby making current therapeutic options critically limited. Novel antimicrobials or alternative therapeutic approaches are needed to overcome this global problem. Bacteriocins, natural ribosomally synthesized peptides produced by bacteria to eliminate other bacterial species living in a competitive environment, provide such an alternative. In this work, we purified and characterized a novel two-peptide lantibiotic produced by Vagococcus fluvialis LMGT 4216 isolated from fermented maize. The novel lantibiotic showed a broad spectrum of inhibition of Gram-positive strains, including vancomycin-resistant Enterococcus faecium, demonstrating its therapeutic potential.
Topics: Anti-Bacterial Agents; Bacteriocins; Enterococcaceae; Peptides; Vancomycin-Resistant Enterococci
PubMed: 35730941
DOI: 10.1128/spectrum.00954-22 -
Frontiers in Microbiology 2022Insects have a long history of being used in medicine, with clear primary and secondary functions and less side effects, and the study and exploitation of medicinal...
Insects have a long history of being used in medicine, with clear primary and secondary functions and less side effects, and the study and exploitation of medicinal insects have received increasing attention. Insects gut microbiota and their metabolites play an important role in protecting the hosts from other potentially harmful microbes, providing nutrients, promoting digestion and degradation, and regulating growth and metabolism of the hosts. However, there are still few studies linking the medicinal values of insects with their gut microbes. In this study, we focused on the specific gut microbiota common to medicinal insects, hoping to trace the potential connection between medicinal values and gut microbes of medicinal insects. Based on 16S rRNA gene sequencing data, we compared the gut microbiota of medicinal insects [, () (Lewis) and ], in their medicinal stages, and non-medicinal insects ( L., , and ), and found that the intestinal microbial richness of medicinal insects was higher, and there were significant differences in the microbial community structure between the two groups. We established a model using a random-forest method to preliminarily screen out several types of gut microbiota common to medicinal insects that may play medicinal values: , , subsp. (), and . In particular, and were most probably involved in the anti-inflammatory effects of medicinal insects. Our results revealed an association between medicinal insects and their gut microbes, providing new development directions and possibly potential tools for utilizing microbes to enhance the medicinal efficacy of medicinal insects.
PubMed: 35651499
DOI: 10.3389/fmicb.2022.892767 -
Revista Espanola de Enfermedades... Nov 2022Ascites is the most common complication of the decompansated cirrhosis. The most common organisms isolated in patients with ascidic fluid infections and spontaneous...
Ascites is the most common complication of the decompansated cirrhosis. The most common organisms isolated in patients with ascidic fluid infections and spontaneous bacterial peritonitis (SBP) are intestinal pathogens including Escherichia coli, Gram-positive cocci (mainly Streptococcus species) and Enterococci. As an infectious pathogen Vagococcus spp. can be isolated from animals such as pigs, cats, horses and fishes and also rarely in humans. In this paper, we present a case of Vagococcus fluvialis peritonitis which is the first one reported in a cirrhotic patient with ascites.
Topics: Humans; Animals; Swine; Horses; Ascitic Fluid; Ascites; Gram-Positive Cocci; Peritonitis; Liver Cirrhosis; Enterococcaceae; Bacterial Infections
PubMed: 35485244
DOI: 10.17235/reed.2022.8852/2022 -
PeerJ 2022Although studies have shown that Bacteroidetes, Clostridiales, and Lactobacillales are the main components of the microbial community in pit mud during the brewing of...
BACKGROUND
Although studies have shown that Bacteroidetes, Clostridiales, and Lactobacillales are the main components of the microbial community in pit mud during the brewing of Luzhou-flavored liquor, little is known about the effect of brewing materials on spatial structures of this microbiome.
METHODS
High-throughput sequencing of the V4-V5 region of prokaryotic 16S rRNA gene was performed to analyze the microbial community diversity and spatial heterogeneity in Luzhou-flavored liquor pit muds with different brewing ingredients. The structural characteristics and heterogeneous spatial distribution of the pit mud microbial communities were examined using bioinformatics and multivariate statistical analysis methods.
RESULTS
Our results showed that Euryarchaeota, Actinobacteria, Bacteroidetes, Chlorobi, Chloroflexi, Firmicutes, Proteobacteria, Synergistetes, Tenericutes, and WWE1 were the dominant phyla in the pit mud microbiome. The Shannon and Simpson indices of the pit mud microbiome with three grains (M3G) in the upper layer were significantly lower than those in middle layer and bottom, whereas those of the pit mud microbiome with five grains (M5G) in bottom were significantly lower than those in middle layer ( < 0.05). There were significant differences in the microbial community compositions between the pit muds with different brewing ingredients and locations in the same pit ( < 0.05). T78 of Anaerolinaceae, , , , , and vadinCA02 of Synergistaceae were significantly enriched in M3G, whereas , , , , , , , , , RFN20 of Erysipelotrichaceae, , 125ds10 of Alteromonadales, , and were significantly enriched in M5G. This study provides a theoretical basis for exploring the influence of brewing ingredients in pit muds on the production of Luzhou-flavored liquor and the specific influence of pit mud microorganisms in different locations on liquor production.
Topics: RNA, Ribosomal, 16S; Fermentation; Bacteria; Alcoholic Beverages; Microbiota; Firmicutes; Bacteroidetes
PubMed: 35282287
DOI: 10.7717/peerj.12987 -
Microorganisms Jan 2022Chile has promoted the diversification of aquaculture and red cusk-eel () is one of the prioritized species. However, many aspects of the biology of the species are...
Chile has promoted the diversification of aquaculture and red cusk-eel () is one of the prioritized species. However, many aspects of the biology of the species are unknown or have little information available. These include intestinal microbiota, an element that may play an important role in the nutrition and defense of cultured animals for meat production. This study compares the microbiota composition of the intestinal contents of wild and aquaculture fish to explore the microbial communities present and their potential contribution to the host. DNA was extracted from the intestinal content samples and the V4 region of the 16S rRNA gene was amplified and sequenced using the Ion Torrent platform. After the examination of the sequences, strong differences were found in the composition at the level of phylum, being and the most abundant in aquaculture and wild condition, respectively. At the genus level, the (54%) and (97%) were the most prevalent in the microbial community of aquaculture and wild condition, respectively. The evaluation of predicted metabolic pathways in these metagenomes showed that in wild condition there is an important presence of lipid metabolism belonging to the unsaturated fatty acid synthesis. In the aquaculture condition, the metabolism of terpenoids and polyketides were relevant. To our knowledge, this is the first study to characterize and compare the intestinal microbiota of red cusk-eel () of wild and aquaculture origin using high-throughput sequencing.
PubMed: 35056554
DOI: 10.3390/microorganisms10010105 -
Animals : An Open Access Journal From... Dec 2021In times of massive biodiversity loss and ongoing environmental crises, it is extremely important to ensure long-term conservation efforts of threatened species like...
In times of massive biodiversity loss and ongoing environmental crises, it is extremely important to ensure long-term conservation efforts of threatened species like Eurasian otters (). To gain insights into the status of Northern Germany's otter population, 92 otters found dead in Schleswig-Holstein between 2015-2020 were collected and underwent detailed dissection with the aim to establish a monitoring program for this population. Examinations followed a protocol especially designed for otters, including various biological data assessments and extended sampling. The finding sites showed a clear concentration in the Continental region. Seasonal concentration differed among the years, yet peaks were seen from fall to winter. Overall, more males than females were found, although this differed among the years. The majority of otters that could be aged were between 1-3 years. Placental scars and pregnancy were recorded in only few females. Nutritional status was good in most cases. Infectious diseases found included , , and spp. A major cause of death was roadkill. Known sample bias in studies focusing on roadkill was considered in the finding interpretation. Continuation of the population health investigations is mandatory to analyze potential trends and to establish an actual monitoring program for Eurasian otters in Schleswig-Holstein.
PubMed: 35011165
DOI: 10.3390/ani12010059 -
Folia Microbiologica Apr 2022This work aimed to identify the key members of the bacterial community growing on common carp (Cyprinus carpio) fillets during chilled storage with next-generation...
This work aimed to identify the key members of the bacterial community growing on common carp (Cyprinus carpio) fillets during chilled storage with next-generation sequencing (NGS) and cultivation-dependent methods. Carp fillets were stored for 96 h at 2 °C and 6 °C with and without a vacuum package, and an additional frozen-thawed storage experiment was set for 120 days. Community profiles of the initial and stored fish samples were determined by amplicon sequencing. Conventional microbial methods were used parallelly for the enumeration and cultivation of the dominant members of the microbial community. Cultivated bacteria were identified with 16S rRNA sequencing and the MALDI-TOF MS method. Based on our results, the vacuum package greatly affected the diversity and composition of the forming microbial community, while temperature influenced the cell counts and consequently the microbiological criteria for shelf-life of the examined raw fish product. Next-generation sequencing revealed novel members of the chilled flesh microbiota such as Vagococcus vulneris or Rouxiella chamberiensis in the vacuum-packed samples. With traditional cultivation, 161 bacterial strains were isolated and identified at the species level, but the identified bacteria overlapped with only 45% of the dominant operational taxonomic units (OTUs) revealed by NGS. Next-generation sequencing is a promising and highly reliable tool recommended to reach a higher resolution of the forming microbial community of stored fish products. Knowledge of the initial microbial community of the flesh enables further optimization and development of processing and storage technology.
Topics: Animals; Bacteria; Carps; Food Microbiology; Food Storage; Microbiota; RNA, Ribosomal, 16S; Seafood
PubMed: 34877630
DOI: 10.1007/s12223-021-00935-4 -
Parasites & Vectors Dec 2021As a pervasive insect that transmits a variety of pathogens to humans and animals, the housefly has abundant and diverse microbial communities in its intestines. These...
BACKGROUND
As a pervasive insect that transmits a variety of pathogens to humans and animals, the housefly has abundant and diverse microbial communities in its intestines. These gut microbes play an important role in the biology of insects and form a symbiotic relationship with the host insect. Alterations in the structure of the gut microbial community would affect larval development. Therefore, it is important to understand the mechanism regulating the influence of specific bacteria on the development of housefly larvae.
METHODS
For this study we selected the intestinal symbiotic bacterium Enterobacter hormaechei, which is beneficial to the growth and development of housefly larvae, and used it as a probiotic supplement in larval feed. 16S rRNA gene sequencing technology was used to explore the effect of E. hormaechei on the intestinal flora of housefly larvae, and plate confrontation experiments were performed to study the interaction between E. hormaechei and intestinal microorganisms.
RESULTS
The composition of the gut microflora of the larvae changed after the larvae were fed E. hormaechei, with the abundance of Pseudochrobactrum, Enterobacter and Vagococcus increasing and that of Klebsiella and Bacillus decreasing. Analysis of the structure and interaction of larval intestinal flora revealed that E. hormaechei inhibited the growth of harmful bacteria, such as Pseudomonas aeruginosa, Providencia stuartii and Providencia vermicola, and promoted the reproduction of beneficial bacteria.
CONCLUSIONS
Our study has explored the influence of specific beneficial bacteria on the intestinal flora of houseflies. The results of this study reveal the important role played by specific beneficial bacteria on the development of housefly larvae and provide insight for the development of sustained biological agents for housefly control through interference of gut microbiota.
Topics: Animals; Enterobacter; Female; Gastrointestinal Microbiome; Houseflies; Humans; Intestines; Larva; Male; Probiotics; Symbiosis
PubMed: 34876203
DOI: 10.1186/s13071-021-05053-1