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1.
Emerg Infect Dis ; 30(3): 460-468, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38407254

ABSTRACT

During January 28-May 5, 2019, a meningitis outbreak caused by Neisseria meningitidis serogroup C (NmC) occurred in Burkina Faso. Demographic and laboratory data for meningitis cases were collected through national case-based surveillance. Cerebrospinal fluid was collected and tested by culture and real-time PCR. Among 301 suspected cases reported in 6 districts, N. meningitidis was the primary pathogen detected; 103 cases were serogroup C and 13 were serogroup X. Whole-genome sequencing revealed that 18 cerebrospinal fluid specimens tested positive for NmC sequence type (ST) 10217 within clonal complex 10217, an ST responsible for large epidemics in Niger and Nigeria. Expansion of NmC ST10217 into Burkina Faso, continued NmC outbreaks in the meningitis belt of Africa since 2019, and ongoing circulation of N. meningitidis serogroup X in the region underscore the urgent need to use multivalent conjugate vaccines in regional mass vaccination campaigns to reduce further spread of those serogroups.


Subject(s)
Meningitis , Neisseria meningitidis, Serogroup C , Neisseria meningitidis , Humans , Burkina Faso/epidemiology , Serogroup , Neisseria meningitidis, Serogroup C/genetics , Disease Outbreaks , Neisseria meningitidis/genetics
2.
MMWR Morb Mortal Wkly Rep ; 73(5): 99-103, 2024 Feb 08.
Article in English | MEDLINE | ID: mdl-38329923

ABSTRACT

Meningococcal disease, caused by the bacterium Neisseria meningitidis, is a rare but life-threatening illness that requires prompt antibiotic treatment for patients and antibiotic prophylaxis for their close contacts. Historically, N. meningitidis isolates in the United States have been largely susceptible to the antibiotics recommended for prophylaxis, including ciprofloxacin. Since 2019, however, the number of meningococcal disease cases caused by ciprofloxacin-resistant strains has increased. Antibiotic prophylaxis with ciprofloxacin in areas with ciprofloxacin resistance might result in prophylaxis failure. Health departments should preferentially consider using antibiotics other than ciprofloxacin as prophylaxis for close contacts when both of the following criteria have been met in a local catchment area during a rolling 12-month period: 1) the reporting of two or more invasive meningococcal disease cases caused by ciprofloxacin-resistant strains, and 2) ≥20% of all reported invasive meningococcal disease cases are caused by ciprofloxacin-resistant strains. Other than ciprofloxacin, alternative recommended antibiotic options include rifampin, ceftriaxone, or azithromycin. Ongoing monitoring for antibiotic resistance of meningococcal isolates through surveillance and health care providers' reporting of prophylaxis failures will guide future updates to prophylaxis considerations and recommendations.


Subject(s)
Meningococcal Infections , Neisseria meningitidis , Humans , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/therapeutic use , Ceftriaxone/therapeutic use , Ciprofloxacin/pharmacology , Ciprofloxacin/therapeutic use , Meningococcal Infections/drug therapy , Meningococcal Infections/epidemiology , Meningococcal Infections/prevention & control , United States/epidemiology
4.
J Clin Microbiol ; 60(4): e0211121, 2022 04 20.
Article in English | MEDLINE | ID: mdl-35306833

ABSTRACT

To monitor the burden and changes in Haemophilus influenzae (Hi) disease, direct real-time PCR (drt-PCR) assays have been developed for Hi detection in monoplex form and its six serotypes in triplex form, directly from cerebrospinal fluid (CSF) specimens. These assays target the phoB gene for the species detection (Hi-phoB) and serotype-specific genes in region II of the capsule biosynthesis locus (Hi-abf and Hi-cde), identified through comparative analysis of Hi and non-Hi whole-genome sequences. The lower limit of detection (LLD) is 293 CFU/mL for the Hi-phoB assay and ranged from 11 to 130 CFU/mL for the triplex serotyping assays. Using culture as a reference method, the sensitivity and specificity of Hi-phoB, Hi-abf, and Hi-cde were 100%. Triplex serotyping assays also showed 100% agreement for each serotype compared to their corresponding monoplex serotyping assay. These highly sensitive and specific drt-PCR assays do not require DNA extraction and thereby reduce the time, cost, and handling required to process CSF specimens. Furthermore, triplex drt-PCR assays combine the detection of three serotypes in a single reaction, further improving testing efficiency, which is critical for laboratories that process high volumes of Hi specimens for surveillance and diagnostic purposes.


Subject(s)
Haemophilus influenzae , Multiplex Polymerase Chain Reaction , DNA , Haemophilus influenzae/genetics , Humans , Real-Time Polymerase Chain Reaction/methods , Sensitivity and Specificity , Serotyping/methods
5.
Nutrients ; 13(6)2021 Jun 15.
Article in English | MEDLINE | ID: mdl-34203983

ABSTRACT

Arabinoxylan (AX) is a structural polysaccharide found in wheat, rice and other cereal grains. Diets high in AX-containing fiber may promote gut health in obesity through prebiotic function. Thus, the impact of soluble AX isolated from rice bran fiber on human gut microbiota phylogenetic composition and short-chain fatty acid (SCFA) production patterns from normal-weight and overweight/obese subjects was investigated through in vitro fecal fermentation. Results showed that rice bran arabinoxylan modified the microbiota in fecal samples from both weight classes compared to control, significantly increasing Collinsella, Blautia and Bifidobacterium, and decreasing Sutterella, Bilophila and Parabacteroides. Rice bran AX also significantly increased total and individual SCFA contents (p < 0.05). This study suggests that rice bran AX may beneficially impact gut health in obesity through prebiotic activities.


Subject(s)
Feces/microbiology , Fermentation , Obesity/microbiology , Oryza/chemistry , Xylans/metabolism , Adult , Bacteria/classification , Diet , Dietary Carbohydrates , Dietary Fiber , Edible Grain , Fatty Acids, Volatile , Female , Gastrointestinal Microbiome , Humans , Male , Overweight , Phylogeny , Prebiotics , Triticum , Xylans/isolation & purification
6.
Clin Infect Dis ; 73(7): 1185-1193, 2021 10 05.
Article in English | MEDLINE | ID: mdl-33900407

ABSTRACT

BACKGROUND: Penicillin and ciprofloxacin are important for invasive meningococcal disease (IMD) management and prevention. IMD cases caused by penicillin- and ciprofloxacin-resistant Neisseria meningitidis containing a ROB-1 ß-lactamase gene (blaROB-1) and a mutated DNA gyrase gene (gyrA) have been recently reported in the United States. METHODS: We examined 2097 meningococcal genomes collected through US population-based surveillance from January 2011 to February 2020 to identify IMD cases caused by strains with blaROB-1- or gyrA-mediated resistance. Antimicrobial resistance was confirmed phenotypically. The US isolate genomes were compared to non-US isolate genomes containing blaROB-1. Interspecies transfer of ciprofloxacin resistance was assessed by comparing gyrA among Neisseria species. RESULTS: Eleven penicillin- and ciprofloxacin-resistant isolates were identified after December 2018; all were serogroup Y, sequence type 3587, clonal complex (CC) 23, and contained blaROB-1 and a T91I-containing gyrA allele. An additional 22 penicillin-resistant, blaROB-1- containing US isolates with wild-type gyrA were identified from 2013 to 2020. All 33 blaROB-1-containing isolates formed a single clade, along with 12 blaROB-1-containing isolates from 6 other countries. Two-thirds of blaROB-1-containing US isolates were from Hispanic individuals. Twelve additional ciprofloxacin-resistant isolates with gyrA T91 mutations were identified. Ciprofloxacin-resistant isolates belonged to 6 CCs and contained 10 unique gyrA alleles; 7 were similar or identical to alleles from Neisseria lactamica or Neisseria gonorrhoeae. CONCLUSIONS: Recent IMD cases caused by a dual resistant serogroup Y suggest changing antimicrobial resistance patterns in the United States. The emerging dual resistance is due to acquisition of ciprofloxacin resistance by ß-lactamase-containing N. meningitidis. Routine antimicrobial resistance surveillance will effectively monitor resistance changes and spread.


Subject(s)
Anti-Bacterial Agents , Ciprofloxacin , Drug Resistance, Bacterial , Meningococcal Infections , Neisseria meningitidis, Serogroup Y , Anti-Bacterial Agents/pharmacology , Ciprofloxacin/pharmacology , Humans , Meningococcal Infections/drug therapy , Microbial Sensitivity Tests , Neisseria meningitidis, Serogroup Y/drug effects , Neisseria meningitidis, Serogroup Y/genetics , Serogroup , United States/epidemiology , beta-Lactamases/genetics
7.
Microb Ecol ; 82(4): 845-858, 2021 Nov.
Article in English | MEDLINE | ID: mdl-33665722

ABSTRACT

Wine grape berries (Vitis spp.) harbor a wide variety of yeasts and filamentous fungi that impact grapevine health and the winemaking process. Identification of these fungi could be important for controlling and improving wine production. The use of high-throughput sequencing (HTS) strategies has enabled identification and quantification of bacterial and fungal species in vineyards. The aims of this study were to identify mycobiota from Cabernet Sauvignon and Zinfandel (V. vinifera), Carlos and Noble muscadines (V. rotundifolia), Cynthiana (V. aestivalis), and Vignoles hybrid (cross of different Vitis spp.) grapes, and investigate the effect of grape variety, location, and year on grape fungal communities. Grape berries were collected in 2016 and 2017 from four vineyards located in Arkansas. The HTS of the Internal Transcribed Spacer 1 region was used to identify grape indigenous epiphytic and endophytic fungal communities. The predominant genera identified on the Arkansas wine grapes were Uwebraunia, Zymoseptoria, Papiliotrema, Meyerozyma, Filobasidium, and Curvibasidium. Overall, the data suggested that grape fungal community distribution and relative abundance were influenced by grape variety, year, and location, but each was influenced to a different extent. Not only were grape mycobiota influenced by year, variety, and location but also it appeared that communities from the previous year impacted microbial communities the following year. For example, an increase of the mycoparasite Ampelomyces quisqualis was noticed in 2017 on grapes that carried the causal agent of powdery mildew, Erysiphe necator, in 2016, thus, amplifying the importance of vineyard microbiota knowledge for disease management and winemaking.


Subject(s)
Ascomycota , Vitis , Wine , Arkansas , Yeasts
8.
Microbiome ; 9(1): 38, 2021 02 02.
Article in English | MEDLINE | ID: mdl-33531080

ABSTRACT

BACKGROUND: Microbial endocrinology, which is the study of neuroendocrine-based interkingdom signaling, provides a causal mechanistic framework for understanding the bi-directional crosstalk between the host and microbiome, especially as regards the effect of stress on health and disease. The importance of the cecal microbiome in avian health is well-recognized, yet little is understood regarding the mechanisms underpinning the avian host-microbiome relationship. Neuroendocrine plasticity of avian tissues that are focal points of host-microbiome interaction, such as the gut and lung, has likewise received limited attention. Avian in vivo models that enable the study of the neuroendocrine dynamic between host and microbiome are needed. As such, we utilized Japanese quail (Coturnix japonica) that diverge in corticosterone response to stress to examine the relationship between stress-related neurochemical concentrations at sites of host-microbe interaction, such as the gut, and the cecal microbiome. RESULTS: Our results demonstrate that birds which contrast in corticosterone response to stress show profound separation in cecal microbial community structure as well as exhibit differences in tissue neurochemical concentrations and structural morphologies of the gut. Changes in neurochemicals known to be affected by the microbiome were also identified in tissues outside of the gut, suggesting a potential relationship in birds between the cecal microbiome and overall avian physiology. CONCLUSIONS: The present study provides the first evidence that the structure of the avian cecal microbial community is shaped by selection pressure on the bird for neuroendocrine response to stress. Identification of unique region-dependent neurochemical changes in the intestinal tract following stress highlights environmental stressors as potential drivers of microbial endocrinology-based mechanisms of avian host-microbiome dialogue. Together, these results demonstrate that tissue neurochemical concentrations in the avian gut may be related to the cecal microbiome and reveal the Japanese quail as a novel avian model in which to further examine the mechanisms underpinning these relationships. Video abstract.


Subject(s)
Coturnix/metabolism , Coturnix/microbiology , Endocrine System/metabolism , Endocrine System/microbiology , Host Microbial Interactions , Microbiota/physiology , Animals , Cecum/microbiology , Male , Models, Biological
9.
Microb Ecol ; 82(1): 73-86, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33515050

ABSTRACT

With the recent advancement of next-generation sequencing methods, there has been an increase in studies on identification of vineyard microbiota, winery-associated microbiota, and microbiota in wine fermentation. However, there have been few studies investigating the fungal microbiota of table grapes which present distinct spoilage and food safety challenges. The aims of this study were to identify and compare the impact of year, variety, and vineyard location on grape, leaf, and soil fungal communities of two varieties of table grapes, Faith and Gratitude, grown in two open-air vineyards and one high tunnel vineyard. The grape, leaf, and soil mycobiota were analyzed using high throughput amplicon sequencing of the ITS region. The sampling year and location of table grapes had an impact on grape, leaf, and soil mycobiota. Fungal diversity of grape, leaf, and soil was greater in 2017 than in 2016. Grape and leaf samples presented strong similarities in fungal communities with abundance of Sporidiobolaceae and Filobasidium in two vineyards and Cladosporium in another one. The high tunnel structure had distinct grape and leaf fungal communities compared to the two other vineyard locations. Mortierella was the predominant genus (27%) in soil samples for the three locations; however, genera of lower abundance varied between locations. These results provide extensive description of fungal communities in less-studied table grape vineyards and high tunnels, providing useful insight of potential threats and preventive strategies to help improve the production and marketability of table grapes.


Subject(s)
Mycobiome , Vitis , Arkansas , Plant Leaves , Soil
10.
Front Genet ; 11: 601870, 2020.
Article in English | MEDLINE | ID: mdl-33324449

ABSTRACT

Effective laboratory-based surveillance and public health response to bacterial meningitis depends on timely characterization of bacterial meningitis pathogens. Traditionally, characterizing bacterial meningitis pathogens such as Neisseria meningitidis (Nm) and Haemophilus influenzae (Hi) required several biochemical and molecular tests. Whole genome sequencing (WGS) has enabled the development of pipelines capable of characterizing the given pathogen with equivalent results to many of the traditional tests. Here, we present the Bacterial Meningitis Genomic Analysis Platform (BMGAP): a secure, web-accessible informatics platform that facilitates automated analysis of WGS data in public health laboratories. BMGAP is a pipeline comprised of several components, including both widely used, open-source third-party software and customized analysis modules for the specific target pathogens. BMGAP performs de novo draft genome assembly and identifies the bacterial species by whole-genome comparisons against a curated reference collection of 17 focal species including Nm, Hi, and other closely related species. Genomes identified as Nm or Hi undergo multi-locus sequence typing (MLST) and capsule characterization. Further typing information is captured from Nm genomes, such as peptides for the vaccine antigens FHbp, NadA, and NhbA. Assembled genomes are retained in the BMGAP database, serving as a repository for genomic comparisons. BMGAP's species identification and capsule characterization modules were validated using PCR and slide agglutination from 446 bacterial invasive isolates (273 Nm from nine different serogroups, 150 Hi from seven different serotypes, and 23 from nine other species) collected from 2017 to 2019 through surveillance programs. Among the validation isolates, BMGAP correctly identified the species for all 440 isolates (100% sensitivity and specificity) and accurately characterized all Nm serogroups (99% sensitivity and 98% specificity) and Hi serotypes (100% sensitivity and specificity). BMGAP provides an automated, multi-species analysis pipeline that can be extended to include additional analysis modules as needed. This provides easy-to-interpret and validated Nm and Hi genome analysis capacity to public health laboratories and collaborators. As the BMGAP database accumulates more genomic data, it grows as a valuable resource for rapid comparative genomic analyses during outbreak investigations.

11.
Sci Rep ; 10(1): 12514, 2020 07 27.
Article in English | MEDLINE | ID: mdl-32719325

ABSTRACT

Megaplasmids in Campylobacter spp. likely play important roles in antibiotic resistance, virulence, and horizontal gene transfer. In this study, megaplasmids pCJDM202 (119 kb) and pCJDM67L (116 kb) from C. jejuni strains WP2-202 and OD2-67, respectively, were sequenced and characterized. These megaplasmids contained genes for tetracycline resistance [tet(O)], the Type IV secretion system, conjugative transfer and the Type VI secretion system (T6SS). The T6SS genes in Campylobacter plasmids encoded genes and proteins that were similar to those identified in Campylobacter chromosomal DNA. When the megaplasmid pCJDM202 from C. jejuni WP2-202 was transferred via conjugation to C. jejuni NCTC11168 Nal+, transconconjugants acquired tetracycline resistance and enhanced cytotoxicity towards red blood cells. A T6SS mutant of strain WP2-202 was generated and designated Δhcp3; the mutant was significantly impaired in its ability to lyse red blood cells and survive in defibrinated blood. The cytotoxicity of Campylobacter strains towards the human embryonic kidney cell line HEK 293 was not impacted by the T6SS. In summary, the T6SS encoded by Campylobacter megaplasmids mediates lysis of RBCs and likely contributes to survival on retail meats where blood cells are abundant.


Subject(s)
Campylobacter jejuni/genetics , Campylobacter jejuni/isolation & purification , Chickens/microbiology , Gizzard, Avian/microbiology , Liver/microbiology , Plasmids/genetics , Type VI Secretion Systems/genetics , Animals , Cell Death , Cell Survival , Chromosomes, Bacterial/genetics , DNA, Bacterial/genetics , Erythrocytes/metabolism , Genome, Bacterial , HEK293 Cells , Hemolysis , Horses , Humans , Tetracycline Resistance
12.
Microbiol Resour Announc ; 9(7)2020 Feb 13.
Article in English | MEDLINE | ID: mdl-32054706

ABSTRACT

Four wild-type Campylobacter jejuni strains isolated from the cecal contents of broiler chickens were sequenced. The average genome size was 1,622,170 bp, with 1,667 to 1,761 coding sequences and 47 to 51 RNAs. Multiple genes encoding motility, intestinal colonization, toxin production, stress tolerance, and multidrug resistance were present in all the strains.

13.
Nutrients ; 11(2)2019 Jan 22.
Article in English | MEDLINE | ID: mdl-30678168

ABSTRACT

The human gut microbiota is considered as a crucial mediator between diet and gut homeostasis and body weight. The unique polyphenolic profile of sorghum bran may promote gastrointestinal health by modulating the microbiota. This study evaluated gut microbiota and modulation of short-chain fatty acids (SCFA) by sorghum bran polyphenols in in vitro batch fermentation derived from normal weight (NW, n = 11) and overweight/obese (OO, n = 11) subjects' fecal samples. Six separate treatments were applied on each batch fermentation: negative control (NC), fructooligosaccharides (FOS), black sorghum bran extract (BSE), sumac sorghum bran extract (SSE), FOS + BSE, or FOS + SSE; and samples were collected before and after 24 h. No significant differences in total and individual SCFA production were observed between NW and OO subjects. Differential responses to treatment according to weight class were observed in both phyla and genera. Sorghum bran polyphenols worked with FOS to enhance Bifidobacterium and Lactobacillus, and independently stimulated Roseburia and Prevotella (p < 0.05). Our results indicate that sorghum bran polyphenols have differential effects on gut health and may positively impact gut ecology, with responses varying depending on weight class.


Subject(s)
Feces/microbiology , Gastrointestinal Microbiome/drug effects , Overweight , Polyphenols/pharmacology , Sorghum , Adult , Antioxidants/metabolism , Antioxidants/pharmacology , Female , Fermentation , Humans , Male , Plant Extracts/chemistry , Plant Extracts/pharmacology , Polyphenols/chemistry , Young Adult
14.
Adv Food Nutr Res ; 87: 147-185, 2019.
Article in English | MEDLINE | ID: mdl-30678814

ABSTRACT

Fermented foods are currently experiencing a re-discovery, largely driven by numerous health benefits claims. While fermented dairy, beer, and wine (and other alcoholic fermented beverages) have been the subject of intensive research, other plant-based fermented foods that are in some case widely consumed (kimchi/sauerkraut, pickles, kombucha) have received less scientific attention. In this chapter, the current knowledge on the microbiology and potential health benefits of such plant-based fermented foods are presented. Kimchi is the most studied, characterized by primarily acidic fermentation by lactic acid bacteria. Anti-obesity and anti-hypertension properties have been reported for kimchi and other pickled vegetables. Kombucha is the most popular non-alcoholic fermented drink. Kombucha's microbiology is remarkable as it involves all fermenters described in known fermented foods: lactic acid bacteria, acetic acid bacteria, fungi, and yeasts. While kombucha is often hyped as a "super-food," only antioxidant and antimicrobial properties toward foodborne pathogens are well established; and it is unknown if these properties incur beneficial impact, even in vitro or in animal models. The mode of action that has been studied and demonstrated the most is the probiotic one. However, it can be expected that fermentation metabolites may be prebiotic, or influence host health directly. To conclude, plant-based fermented foods and drinks are usually safe products; few negative reports can be found, but more research, especially human dietary intervention studies, are warranted to substantiate any health claim.


Subject(s)
Beverages/microbiology , Fermented Foods , Food Microbiology , Vegetables/microbiology , Bacteria/classification , Bacteria/metabolism , Humans , Probiotics
15.
Front Microbiol ; 9: 2282, 2018.
Article in English | MEDLINE | ID: mdl-30356833

ABSTRACT

One of the unique features of actinomycetes, especially the genus Streptomyces, is the presence of linear plasmids. These range in size from 12 to 600 kb, and are often termed mega-plasmids. While many of the genes involved in secondary metabolite production reside in clusters on the chromosome, several studies have identified biosynthetic clusters on large linear plasmids that produce important secondary metabolites, including antibiotics. In this study, Pulse Field Gel Electrophoresis (PFGE) was used to screen 176 actinomycete isolates for the presence of plasmids; these bacterial strains were previously isolated from the Great Salt Plains of Oklahoma. Seventy-eight of the 176 actinomycete isolates (44%) contained plasmids. Several strains contained more than one plasmid, accounting for a total of 109 plasmids. Ten isolates showed extrachromosomal DNA larger than 200 kb, thus falling into the category of mega-plasmids. A subset of plasmids from 55 isolates was treated with S1 nuclease to determine topology; all plasmids examined appeared to be linear and ranged from ~55 to 400 kb. Eleven isolates were chosen for Whole Genome Next Generation Sequencing. From the 11 sequenced isolates, seven plasmids were partially assembled. While the majority of the genes identified on the plasmids coded for hypothetical proteins, others coded for general functions, stress response, and antibiotic and heavy metal resistance. Draft genome sequences of two mega-plasmid-bearing Streptomyces sp. strains, BF-3 and 4F, revealed the presence of genes involved in antibiotic production, antibiotic, and heavy metal resistance, osmoregulation, and stress response, which likely facilitate their survival in this extreme halophilic environment. To our knowledge, this is the first study to explore plasmids harbored by actinomycetes isolated from the Great Salt Plains of Oklahoma.

16.
Front Microbiol ; 9: 2167, 2018.
Article in English | MEDLINE | ID: mdl-30258424

ABSTRACT

Campylobacter jejuni and Campylobacter coli are two of the major causes of foodborne illness. In this study, 29 plasmids isolated from 20 retail meat isolates of Campylobacter jejuni and Campylobacter coli were fully-sequenced individually or as a part of a whole genome sequencing approach. The fully-sequenced plasmids ranged in size from 3 to 119 kb. Molecular characterization of the sequenced plasmids was based on pangenomic analysis and types of genes present on these plasmids and similar ones from GenBank. The plasmids were categorized into four different groups. These groups include type-1 that consisted mainly of pTet plasmids with the tetO gene, type-2 plasmids commonly found in C. coli strains, type-3 which has pVir plasmids, and type-4 that consisted mainly of smaller plasmids. The type-2 plasmids were unique, common among C. coli strains, and carried several conjugative transfer genes. The type-2 plasmids were most similar to a plasmid from Helicobacter pullorum. Maximum parsimony analysis and NeighborNet analysis were used to assess the phylogenetic relatedness among the 29 plasmid sequences presented in this study in addition to the other 104 plasmid sequences of Campylobacter species available in GenBank to date. Results from MP analysis revealed multiple lineages among Campylobacter plasmids which was supported by NeighborNet analysis. Clustering of plasmids did not conform to species-specific clades which suggested an intra-species dissemination of plasmids among Campylobacter species. To our knowledge, this is the first extensive phylogenetic analysis of Campylobacter plasmids sequenced to date.

17.
J Nutr Biochem ; 59: 160-172, 2018 09.
Article in English | MEDLINE | ID: mdl-30055451

ABSTRACT

Tart cherries have been reported to exert potential health benefits attributed to their specific and abundant polyphenol content. However, there is a need to study the impact and fate of tart cherries polyphenols in the gut microbiota. Here, tart cherries, pure polyphenols (and apricots) were submitted to in vitro bacterial fermentation assays and assessed through 16S rRNA gene sequence sequencing and metabolomics. A short-term (5 days, 8 oz. daily) human dietary intervention study was also conducted for microbiota analyses. Tart cherry concentrate juices were found to contain expected abundances of anthocyanins (cyanidin-glycosylrutinoside) and flavonoids (quercetin-rutinoside) and high amounts of chlorogenic and neochlorogenic acids. Targeted metabolomics confirmed that gut microbes were able to degrade those polyphenols mainly to 4-hydroxyphenylpropionic acids and to lower amounts of epicatechin and 4-hydroxybenzoic acids. Tart cherries were found to induce a large increase of Bacteroides in vitro, likely due to the input of polysaccharides, but prebiotic effect was also suggested by Bifidobacterium increase from chlorogenic acid. In the human study, two distinct and inverse responses to tart cherry consumption were associated with initial levels of Bacteroides. High-Bacteroides individuals responded with a decrease in Bacteroides and Bifidobacterium, and an increase of Lachnospiraceae, Ruminococcus and Collinsella. Low-Bacteroides individuals responded with an increase in Bacteroides or Prevotella and Bifidobacterium, and a decrease of Lachnospiraceae, Ruminococcus and Collinsella. These data confirm that gut microbiota metabolism, in particular the potential existence of different metabotypes, needs to be considered in studies attempting to link tart cherries consumption and health.


Subject(s)
Gastrointestinal Microbiome/drug effects , Gastrointestinal Microbiome/physiology , Polyphenols/pharmacology , Prunus avium/chemistry , Adult , Bifidobacterium/drug effects , Bifidobacterium/genetics , Female , Fermentation , Fruit and Vegetable Juices , Gastrointestinal Microbiome/genetics , Humans , Male , Phenols/metabolism , Polyphenols/analysis , Polyphenols/pharmacokinetics
18.
Genome Announc ; 6(14)2018 Apr 05.
Article in English | MEDLINE | ID: mdl-29622611

ABSTRACT

Draft genome sequences of megaplasmid-bearing Streptomyces sp. strains BF-3 and 4F, isolated from the Great Salt Plains of Oklahoma, showed genome sizes of 7,950,134 and 7,550,992 bp, respectively. Both genomes revealed the presence of genes involved in osmoregulation and stress response, potentially helping their survival in such an extreme environment.

19.
Front Microbiol ; 9: 2951, 2018.
Article in English | MEDLINE | ID: mdl-30631306

ABSTRACT

Aerotolerance in the microaerophilic species Campylobacter was previously reported and could increase bacterial survival and transmission in foods during stressful processing and storage conditions. In this study, 167 Campylobacter isolates (76 C. jejuni and 91 C. coli) were screened for aerotolerance; these strains were previously isolated from retail chicken meat, chicken livers, chicken gizzards, turkey, pork, and beef liver samples. Bacterial cultures were incubated aerobically in Mueller Hinton broth with agitation and viable cell counts were taken at 0, 6, 12, and 24 h. Approximately 47% of the screened Campylobacter isolates were aerotolerant (viable after a 12-h aerobic incubation period), whereas 24% were hyper-aerotolerant (viable after a 24-h aerobic incubation). A greater prevalence of aerotolerant strains (80%) was found among C. coli isolates as compared to C. jejuni isolates (6%). Differences in the oxidative stress response related genes were detected among C. jejuni and C. coli isolates when comparative genomics was used to analyze 17 Whole Genome Sequenced (WGS) strains from our laboratory. Genes encoding putative transcriptional regulator proteins and a catalase-like heme binding protein were found in C. coli genomes, but were absent in the genomes of C. jejuni. PCR screening showed the presence of a catalase-like protein gene in 75% (68/91) of C. coli strains, which was absent in all tested C. jejuni strains. While about 79% (30/38) of the hyper-aerotolerant C. coli strains harbored the catalase-like protein gene, the gene was also present in a number of the aerosensitive strains. The Catalase like protein gene was found to be expressed in both aerobic and microaerobic conditions with a 2-fold higher gene expression detected in aerobic conditions for an aerosensitive strain. However, the exact function of the gene remains unclear and awaits further investigation. In conclusion, aerotolerant Campylobacter strains (especially C. coli) are prevalent in various retail meats. Further studies are needed to investigate whether the genes encoding catalase-like heme binding protein and putative transcriptional regulators in C. coli strains are involved in stress response.

20.
Genome Announc ; 5(49)2017 Dec 07.
Article in English | MEDLINE | ID: mdl-29217797

ABSTRACT

Complete genome sequences of Campylobacter coli strains WA333, YF2105, BG2108, MG1116, and BP3183 and Campylobacter jejuni strain IF1100 isolated from retail chicken liver showed the presence of 1,841,551-, 1,687,232-, 1,695,638-, 1,665,146-, 1,695,360-, and 1,744,171-bp circular chromosomes, respectively. These isolates also contained plasmids ranging in size from 5,209 to 55,122 bp.

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