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Sample records for neisseriaceae

  1. Structural analysis of haemoglobin binding by HpuA from the Neisseriaceae family

    PubMed Central

    Wong, Chi T.; Xu, Yingqi; Gupta, Akshari; Garnett, James A.; Matthews, Steve J.; Hare, Stephen A.

    2015-01-01

    The Neisseriaceae family of bacteria causes a range of diseases including meningitis, septicaemia, gonorrhoea and endocarditis, and extracts haem from haemoglobin as an important iron source within the iron-limited environment of its human host. Herein we report crystal structures of apo- and haemoglobin-bound HpuA, an essential component of this haem import system. The interface involves long loops on the bacterial receptor that present hydrophobic side chains for packing against the surface of haemoglobin. Interestingly, our structural and biochemical analyses of Kingella denitrificans and Neisseria gonorrhoeae HpuA mutants, although validating the interactions observed in the crystal structure, show how Neisseriaceae have the fascinating ability to diversify functional sequences and yet retain the haemoglobin binding function. Our results present the first description of HpuA's role in direct binding of haemoglobin. PMID:26671256

  2. Structural analysis of haemoglobin binding by HpuA from the Neisseriaceae family.

    PubMed

    Wong, Chi T; Xu, Yingqi; Gupta, Akshari; Garnett, James A; Matthews, Steve J; Hare, Stephen A

    2015-12-16

    The Neisseriaceae family of bacteria causes a range of diseases including meningitis, septicaemia, gonorrhoea and endocarditis, and extracts haem from haemoglobin as an important iron source within the iron-limited environment of its human host. Herein we report crystal structures of apo- and haemoglobin-bound HpuA, an essential component of this haem import system. The interface involves long loops on the bacterial receptor that present hydrophobic side chains for packing against the surface of haemoglobin. Interestingly, our structural and biochemical analyses of Kingella denitrificans and Neisseria gonorrhoeae HpuA mutants, although validating the interactions observed in the crystal structure, show how Neisseriaceae have the fascinating ability to diversify functional sequences and yet retain the haemoglobin binding function. Our results present the first description of HpuA's role in direct binding of haemoglobin.

  3. Diagnostic value of interactions between members of the family Neisseriaceae and lectins.

    PubMed Central

    Doyle, R J; Nedjat-Haiem, F; Keller, K F; Frasch, C E

    1984-01-01

    The lectin slide agglutination test for Neisseria gonorrhoeae has been modified and improved. Results show that wheat germ agglutinin and soybean lectin agglutinate 100% (193 of 193 tested) of clinical isolates of N. gonorrhoeae. Lectin-reactive meningococci can be readily identified by the hydrolysis of gamma-glutamyl-beta-naphthylamide. Branhamella catarrhalis, Neisseria lactamica, Neisseria sicca, Neisseria subflava, Neisseria perflava, and meningococcal serogroups A, B, C, X, Y, and Z do not interfere with the positive identification of N. gonorrhoeae. The frequently encountered problem of autoagglutination of members of the family Neisseriaceae may be circumvented by a short treatment of cellular suspensions with DNase. Based on agglutination assays, the enzyme treatment did not result in a loss of wheat germ agglutinin receptors from the bacteria. The lectin agglutination test, coupled with the gamma-glutamyl aminopeptidase assay, is proposed as a rapid and accurate means of identifying clinical isolates of gonococci. PMID:6546936

  4. Diagnostics of neisseriaceae and moraxellaceae by ribosomal DNA sequencing: ribosomal differentiation of medical microorganisms.

    PubMed

    Harmsen, D; Singer, C; Rothgänger, J; Tønjum, T; de Hoog, G S; Shah, H; Albert, J; Frosch, M

    2001-03-01

    Fast and reliable identification of microbial isolates is a fundamental goal of clinical microbiology. However, in the case of some fastidious gram-negative bacterial species, classical phenotype identification based on either metabolic, enzymatic, or serological methods is difficult, time-consuming, and/or inadequate. 16S or 23S ribosomal DNA (rDNA) bacterial sequencing will most often result in accurate speciation of isolates. Therefore, the objective of this study was to find a hypervariable rDNA stretch, flanked by strongly conserved regions, which is suitable for molecular species identification of members of the Neisseriaceae and Moraxellaceae. The inter- and intrageneric relationships were investigated using comparative sequence analysis of PCR-amplified partial 16S and 23S rDNAs from a total of 94 strains. When compared to the type species of the genera Acinetobacter, Moraxella, and Neisseria, an average of 30 polymorphic positions was observed within the partial 16S rDNA investigated (corresponding to Escherichia coli positions 54 to 510) for each species and an average of 11 polymorphic positions was observed within the 202 nucleotides of the 23S rDNA gene (positions 1400 to 1600). Neisseria macacae and Neisseria mucosa subsp. mucosa (ATCC 19696) had identical 16S and 23S rDNA sequences. Species clusters were heterogeneous in both genes in the case of Acinetobacter lwoffii, Moraxella lacunata, and N. mucosa. Neisseria meningitidis isolates failed to cluster only in the 23S rDNA subset. Our data showed that the 16S rDNA region is more suitable than the partial 23S rDNA for the molecular diagnosis of Neisseriaceae and Moraxellaceae and that a reference database should include more than one strain of each species. All sequence chromatograms and taxonomic and disease-related information are available as part of our ribosomal differentiation of medical microorganisms (RIDOM) web-based service (http://www.ridom.hygiene.uni-wuerzburg.de/). Users can submit a

  5. Identification of type 4 pili in Kingella denitrificans.

    PubMed Central

    Weir, S; Marrs, C F

    1992-01-01

    Kingella denitrificans is an occasionally pathogenic member of the family Neisseriaceae and is a member of the normal respiratory flora. Electron microscopy, colony morphology types, DNA transformation patterns, and immunoblots suggest that K. denitrificans and K. kingae have type 4 pili. This was confirmed by N-terminal amino acid sequencing for K. denitrificans. Images PMID:1353484

  6. The microbial ecology of processing equipment in different fish industries-analysis of the microflora during processing and following cleaning and disinfection.

    PubMed

    Bagge-Ravn, Dorthe; Ng, Yin; Hjelm, Mette; Christiansen, Jesper N; Johansen, Charlotte; Gram, Lone

    2003-11-01

    The microflora adhering to the processing equipment during production and after cleaning and disinfecting procedures was identified in four different processing plants. A total of 1009 microorganisms was isolated from various-agar plates and identified. A stepwise procedure using simple phenotypic tests was used to identify the isolates and proved a fast way to group a large collection of microorganisms. Pseudomonas, Neisseriaceae, Enterobactericeae, Coryneform, Acinetobacter and lactic acid bacteria dominated the microflora of cold-smoked salmon plants, whereas the microflora in a plant processing semi-preserved herring consisted of Pseudomonas, Alcaligenes and Enterobactericeae. Psychrobacter, Staphylococcus and yeasts were found in a caviar processing plant. Overall, many microorganisms that are often isolated from fish were also isolated from the fish processing plants. However, some selection depending on processing parameters occurred, since halo- and osmo-tolerant organisms dominated in the caviar processing. After cleaning and disinfection, yeasts, Pseudomonas, Neisseriaceae and Alcaligenes remained in smokehouses, yeasts and Pseudomonas in the herring plant and Pseudomonas, Staphylococcus and yeasts in the caviar plant. The dominant adhering organisms after cleaning and disinfection were pseudomonads and yeasts independently of the microflora during processing. Knowledge of the adhering microflora is essential in the Good Hygienic Practises programme of food processing plants, as the development and design of improved cleaning and disinfecting procedures should target the microorganisms persisting and potentially contaminating the product. PMID:14527796

  7. Environmental arsenic exposure and microbiota in induced sputum.

    PubMed

    White, Allison G; Watts, George S; Lu, Zhenqiang; Meza-Montenegro, Maria M; Lutz, Eric A; Harber, Philip; Burgess, Jefferey L

    2014-02-21

    Arsenic exposure from drinking water is associated with adverse respiratory outcomes, but it is unknown whether arsenic affects pulmonary microbiota. This exploratory study assessed the effect of exposure to arsenic in drinking water on bacterial diversity in the respiratory tract of non-smokers. Induced sputum was collected from 10 subjects with moderate mean household water arsenic concentration (21.1 ± 6.4 ppb) and 10 subjects with low household water arsenic (2.4 ± 0.8 ppb). To assess microbiota in sputum, the V6 hypervariable region amplicons of bacterial 16s rRNA genes were sequenced using the Ion Torrent Personal Genome Machine. Microbial community differences between arsenic exposure groups were evaluated using QIIME and Metastats. A total of 3,920,441 sequence reads, ranging from 37,935 to 508,787 per sample for 316 chips after QIIME quality filtering, were taxonomically classified into 142 individual genera and five phyla. Firmicutes (22%), Proteobacteria (17%) and Bacteriodetes (12%) were the main phyla in all samples, with Neisseriaceae (15%), Prevotellaceae (12%) and Veillonellacea (7%) being most common at the genus level. Some genera, including Gemella, Lactobacillales, Streptococcus, Neisseria and Pasteurellaceae were elevated in the moderate arsenic exposure group, while Rothia, Prevotella, Prevotellaceae Fusobacterium and Neisseriaceae were decreased, although none of these differences was statistically significant. Future studies with more participants and a greater range of arsenic exposure are needed to further elucidate the effects of drinking water arsenic consumption on respiratory microbiota.

  8. Environmental Arsenic Exposure and Microbiota in Induced Sputum

    PubMed Central

    White, Allison G.; Watts, George S.; Lu, Zhenqiang; Meza-Montenegro, Maria M.; Lutz, Eric A.; Harber, Philip; Burgess, Jefferey L.

    2014-01-01

    Arsenic exposure from drinking water is associated with adverse respiratory outcomes, but it is unknown whether arsenic affects pulmonary microbiota. This exploratory study assessed the effect of exposure to arsenic in drinking water on bacterial diversity in the respiratory tract of non-smokers. Induced sputum was collected from 10 subjects with moderate mean household water arsenic concentration (21.1 ± 6.4 ppb) and 10 subjects with low household water arsenic (2.4 ± 0.8 ppb). To assess microbiota in sputum, the V6 hypervariable region amplicons of bacterial 16s rRNA genes were sequenced using the Ion Torrent Personal Genome Machine. Microbial community differences between arsenic exposure groups were evaluated using QIIME and Metastats. A total of 3,920,441 sequence reads, ranging from 37,935 to 508,787 per sample for 316 chips after QIIME quality filtering, were taxonomically classified into 142 individual genera and five phyla. Firmicutes (22%), Proteobacteria (17%) and Bacteriodetes (12%) were the main phyla in all samples, with Neisseriaceae (15%), Prevotellaceae (12%) and Veillonellacea (7%) being most common at the genus level. Some genera, including Gemella, Lactobacillales, Streptococcus, Neisseria and Pasteurellaceae were elevated in the moderate arsenic exposure group, while Rothia, Prevotella, Prevotellaceae Fusobacterium and Neisseriaceae were decreased, although none of these differences was statistically significant. Future studies with more participants and a greater range of arsenic exposure are needed to further elucidate the effects of drinking water arsenic consumption on respiratory microbiota. PMID:24566055

  9. 16S rRNA Amplicon Sequencing Demonstrates that Indoor-Reared Bumblebees (Bombus terrestris) Harbor a Core Subset of Bacteria Normally Associated with the Wild Host

    PubMed Central

    Meeus, Ivan; Parmentier, Laurian; Billiet, Annelies; Maebe, Kevin; Van Nieuwerburgh, Filip; Deforce, Dieter; Wäckers, Felix; Vandamme, Peter; Smagghe, Guy

    2015-01-01

    A MiSeq multiplexed 16S rRNA amplicon sequencing of the gut microbiota of wild and indoor-reared Bombus terrestris (bumblebees) confirmed the presence of a core set of bacteria, which consisted of Neisseriaceae (Snodgrassella), Orbaceae (Gilliamella), Lactobacillaceae (Lactobacillus), and Bifidobacteriaceae (Bifidobacterium). In wild B. terrestris we detected several non-core bacteria having a more variable prevalence. Although Enterobacteriaceae are unreported by non next-generation sequencing studies, it can become a dominant gut resident. Furthermore the presence of some non-core lactobacilli were associated with the relative abundance of bifidobacteria. This association was not observed in indoor-reared bumblebees lacking the non-core bacteria, but having a more standardized microbiota compared to their wild counterparts. The impact of the bottleneck microbiota of indoor-reared bumblebees when they are used in the field for pollination purpose is discussed. PMID:25923917

  10. 16S rRNA Amplicon Sequencing Demonstrates that Indoor-Reared Bumblebees (Bombus terrestris) Harbor a Core Subset of Bacteria Normally Associated with the Wild Host.

    PubMed

    Meeus, Ivan; Parmentier, Laurian; Billiet, Annelies; Maebe, Kevin; Van Nieuwerburgh, Filip; Deforce, Dieter; Wäckers, Felix; Vandamme, Peter; Smagghe, Guy

    2015-01-01

    A MiSeq multiplexed 16S rRNA amplicon sequencing of the gut microbiota of wild and indoor-reared Bombus terrestris (bumblebees) confirmed the presence of a core set of bacteria, which consisted of Neisseriaceae (Snodgrassella), Orbaceae (Gilliamella), Lactobacillaceae (Lactobacillus), and Bifidobacteriaceae (Bifidobacterium). In wild B. terrestris we detected several non-core bacteria having a more variable prevalence. Although Enterobacteriaceae are unreported by non next-generation sequencing studies, it can become a dominant gut resident. Furthermore the presence of some non-core lactobacilli were associated with the relative abundance of bifidobacteria. This association was not observed in indoor-reared bumblebees lacking the non-core bacteria, but having a more standardized microbiota compared to their wild counterparts. The impact of the bottleneck microbiota of indoor-reared bumblebees when they are used in the field for pollination purpose is discussed.

  11. The molecular mechanism of Zinc acquisition by the neisserial outer-membrane transporter ZnuD

    NASA Astrophysics Data System (ADS)

    Calmettes, Charles; Ing, Christopher; Buckwalter, Carolyn M.; El Bakkouri, Majida; Chieh-Lin Lai, Christine; Pogoutse, Anastassia; Gray-Owen, Scott D.; Pomès, Régis; Moraes, Trevor F.

    2015-08-01

    Invading bacteria from the Neisseriaceae, Acinetobacteriaceae, Bordetellaceae and Moraxellaceae families express the conserved outer-membrane zinc transporter zinc-uptake component D (ZnuD) to overcome nutritional restriction imposed by the host organism during infection. Here we demonstrate that ZnuD is required for efficient systemic infections by the causative agent of bacterial meningitis, Neisseria meningitidis, in a mouse model. We also combine X-ray crystallography and molecular dynamics simulations to gain insight into the mechanism of zinc recognition and transport across the bacterial outer-membrane by ZnuD. Because ZnuD is also considered a promising vaccine candidate against N. meningitidis, we use several ZnuD structural intermediates to map potential antigenic epitopes, and propose a mechanism by which ZnuD can maintain high sequence conservation yet avoid immune recognition by altering the conformation of surface-exposed loops.

  12. Role of porin proteins in acquisition of transferrin iron by enteropathogens.

    PubMed

    Sandrini, Sara; Masania, Rikesh; Zia, Fatima; Haigh, Richard; Freestone, Primrose

    2013-12-01

    Acquisition of iron from key innate immune defence proteins such as transferrin (Tf) and lactoferrin is an important mechanism by which pathogenic bacteria obtain essential iron for growth within their host. Bacterial species that do not produce siderophores often use specific Tf-binding proteins, the best characterized being the Neisseriaceae-type Tf-binding proteins TbpA and TbpB. Previous work from our laboratory has shown that siderophore-producing enteric species such as Escherichia coli also readily bind Tf, although no genomic evidence exists for Tbp-like Tf-binding proteins. Application of proteomic analyses and molecular mutagenesis strategies to an enteropathogenic E. coli identified the OmpA and OmpC porins as Tf-binding proteins. Mutagenesis of the ompA or ompC genes affected E. coli Tf binding and, furthermore, compromised the ability of the ompA mutant to respond to growth promotion by certain catecholamine stress hormones. Evidence was also found to implicate the OmpA porin as an entry point for catecholamine stress hormones. Further proteomic analyses in other bacterial pathogens revealed wide-scale involvement of porins in Tf binding: Salmonella typhimurium (OmpC), and Shigella sonnei, Shigella flexneri and Shigella boydii (OmpC and/or OmpA). This study shows that in addition to their existing housekeeping functions, the Gram-negative porin family of proteins can also act as Tf-capture proteins for those bacteria that lack the classical Neisseriaceae-type Tf-binding proteins.

  13. Crenobacter luteus gen. nov., sp. nov., isolated from a hot spring.

    PubMed

    Dong, Lei; Ming, Hong; Zhou, En-Min; Yin, Yi-Rui; Liu, Lan; Feng, Hui-Geng; Xian, Wen-Dong; Nie, Guo-Xing; Li, Wen-Jun

    2015-01-01

    A slightly thermophilic, Gram-staining-negative and strictly aerobic bacteria, designated strain YIM 78141(T), was isolated from a sediment sample collected at Hehua hot spring, Tengchong, Yunnan province, south-west China. Cells of the strain were short-rod-shaped and colonies were yellowish and circular. The strain grew at pH 6.0-10.0 (optimum, pH 8.0-9.0) and 10-55 °C (optimum, 40-50 °C). Phylogenetic analyses based on 16S rRNA gene sequence comparison demonstrated that strain YIM 78141(T) belongs to the family Neisseriaceae, and strain YIM 78141(T) also showed low levels of 16S rRNA gene sequence similarity (below 93.4%) with all other genera in this family. The only quinone was ubiquinone 8 and the genomic DNA G+C content was 67.3 mol%. Major fatty acids (>5%) were C12:0, C16:0, C18:1ω7c and summed feature 3. The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine, phospholipids of unknown structure containing aminoglycophospholipid and three unidentified polar lipids. On the basis of the morphological, physiological and biochemical characteristics as well as genotypic data, this strain should be classified as a representative of a novel genus and species of the family Neisseriaceae, for which the name Crenobacter luteus gen. nov., sp. nov. is proposed. The type strain is YIM 78141(T) ( =BCRC 80650(T) =KCTC 32558(T) =DSM 27258(T)).

  14. Biofouling characteristics and identification of preponderant bacteria at different nutrient levels in batch tests of a recirculating cooling water system.

    PubMed

    Liu, Fang; Zhao, Chao-Cheng; Xia, Lu; Yang, Fei; Chang, Xin; Wang, Yong-Qiang

    2011-01-01

    Understanding the influence of nutrient levels on biofouling control is an important requirement for management strategies in a recirculating cooling water system. Nutrient limitation may be one way to control biofouling development without increasing biocide dosing. Therefore, this study was carried out to investigate the effects of nutrient levels on biofouling characteristics and to identify the preponderant bacteria in the batch tests with a simulated cooling water system. The biofouling characteristics were assessed by varying the biofoulant mass and the bacteria respiratory activity, which was estimated by measuring oxygen uptake rates. According to the results obtained in nutrient factor experiments, the biofouling could be better controlled at carbon, nitrogen and phosphorus concentrations of 30 mg N/L, 8 mg N/L and 1.0 mg P/L, respectively. Increasing carbon concentrations shortened the biofouling initial growth period and resulted in higher biofoulant mass. The preponderant bacteria strains involved in biofouling under two culture conditions were identified by applying both physiological and biochemical tests and further molecular biology techniques with phylogenetic affiliation analysis. Enterobacter (family Enterobacteriaceae), Staphylococcus (family Micrococcaceae), Bacillus (family Bacillaceae), Proteus (family Enterobacteriaceae), Neisseria (family Neisseriaceae) and Pseudomonas (family Pseudomonadaceae) were dominant in the conditions of lower carbon concentration (30 mg/L). Enterobacter are autotrophs, but the other five bacteria are all heterotrophs. In the conditions of higher carbon concentration (70 mg/L), Klebsiella (family Enterobacteriaceae), Enterobacter and Microbacterium (family Microbacteriaceae) were dominant; Enterobacter and Microbacterium are heterotrophs.

  15. Relationship between honeybee nutrition and their microbial communities.

    PubMed

    Saraiva, Miriane Acosta; Zemolin, Ana Paula Pegoraro; Franco, Jeferson Luis; Boldo, Juliano Tomazzoni; Stefenon, Valdir Marcos; Triplett, Eric W; de Oliveira Camargo, Flávio Anastácio; Roesch, Luiz Fernando Wurdig

    2015-04-01

    The microbiota and the functional genes actively involved in the process of breakdown and utilization of pollen grains in beebread and bee guts are not yet understood. The aim of this work was to assess the diversity and community structure of bacteria and archaea in Africanized honeybee guts and beebread as well as to predict the genes involved in the microbial bioprocessing of pollen using state of the art 'post-light' based sequencing technology. A total of 11 bacterial phyla were found within bee guts and 10 bacterial phyla were found within beebread. Although the phylum level comparison shows most phyla in common, a deeper phylogenetic analysis showed greater variation of taxonomic composition. The families Enterobacteriaceae, Ricketsiaceae, Spiroplasmataceae and Bacillaceae, were the main groups responsible for the specificity of the bee gut while the main families responsible for the specificity of the beebread were Neisseriaceae, Flavobacteriaceae, Acetobacteraceae and Lactobacillaceae. In terms of microbial community structure, the analysis showed that the communities from the two environments were quite different from each other with only 7 % of species-level taxa shared between bee gut and beebread. The results indicated the presence of a highly specialized and well-adapted microbiota within each bee gut and beebread. The beebread community included a greater relative abundance of genes related to amino acid, carbohydrate, and lipid metabolism, suggesting that pollen biodegradation predominantly occurs in the beebread. These results suggests a complex and important relationship between honeybee nutrition and their microbial communities. PMID:25601048

  16. Microbial gut diversity of Africanized and European honey bee larval instars.

    PubMed

    Vojvodic, Svjetlana; Rehan, Sandra M; Anderson, Kirk E

    2013-01-01

    The first step in understanding gut microbial ecology is determining the presence and potential niche breadth of associated microbes. While the core gut bacteria of adult honey bees is becoming increasingly apparent, there is very little and inconsistent information concerning symbiotic bacterial communities in honey bee larvae. The larval gut is the target of highly pathogenic bacteria and fungi, highlighting the need to understand interactions between typical larval gut flora, nutrition and disease progression. Here we show that the larval gut is colonized by a handful of bacterial groups previously described from guts of adult honey bees or other pollinators. First and second larval instars contained almost exclusively Alpha 2.2, a core Acetobacteraceae, while later instars were dominated by one of two very different Lactobacillus spp., depending on the sampled site. Royal jelly inhibition assays revealed that of seven bacteria occurring in larvae, only one Neisseriaceae and one Lactobacillus sp. were inhibited. We found both core and environmentally vectored bacteria with putatively beneficial functions. Our results suggest that early inoculation by Acetobacteraceae may be important for microbial succession in larvae. This assay is a starting point for more sophisticated in vitro models of nutrition and disease resistance in honey bee larvae. PMID:23991051

  17. Microbial Gut Diversity of Africanized and European Honey Bee Larval Instars

    PubMed Central

    Vojvodic, Svjetlana; Rehan, Sandra M.; Anderson, Kirk E.

    2013-01-01

    The first step in understanding gut microbial ecology is determining the presence and potential niche breadth of associated microbes. While the core gut bacteria of adult honey bees is becoming increasingly apparent, there is very little and inconsistent information concerning symbiotic bacterial communities in honey bee larvae. The larval gut is the target of highly pathogenic bacteria and fungi, highlighting the need to understand interactions between typical larval gut flora, nutrition and disease progression. Here we show that the larval gut is colonized by a handful of bacterial groups previously described from guts of adult honey bees or other pollinators. First and second larval instars contained almost exclusively Alpha 2.2, a core Acetobacteraceae, while later instars were dominated by one of two very different Lactobacillus spp., depending on the sampled site. Royal jelly inhibition assays revealed that of seven bacteria occurring in larvae, only one Neisseriaceae and one Lactobacillus sp. were inhibited. We found both core and environmentally vectored bacteria with putatively beneficial functions. Our results suggest that early inoculation by Acetobacteraceae may be important for microbial succession in larvae. This assay is a starting point for more sophisticated in vitro models of nutrition and disease resistance in honey bee larvae. PMID:23991051

  18. Relationship between honeybee nutrition and their microbial communities.

    PubMed

    Saraiva, Miriane Acosta; Zemolin, Ana Paula Pegoraro; Franco, Jeferson Luis; Boldo, Juliano Tomazzoni; Stefenon, Valdir Marcos; Triplett, Eric W; de Oliveira Camargo, Flávio Anastácio; Roesch, Luiz Fernando Wurdig

    2015-04-01

    The microbiota and the functional genes actively involved in the process of breakdown and utilization of pollen grains in beebread and bee guts are not yet understood. The aim of this work was to assess the diversity and community structure of bacteria and archaea in Africanized honeybee guts and beebread as well as to predict the genes involved in the microbial bioprocessing of pollen using state of the art 'post-light' based sequencing technology. A total of 11 bacterial phyla were found within bee guts and 10 bacterial phyla were found within beebread. Although the phylum level comparison shows most phyla in common, a deeper phylogenetic analysis showed greater variation of taxonomic composition. The families Enterobacteriaceae, Ricketsiaceae, Spiroplasmataceae and Bacillaceae, were the main groups responsible for the specificity of the bee gut while the main families responsible for the specificity of the beebread were Neisseriaceae, Flavobacteriaceae, Acetobacteraceae and Lactobacillaceae. In terms of microbial community structure, the analysis showed that the communities from the two environments were quite different from each other with only 7 % of species-level taxa shared between bee gut and beebread. The results indicated the presence of a highly specialized and well-adapted microbiota within each bee gut and beebread. The beebread community included a greater relative abundance of genes related to amino acid, carbohydrate, and lipid metabolism, suggesting that pollen biodegradation predominantly occurs in the beebread. These results suggests a complex and important relationship between honeybee nutrition and their microbial communities.

  19. Microbial gut diversity of Africanized and European honey bee larval instars.

    PubMed

    Vojvodic, Svjetlana; Rehan, Sandra M; Anderson, Kirk E

    2013-01-01

    The first step in understanding gut microbial ecology is determining the presence and potential niche breadth of associated microbes. While the core gut bacteria of adult honey bees is becoming increasingly apparent, there is very little and inconsistent information concerning symbiotic bacterial communities in honey bee larvae. The larval gut is the target of highly pathogenic bacteria and fungi, highlighting the need to understand interactions between typical larval gut flora, nutrition and disease progression. Here we show that the larval gut is colonized by a handful of bacterial groups previously described from guts of adult honey bees or other pollinators. First and second larval instars contained almost exclusively Alpha 2.2, a core Acetobacteraceae, while later instars were dominated by one of two very different Lactobacillus spp., depending on the sampled site. Royal jelly inhibition assays revealed that of seven bacteria occurring in larvae, only one Neisseriaceae and one Lactobacillus sp. were inhibited. We found both core and environmentally vectored bacteria with putatively beneficial functions. Our results suggest that early inoculation by Acetobacteraceae may be important for microbial succession in larvae. This assay is a starting point for more sophisticated in vitro models of nutrition and disease resistance in honey bee larvae.

  20. PubMed Central

    Koumaré, B.; Achtman, M.; Bougoudogo, F.; Cisse, M.; Wang, J. F.

    1996-01-01

    The study deals with 570 strains of Neisseriaceae isolated between 1989 and 1994 in Mali: 396 of the strains were isolated from samples of cerebrospinal fluid and 174 from the throat. Serogroup C accounted for 55% of all strains. Antigenic structure was determined by ELISA, SDS-PAGE and transfer to nitrocellulose membrane for immunoblotting with monoclonal antibodies produced at the Max Planck Institute for Molecular Genetics. For serogroup A, the class 1 protein types found were P1.7 for strains isolated prior to 1994 and P1.9 for strains isolated in 1994. P1.7 is specific to clone IV-1 and P1.9 to clone III-1, which was responsible for the 1994 epidemic. All strains of serogroup C isolated from fluid CSF and most strains isolated from the throat exhibit a new type of class 1 protein which the authors have designated P1.y. P1.y is characteristic of Malian strains of serogroup C; it is rare or absent in strains from other countries (Burkina Faso, Ghana, Italy, USA). The nucleotide sequence of the gene expressing P1.y and the corresponding amino acid sequence were determined at the National Institute for Biological Standards and Control, England. Images Fig. 1 PMID:8925555

  1. Transport genes and chemotaxis in Laribacter hongkongensis: a genome-wide analysis

    PubMed Central

    2011-01-01

    Background Laribacter hongkongensis is a Gram-negative, sea gull-shaped rod associated with community-acquired gastroenteritis. The bacterium has been found in diverse freshwater environments including fish, frogs and drinking water reservoirs. Using the complete genome sequence data of L. hongkongensis, we performed a comprehensive analysis of putative transport-related genes and genes related to chemotaxis, motility and quorum sensing, which may help the bacterium adapt to the changing environments and combat harmful substances. Results A genome-wide analysis using Transport Classification Database TCDB, similarity and keyword searches revealed the presence of a large diversity of transporters (n = 457) and genes related to chemotaxis (n = 52) and flagellar biosynthesis (n = 40) in the L. hongkongensis genome. The transporters included those from all seven major transporter categories, which may allow the uptake of essential nutrients or ions, and extrusion of metabolic end products and hazardous substances. L. hongkongensis is unique among closely related members of Neisseriaceae family in possessing higher number of proteins related to transport of ammonium, urea and dicarboxylate, which may reflect the importance of nitrogen and dicarboxylate metabolism in this assacharolytic bacterium. Structural modeling of two C4-dicarboxylate transporters showed that they possessed similar structures to the determined structures of other DctP-TRAP transporters, with one having an unusual disulfide bond. Diverse mechanisms for iron transport, including hemin transporters for iron acquisition from host proteins, were also identified. In addition to the chemotaxis and flagella-related genes, the L. hongkongensis genome also contained two copies of qseB/qseC homologues of the AI-3 quorum sensing system. Conclusions The large number of diverse transporters and genes involved in chemotaxis, motility and quorum sensing suggested that the bacterium may utilize a complex system to

  2. Structure and function of the PorB porin from disseminating Neisseria gonorrhoeae.

    PubMed

    Zeth, Kornelius; Kozjak-Pavlovic, Vera; Faulstich, Michaela; Fraunholz, Martin; Hurwitz, Robert; Kepp, Oliver; Rudel, Thomas

    2013-02-01

    The outer membrane of Gram-negative bacteria contains a large number of channel-forming proteins, porins, for the uptake of small nutrient molecules. Neisseria gonorrhoeae PorBIA (PorB of serotype A) are associated with disseminating diseases and mediate a rapid bacterial invasion into host cells in a phosphate-sensitive manner. To gain insights into this structure-function relationship we analysed PorBIA by X-ray crystallography in the presence of phosphate and ATP. The structure of PorBIA in the complex solved at a resolution of 3.3 Å (1 Å=0.1 nm) displays a surplus of positive charges inside the channel. ATP ligand-binding in the channel is co-ordinated by the positively charged residues of the channel interior. These residues ligate the aromatic, sugar and pyrophosphate moieties of the ligand. Two phosphate ions were observed in the structure, one of which clamped by two arginine residues (Arg92 and Arg124) localized at the extraplasmic channel exit. A short β-bulge in β2-strand together with the long L3 loop narrow the barrel diameter significantly and further support substrate specificity through hydrogen bond interactions. Interestingly the structure also comprised a small peptide as a remnant of a periplasmic protein which physically links porin molecules to the peptidoglycan network. To test the importance of Arg92 on bacterial invasion the residue was mutated. In vivo assays of bacteria carrying a R92S mutation confirmed the importance of this residue for host-cell invasion. Furthermore systematic sequence and structure comparisons of PorBIA from Neisseriaceae indicated Arg92 to be unique in disseminating N. gonorrhoeae thereby possibly distinguishing invasion-promoting porins from other neisserial porins.

  3. Uruburuella testudinis sp. nov., isolated from tortoise (Testudo).

    PubMed

    Kuhnert, Peter; Thomann, Andreas; Brodard, Isabelle; Haefeli, Willi; Korczak, Bożena M

    2015-04-01

    A polyphasic taxonomic analysis was carried out on 11 uncommon Gram-stain-negative, non-motile, catalase- and oxidase-positive, but indole-negative, bacterial strains isolated from tortoises. Phenotypically and genetically they represented a homogeneous group of organisms most closely related to, but distinct from, Uruburuella suis. In a reconstructed 16S rRNA gene tree they clustered on a monophyletic branch next to U. suis with gene similarities between strains of 99.5-100%, and of up to 98.2% with U. suis . DNA-DNA hybridization indicated the organisms represented a novel species with only 40% DNA-DNA similarity with U. suis . Partial sequencing of rpoB resulted in two subclusters confirming the 16S rRNA gene phylogeny; both genes allowed clear separation and identification of the novel species. Furthermore, they could be unambiguously identified by matrix-assisted laser desorption ionization time-of-flight MS, where, again, they formed a highly homogeneous cluster separate from U. suis and other members of the family Neisseriaceae . The major fatty acids were C(16 : 0) and summed feature C(16 : 1)ω7c/iso-C(15 : 0) 2-OH. The DNA G+C content was 54.4 mol%. Based on phenotypic and genetic data we propose classifying these organisms as representatives of a novel species named Uruburuella testudinis sp. nov. The type strain is 07_OD624(T) ( = DSM 26510(T) = CCUG 63373(T)).

  4. Natural Competence and the Evolution of DNA Uptake Specificity

    PubMed Central

    Mell, Joshua Chang

    2014-01-01

    Many bacteria are naturally competent, able to actively transport environmental DNA fragments across their cell envelope and into their cytoplasm. Because incoming DNA fragments can recombine with and replace homologous segments of the chromosome, competence provides cells with a potent mechanism of horizontal gene transfer as well as access to the nutrients in extracellular DNA. This review starts with an introductory overview of competence and continues with a detailed consideration of the DNA uptake specificity of competent proteobacteria in the Pasteurellaceae and Neisseriaceae. Species in these distantly related families exhibit strong preferences for genomic DNA from close relatives, a self-specificity arising from the combined effects of biases in the uptake machinery and genomic overrepresentation of the sequences this machinery prefers. Other competent species tested lack obvious uptake bias or uptake sequences, suggesting that strong convergent evolutionary forces have acted on these two families. Recent results show that uptake sequences have multiple “dialects,” with clades within each family preferring distinct sequence variants and having corresponding variants enriched in their genomes. Although the genomic consensus uptake sequences are 12 and 29 to 34 bp, uptake assays have found that only central cores of 3 to 4 bp, conserved across dialects, are crucial for uptake. The other bases, which differ between dialects, make weaker individual contributions but have important cooperative interactions. Together, these results make predictions about the mechanism of DNA uptake across the outer membrane, supporting a model for the evolutionary accumulation and stability of uptake sequences and suggesting that uptake biases may be more widespread than currently thought. PMID:24488316

  5. Evaluation of Microbial Load in Oropharyngeal Mucosa from Tannery Workers

    PubMed Central

    Castellanos-Arévalo, Diana C.; Castellanos-Arévalo, Andrea P.; Camarena-Pozos, David A.; Colli-Mull, Juan G.; Maldonado-Vega, María

    2014-01-01

    Background Animal skin provides an ideal medium for the propagation of microorganisms and it is used like raw material in the tannery and footware industry. The aim of this study was to evaluate and identify the microbial load in oropharyngeal mucosa of tannery employees. Methods The health risk was estimated based on the identification of microorganisms found in the oropharyngeal mucosa samples. The study was conducted in a tanners group and a control group. Samples were taken from oropharyngeal mucosa and inoculated on plates with selective medium. In the samples, bacteria were identified by 16S ribosomal DNA analysis and the yeasts through a presumptive method. In addition, the sensitivity of these microorganisms to antibiotics/antifungals was evaluated. Results The identified bacteria belonged to the families Enterobacteriaceae, Pseudomonadaceae, Neisseriaceae, Alcaligenaceae, Moraxellaceae, and Xanthomonadaceae, of which some species are considered as pathogenic or opportunistic microorganisms; these bacteria were not present in the control group. Forty-two percent of bacteria identified in the tanners group are correlated with respiratory diseases. Yeasts were also identified, including the following species: Candida glabrata, Candida tropicalis, Candida albicans, and Candida krusei. Regarding the sensitivity test of bacteria identified in the tanners group, 90% showed sensitivity to piperacillin/tazobactam, 87% showed sensitivity to ticarcillin/clavulanic acid, 74% showed sensitivity to ampicillin/sulbactam, and 58% showed sensitivity to amoxicillin/clavulanic acid. Conclusion Several of the bacteria and yeast identified in the oropharyngeal mucosa of tanners have been correlated with infections in humans and have already been reported as airborne microorganisms in this working environment, representing a health risk for workers. PMID:25830072

  6. Genome sequence analyses show that Neisseria oralis is the same species as 'Neisseria mucosa var. heidelbergensis'.

    PubMed

    Bennett, Julia S; Jolley, Keith A; Maiden, Martin C J

    2013-10-01

    Phylogenies generated from whole genome sequence (WGS) data provide definitive means of bacterial isolate characterization for typing and taxonomy. The species status of strains recently defined with conventional taxonomic approaches as representing Neisseria oralis was examined by the analysis of sequences derived from WGS data, specifically: (i) 53 Neisseria ribosomal protein subunit (rps) genes (ribosomal multi-locus sequence typing, rMLST); and (ii) 246 Neisseria core genes (core genome MLST, cgMLST). These data were compared with phylogenies derived from 16S and 23S rRNA gene sequences, demonstrating that the N. oralis strains were monophyletic with strains described previously as representing 'Neisseria mucosa var. heidelbergensis' and that this group was of equivalent taxonomic status to other well-described species of the genus Neisseria. Phylogenetic analyses also indicated that Neisseria sicca and Neisseria macacae should be considered the same species as Neisseria mucosa and that Neisseria flavescens should be considered the same species as Neisseria subflava. Analyses using rMLST showed that some strains currently defined as belonging to the genus Neisseria were more closely related to species belonging to other genera within the family; however, whole genome analysis of a more comprehensive selection of strains from within the family Neisseriaceae would be necessary to confirm this. We suggest that strains previously identified as representing 'N. mucosa var. heidelbergensis' and deposited in culture collections should be renamed N. oralis. Finally, one of the strains of N. oralis was able to ferment lactose, due to the presence of β-galactosidase and lactose permease genes, a characteristic previously thought to be unique to Neisseria lactamica, which therefore cannot be thought of as diagnostic for this species; however, the rMLST and cgMLST analyses confirm that N. oralis is most closely related to N. mucosa.

  7. The Complete Genome and Proteome of Laribacter hongkongensis Reveal Potential Mechanisms for Adaptations to Different Temperatures and Habitats

    PubMed Central

    Curreem, Shirly O. T.; Tsang, Alan K. L.; Fan, Rachel Y. Y.; Wong, Gilman K. M.; Huang, Yi; Loman, Nicholas J.; Snyder, Lori A. S.; Cai, James J.; Huang, Jian-Dong; Mak, William; Pallen, Mark J.; Lok, Si; Yuen, Kwok-Yung

    2009-01-01

    Laribacter hongkongensis is a newly discovered Gram-negative bacillus of the Neisseriaceae family associated with freshwater fish–borne gastroenteritis and traveler's diarrhea. The complete genome sequence of L. hongkongensis HLHK9, recovered from an immunocompetent patient with severe gastroenteritis, consists of a 3,169-kb chromosome with G+C content of 62.35%. Genome analysis reveals different mechanisms potentially important for its adaptation to diverse habitats of human and freshwater fish intestines and freshwater environments. The gene contents support its phenotypic properties and suggest that amino acids and fatty acids can be used as carbon sources. The extensive variety of transporters, including multidrug efflux and heavy metal transporters as well as genes involved in chemotaxis, may enable L. hongkongensis to survive in different environmental niches. Genes encoding urease, bile salts efflux pump, adhesin, catalase, superoxide dismutase, and other putative virulence factors—such as hemolysins, RTX toxins, patatin-like proteins, phospholipase A1, and collagenases—are present. Proteomes of L. hongkongensis HLHK9 cultured at 37°C (human body temperature) and 20°C (freshwater habitat temperature) showed differential gene expression, including two homologous copies of argB, argB-20, and argB-37, which encode two isoenzymes of N-acetyl-L-glutamate kinase (NAGK)—NAGK-20 and NAGK-37—in the arginine biosynthesis pathway. NAGK-20 showed higher expression at 20°C, whereas NAGK-37 showed higher expression at 37°C. NAGK-20 also had a lower optimal temperature for enzymatic activities and was inhibited by arginine probably as negative-feedback control. Similar duplicated copies of argB are also observed in bacteria from hot springs such as Thermus thermophilus, Deinococcus geothermalis, Deinococcus radiodurans, and Roseiflexus castenholzii, suggesting that similar mechanisms for temperature adaptation may be employed by other bacteria. Genome and

  8. Effects of Early Intervention with Sodium Butyrate on Gut Microbiota and the Expression of Inflammatory Cytokines in Neonatal Piglets

    PubMed Central

    Xu, Jumei; Chen, Xue; Yu, Shuiqing; Su, Yong; Zhu, Weiyun

    2016-01-01

    Butyrate in the gut of animals has potential properties including regulating the innate immune, modulating the lipid metabolism, and protecting gut healthy. So far, only limited information on the impact of butyrate on the neonatal is available. This study aimed to investigate effects of oral administration of sodium butyrate (SB) on gut microbiota and the expression of inflammatory cytokine in neonatal piglets. Ten litters of crossbred newborn piglets were randomly allocated to the SB and control (CO) groups, each group consisted of five litters (replicates). Piglets in the SB group were orally administrated with 7 to 13 ml sodium butyrate solution (150 mmol/l) per day from the age of 1 to 7 days, respectively; piglets in the CO group were treated with the same dose of physiological saline. On days 8 and 21 (of age), gut digesta and tissues were collected for the analysis of microbiota, butyrate concentration and gene expression of inflammatory cytokine. Results showed that there was no difference in the butyrate concentration in the gut of piglets on days 8 and 21 between two groups. Real-time PCR assay showed that SB had no effect on the numbers of total bacteria in the stomach, ileum, and colon. MiSeq sequencing of the V3-V4 region of the 16S rRNA gene revealed that SB increased the richness in the stomach and colon, and the diversity of colonic microbiota on day 8 (P < 0.05). Genera Acinetobacter, Actinobacillus, Facklamia, Globicatella, Kocuria, Rothia, unclassified Leptotrichiaceae, unclassified Neisseriaceae, and unclassified Prevotellaceae in the stomach were increased in relative abundance by SB treatment, whereas the abundances of Lactobacillus decreased on day 8 (P < 0.05). At the genus and operational taxonomic unit (OTU) levels, SB had low impact on bacterial community in the ileum and colon on days 8 and 21. SB treatment decreased the expression of IL-6, IL-8, IFN-γ, IL-10, TGF-β, and histone deacetylase 1 (HDAC1) in the ileum of piglets on day 8

  9. Effects of Early Intervention with Sodium Butyrate on Gut Microbiota and the Expression of Inflammatory Cytokines in Neonatal Piglets.

    PubMed

    Xu, Jumei; Chen, Xue; Yu, Shuiqing; Su, Yong; Zhu, Weiyun

    2016-01-01

    Butyrate in the gut of animals has potential properties including regulating the innate immune, modulating the lipid metabolism, and protecting gut healthy. So far, only limited information on the impact of butyrate on the neonatal is available. This study aimed to investigate effects of oral administration of sodium butyrate (SB) on gut microbiota and the expression of inflammatory cytokine in neonatal piglets. Ten litters of crossbred newborn piglets were randomly allocated to the SB and control (CO) groups, each group consisted of five litters (replicates). Piglets in the SB group were orally administrated with 7 to 13 ml sodium butyrate solution (150 mmol/l) per day from the age of 1 to 7 days, respectively; piglets in the CO group were treated with the same dose of physiological saline. On days 8 and 21 (of age), gut digesta and tissues were collected for the analysis of microbiota, butyrate concentration and gene expression of inflammatory cytokine. Results showed that there was no difference in the butyrate concentration in the gut of piglets on days 8 and 21 between two groups. Real-time PCR assay showed that SB had no effect on the numbers of total bacteria in the stomach, ileum, and colon. MiSeq sequencing of the V3-V4 region of the 16S rRNA gene revealed that SB increased the richness in the stomach and colon, and the diversity of colonic microbiota on day 8 (P < 0.05). Genera Acinetobacter, Actinobacillus, Facklamia, Globicatella, Kocuria, Rothia, unclassified Leptotrichiaceae, unclassified Neisseriaceae, and unclassified Prevotellaceae in the stomach were increased in relative abundance by SB treatment, whereas the abundances of Lactobacillus decreased on day 8 (P < 0.05). At the genus and operational taxonomic unit (OTU) levels, SB had low impact on bacterial community in the ileum and colon on days 8 and 21. SB treatment decreased the expression of IL-6, IL-8, IFN-γ, IL-10, TGF-β, and histone deacetylase 1 (HDAC1) in the ileum of piglets on day 8