These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

Global and phylogenetic distribution of quorum sensing signals, acyl homoserine lactones, in the family of vibrionaceae.  

PubMed

Bacterial quorum sensing (QS) and the corresponding signals, acyl homoserine lactones (AHLs), were first described for a luminescent Vibrio species. Since then, detailed knowledge has been gained on the functional level of QS; however, the abundance of AHLs in the family of Vibrionaceae in the environment has remained unclear. Three hundred and one Vibrionaceae strains were collected on a global research cruise and the prevalence and profile of AHL signals in this global collection were determined. AHLs were detected in 32 of the 301 strains using Agrobacterium tumefaciens and Chromobacterium violaceum reporter strains. Ethyl acetate extracts of the cultures were analysed by ultra-high performance liquid chromatography-high resolution mass spectrometry (MS) with automated tandem MS confirmation for AHLs. N-(3-hydroxy-hexanoyl) (OH-C6) and N-(3-hydroxy-decanoyl) (OH-C10) homoserine lactones were the most common AHLs found in 17 and 12 strains, respectively. Several strains produced a diversity of different AHLs, including N-heptanoyl (C7) HL. AHL-producing Vibrionaceae were found in polar, temperate and tropical waters. The AHL profiles correlated with strain phylogeny based on gene sequence homology, however not with geographical location. In conclusion, a wide range of AHL signals are produced by a number of clades in the Vibrionaceae family and these results will allow future investigations of inter- and intra-species interactions within this cosmopolitan family of marine bacteria. PMID:25419995

Rasmussen, Bastian Barker; Nielsen, Kristian Fog; Machado, Henrique; Melchiorsen, Jette; Gram, Lone; Sonnenschein, Eva C

2014-11-01

2

Global and Phylogenetic Distribution of Quorum Sensing Signals, Acyl Homoserine Lactones, in the Family of Vibrionaceae  

PubMed Central

Bacterial quorum sensing (QS) and the corresponding signals, acyl homoserine lactones (AHLs), were first described for a luminescent Vibrio species. Since then, detailed knowledge has been gained on the functional level of QS; however, the abundance of AHLs in the family of Vibrionaceae in the environment has remained unclear. Three hundred and one Vibrionaceae strains were collected on a global research cruise and the prevalence and profile of AHL signals in this global collection were determined. AHLs were detected in 32 of the 301 strains using Agrobacterium tumefaciens and Chromobacterium violaceum reporter strains. Ethyl acetate extracts of the cultures were analysed by ultra-high performance liquid chromatography-high resolution mass spectrometry (MS) with automated tandem MS confirmation for AHLs. N-(3-hydroxy-hexanoyl) (OH-C6) and N-(3-hydroxy-decanoyl) (OH-C10) homoserine lactones were the most common AHLs found in 17 and 12 strains, respectively. Several strains produced a diversity of different AHLs, including N-heptanoyl (C7) HL. AHL-producing Vibrionaceae were found in polar, temperate and tropical waters. The AHL profiles correlated with strain phylogeny based on gene sequence homology, however not with geographical location. In conclusion, a wide range of AHL signals are produced by a number of clades in the Vibrionaceae family and these results will allow future investigations of inter- and intra-species interactions within this cosmopolitan family of marine bacteria. PMID:25419995

Barker Rasmussen, Bastian; Fog Nielsen, Kristian; Machado, Henrique; Melchiorsen, Jette; Gram, Lone; Sonnenschein, Eva C.

2014-01-01

3

Presence of acyl-homoserine lactones in 57 members of the Vibrionaceae family  

PubMed Central

Aims?The aim of this study was to use a sensitive method to screen and quantify 57 Vibrionaceae strains for the production of acyl-homoserine lactones (AHLs) and map the resulting AHL profiles onto a host phylogeny. Methods and Results?We used a high-performance liquid chromatography–tandem mass spectrometry (HPLC-MS/MS) protocol to measure AHLs in spent media after bacterial growth. First, the presence/absence of AHLs (qualitative analysis) was measured to choose internal standard for subsequent quantitative AHL measurements. We screened 57 strains from three genera (Aliivibrio,Photobacterium and Vibrio) of the same family (i.e. Vibrionaceae). Our results show that about half of the isolates produced multiple AHLs, typically at 25–5000?nmol?l?1. Conclusions?This work shows that production of AHL quorum sensing signals is found widespread among Vibrionaceae bacteria and that closely related strains typically produce similar AHL profiles. Significance and Impact of the Study?The AHL detection protocol presented in this study can be applied to a broad range of bacterial samples and may contribute to a wider mapping of AHL production in bacteria, for example, in clinically relevant strains. PMID:23725044

Purohit, AA; Johansen, J?A; Hansen, H; Leiros, H-KS; Kashulin, A; Karlsen, C; Smalås, A; Haugen, P; Willassen, NP

2013-01-01

4

Development of a Simple and Rapid Fluorogenic Procedure for Identification of Vibrionaceae Family Members  

PubMed Central

We describe a simple colony overlay procedure for peptidases (COPP) for the rapid fluorogenic detection and quantification of Vibrionaceae from seawater, shellfish, sewage, and clinical samples. The assay detects phosphoglucose isomerase with a lysyl aminopeptidase activity that is produced by Vibrionaceae family members. Overnight cultures are overlaid for 10 min with membranes containing a synthetic substrate, and the membranes are examined for fluorescent foci under UV illumination. Fluorescent foci were produced by all the Vibrionaceae tested, including Vibrio spp., Aeromonas spp., and Plesiomonas spp. Fluorescence was not produced by non-Vibrionaceae pathogens. Vibrio cholerae strains O1, O139, O22, and O155 were strongly positive. Seawater and oysters were assayed, and 87 of 93 (93.5%) of the positive isolates were identified biochemically as Vibrionaceae, principally Vibrio vulnificus, Vibrio parahaemolyticus, Aeromonas hydrophila, Photobacterium damselae, and Shewanella putrefaciens. None of 50 nonfluorescent isolates were Vibrionaceae. No Vibrionaceae were detected in soil, and only A. hydrophila was detected in sewage. The COPP technique may be particularly valuable in environmental and food-testing laboratories and for monitoring water quality in the aquaculture industry. PMID:16000757

Richards, Gary P.; Watson, Michael A.; Parveen, Salina

2005-01-01

5

Genomic and systems evolution in Vibrionaceae species  

PubMed Central

Background The steadily increasing number of prokaryotic genomes has accelerated the study of genome evolution; in particular, the availability of sets of genomes from closely related bacteria has facilitated the exploration of the mechanisms underlying genome plasticity. The family Vibrionaceae is found in the Gammaproteobacteria and is abundant in aquatic environments. Taxa from the family Vibrionaceae are diversified in their life styles; some species are free living, others are symbiotic, and others are human pathogens. This diversity makes this family a useful set of model organisms for studying bacterial evolution. This evolution is driven by several forces, among them gene duplication and lateral gene transfer, which are believed to provide raw material for functional redundancy and novelty. The resultant gene copy increase in one genome is then detected as lineage-specific expansion (LSE). Results Here we present the results of a detailed comparison of the genomes of eleven Vibrionaceae strains that have distinct life styles and distinct phenotypes. The core genome shared by all eleven strains is composed of 1,882 genes, which make up about 31%–50% of the genome repertoire. We further investigated the distribution and features of genes that have been specifically expanded in one unique lineage of the eleven strains. Abundant duplicate genes have been identified in the eleven Vibrionaceae strains, with 1–11% of the whole genomes composed lineage specific radiations. These LSEs occurred in two distinct patterns: the first type yields one or more copies of a single gene; we call this a single gene expansion. The second pattern has a high evolutionary impact, as the expansion involves two or more gene copies in a block, with the duplicated block located next to the original block (a contiguous block expansion) or at some distance from the original block (a discontiguous block expansion). We showed that LSEs involve genes that are tied to defense and pathogenesis mechanisms as well as in the fundamental life cycle of Vibrionaceae species. Conclusion Our results provide evidence of genome plasticity and rapid evolution within the family Vibrionaceae. The comparisons point to sources of genomic variation and candidates for lineage-specific adaptations of each Vibrionaceae pathogen or nonpathogen strain. Such lineage specific expansions could reveal components in bacterial systems that, by their enhanced genetic variability, can be tied to responses to environmental challenges, interesting phenotypes, or adaptive pathogenic responses to host challenges. PMID:19594870

Gu, Jianying; Neary, Jennifer; Cai, Hong; Moshfeghian, Audrey; Rodriguez, Stephen A; Lilburn, Timothy G; Wang, Yufeng

2009-01-01

6

Phylogenetic relationships of marine bacteria, mainly members of the family Vibrionaceae, determined on the basis of 16S rRNA sequences.  

PubMed

The phylogenetic relationships of 50 reference strains, mostly marine bacteria which require Na+ for growth, were determined on the basis of 600 16S rRNA nucleotides by using reverse transcriptase sequencing. Strains belonging to 10 genera were included (four genera of the family Vibrionaceae, the genus Aeromonas of the family Aeromonadaceae, and the genera Alteromonas, Marinomonas, Shewanella, Pseudomonas, and Deleya). The sequences were aligned, the similarity values and evolutionary distance values were determined, and a phylogenetic tree was constructed by using the neighbor-joining method. On the basis of our results, the family Vibrionaceae was separated into at least seven groups (genera and families). Vibrio marinus clearly was on a line of descent that was remote from other vibrios. As determined by the similarity and evolutionary distance values, V. marinus is more distantly related to the family Vibrionaceae than the members of the Aeromonadaceae are. Also, Vibrio cholerae strains formed a separate group with Vibrio mimicus at the genus level. Of 30 species of the Vibrionaceae, 17 formed a large phylogenetic cluster. The genus Listonella was found to be a heterogeneous group, and the species were distributed in various subgroups of the Vibrionaceae. The separation of the family Aeromonadaceae from the family Vibrionaceae and the separation of the genera Marinomonas and Shewanella from the genus Alteromonas were confirmed in this phylogenetic study. However, a marine Pseudomonas species, Pseudomonas nautica, was clearly separated from two terrestrial Pseudomonas species. Each group that was separated by the phylogenetic analysis had characteristic 16S rRNA sequence patterns that were common only to species in that group. Therefore, the characteristic sequences described in this paper may be useful for identification purposes. PMID:8427811

Kita-Tsukamoto, K; Oyaizu, H; Nanba, K; Simidu, U

1993-01-01

7

Genomic and systems evolution in Vibrionaceae species  

Microsoft Academic Search

BACKGROUND: The steadily increasing number of prokaryotic genomes has accelerated the study of genome evolution; in particular, the availability of sets of genomes from closely related bacteria has facilitated the exploration of the mechanisms underlying genome plasticity. The family Vibrionaceae is found in the Gammaproteobacteria and is abundant in aquatic environments. Taxa from the family Vibrionaceae are diversified in their

Jianying Gu; Jennifer Neary; Hong Cai; Audrey Moshfeghian; Stephen A Rodriguez; Timothy G Lilburn; Yufeng Wang

2009-01-01

8

Water quality parameters and total aerobic bacterial and vibrionaceae loads in eastern oysters (Crassostrea virginica) from oyster gardening sites  

Technology Transfer Automated Retrieval System (TEKTRAN)

Oyster gardening is a practice designed to restore habitat for marine life and to improve water quality. This study determined physical and chemical water quality parameters at two oyster gardening sites in the Delaware Inland Bays and compared them with total aerobic bacteria and Vibrionaceae conc...

9

Antibacterial compounds from marine Vibrionaceae isolated on a global expedition.  

PubMed

On a global research expedition, over 500 bacterial strains inhibitory towards pathogenic bacteria were isolated. Three hundred of the antibacterial strains were assigned to the Vibrionaceae family. The purpose of the present study was to investigate the phylogeny and bioactivity of five Vibrionaceae strains with pronounced antibacterial activity. These were identified as Vibrio coralliilyticus (two strains), V. neptunius (two strains), and Photobacterium halotolerans (one strain) on the basis of housekeeping gene sequences. The two related V. coralliilyticus and V. neptunius strains were isolated from distant oceanic regions. Chemotyping by LC-UV/MS underlined genetic relationships by showing highly similar metabolite profiles for each of the two V. coralliilyticus and V. neptunius strains, respectively, but a unique profile for P. halotolerans. Bioassay-guided fractionation identified two known antibiotics as being responsible for the antibacterial activity; andrimid (from V. coralliilyticus) and holomycin (from P. halotolerans). Despite the isolation of already known antibiotics, our findings show that marine Vibrionaceae are a resource of antibacterial compounds and may have potential for future natural product discovery. PMID:21339958

Wietz, Matthias; Mansson, Maria; Gotfredsen, Charlotte H; Larsen, Thomas O; Gram, Lone

2010-01-01

10

Antibacterial Compounds from Marine Vibrionaceae Isolated on a Global Expedition  

PubMed Central

On a global research expedition, over 500 bacterial strains inhibitory towards pathogenic bacteria were isolated. Three hundred of the antibacterial strains were assigned to the Vibrionaceae family. The purpose of the present study was to investigate the phylogeny and bioactivity of five Vibrionaceae strains with pronounced antibacterial activity. These were identified as Vibrio coralliilyticus (two strains), V. neptunius (two strains), and Photobacterium halotolerans (one strain) on the basis of housekeeping gene sequences. The two related V. coralliilyticus and V. neptunius strains were isolated from distant oceanic regions. Chemotyping by LC-UV/MS underlined genetic relationships by showing highly similar metabolite profiles for each of the two V. coralliilyticus and V. neptunius strains, respectively, but a unique profile for P. halotolerans. Bioassay-guided fractionation identified two known antibiotics as being responsible for the antibacterial activity; andrimid (from V. coralliilyticus) and holomycin (from P. halotolerans). Despite the isolation of already known antibiotics, our findings show that marine Vibrionaceae are a resource of antibacterial compounds and may have potential for future natural product discovery. PMID:21339958

Wietz, Matthias; Mansson, Maria; Gotfredsen, Charlotte H.; Larsen, Thomas O.; Gram, Lone

2010-01-01

11

Fluorogenic Membrane Overlays to Enumerate Total and Fecal Escherichia coli and Total Vibrionaceae in Shellfish and Seawater  

PubMed Central

Three assays were developed to enumerate total and fecal Escherichia coli and total Vibrionaceae in shellfish, seawater, and other foods and environmental samples. Assays involve membrane overlays of overnight colonies on nonselective agar plates to detect ?-glucuronidase and lysyl aminopeptidase activities for E. coli and Vibrionaceae, respectively. Cellulose membranes containing the substrates 4-methylumbeferyl-?-D-glucuronide (MUG) produced a bright blue fluorescence when overlaid onto E. coli, while L-lysyl-7-amino-4-trifluoromethylcoumarin produced green fluorescent foci when overlaid onto Vibrionaceae family members. A multiplex assay was also developed for simultaneously enumerating total E. coli and total Vibrionaceae in oysters and seawater. Overall, 65% of overlaid E. coli (non-O157:H7) were MUG-positive, compared with 62% as determined by the most-probable-number-MUG assay. The overlays are rapid, simple, and cost effective for quantification purposes. This research provides practical alternatives for monitoring bacterial indicators and potential pathogens in complex samples, including molluscan shellfish. PMID:20396663

Richards, Gary P.; Watson, Michael A.

2010-01-01

12

Fluorogenic Membrane Overlays to Enumerate Total and Fecal Escherichia coli and Total Vibrionaceae in Shellfish and Seawater.  

PubMed

Three assays were developed to enumerate total and fecal Escherichia coli and total Vibrionaceae in shellfish, seawater, and other foods and environmental samples. Assays involve membrane overlays of overnight colonies on nonselective agar plates to detect beta-glucuronidase and lysyl aminopeptidase activities for E. coli and Vibrionaceae, respectively. Cellulose membranes containing the substrates 4-methylumbeferyl-beta-D-glucuronide (MUG) produced a bright blue fluorescence when overlaid onto E. coli, while L-lysyl-7-amino-4-trifluoromethylcoumarin produced green fluorescent foci when overlaid onto Vibrionaceae family members. A multiplex assay was also developed for simultaneously enumerating total E. coli and total Vibrionaceae in oysters and seawater. Overall, 65% of overlaid E. coli (non-O157:H7) were MUG-positive, compared with 62% as determined by the most-probable-number-MUG assay. The overlays are rapid, simple, and cost effective for quantification purposes. This research provides practical alternatives for monitoring bacterial indicators and potential pathogens in complex samples, including molluscan shellfish. PMID:20396663

Richards, Gary P; Watson, Michael A

2010-01-01

13

Small RNAs in the Vibrionaceae: an ocean still to be explored.  

PubMed

In bacteria, the discovery of noncoding small RNAs (sRNAs) as modulators of gene expression in response to environmental signals has brought new insights into bacterial gene regulation, including control of pathogenicity. The Vibrionaceae constitute a family of marine bacteria of which many are responsible for infections affecting not only humans, such as Vibrio cholerae but also fish and marine invertebrates, representing the major cause of mortality in farmed marine species. They are able to colonize many habitats, existing as planktonic forms, in biofilms or associated with various hosts. This high adaptability is linked to their capacity to generate genetic diversity, in part through lateral gene transfer, but also by varying gene expression control. In the recent years, several major studies have illustrated the importance of small regulatory sRNAs in the Vibrionaceae for the control of pathogenicity and adaptation to environment and nutrient sources such as chitin, especially in V. cholerae and Vibrio harveyi. The existence of a complex regulatory network controlled by quorum sensing has been demonstrated in which sRNAs play central roles. This review covers major advances made in the discovery and elucidation of functions of Vibrionaceae sRNAs within the last 10?years. PMID:24458378

Nguyen, An Ngoc; Jacq, Annick

2014-01-01

14

Water-quality parameters and total aerobic bacterial and Vibrionaceae loads in Eastern oysters (Crassostrea virginica) from oyster-gardening sites.  

PubMed

Oyster gardening is a practice designed to restore habitat for marine life and to improve water quality. This study determined physical and chemical water-quality parameters at two oyster gardening sites in the Delaware Inland Bays and compared them with total aerobic bacteria and Vibrionaceae concentrations in Eastern oysters (Crassostrea virginica). One site was located at the end of a man-made canal, whereas the other was located in an open bay. Measured water parameters included temperature, dissolved oxygen (DO), salinity, pH, total nitrogen, nitrate, nitrite, total phosphorus, and total suspended solids. The highest Vibrionaceae levels, as determined by the colony overlay procedure for peptidases, were at the canal site in September (3.5 × 10(5) g(-1)) and at the bay site in August (1.9 × 10(5) g(-1)). Vibrionaceae levels were significantly greater during the duration of the study at the canal site (P = 0.01). This study provides the first baseline levels for total Vibrionaceae in the Delaware Inland Bays. Minimum DO readings at the bay and canal sites were 3.0 and 2.3 mg l(-1), respectively, far less than the state-targeted minimum threshold of 5.0 mg l(-1). Total phosphorus levels exceeded recommendations of ?0.1 mg l(-1) at the bay and canal sites for all monthly samplings, with mean monthly highs at both sites ?0.68 mg l(-1) in August. Nitrogen occasionally exceeded the recommended level of 1.0 mg l(-1) at both sites. Overall, waters were highly degraded from high phosphates, nitrogen, and total suspended solids as well as low DO. PMID:22183874

Fay, Johnna P; Richards, Gary P; Ozbay, Gulnihal

2012-05-01

15

Associations and dynamics of Vibrionaceae in the environment, from the genus to the population level  

E-print Network

The Vibrionaceae, which encompasses several potential pathogens, including V. cholerae, the causative agent of cholera, and V. vulnificus, the deadliest seafood-borne pathogen, are a well-studied family of marine bacteria ...

Chien, Diana M.

16

Production of Bioactive Secondary Metabolites by Marine Vibrionaceae  

PubMed Central

Bacteria belonging to the Vibrionaceae family are widespread in the marine environment. Today, 128 species of vibrios are known. Several of them are infamous for their pathogenicity or symbiotic relationships. Despite their ability to interact with eukaryotes, the vibrios are greatly underexplored for their ability to produce bioactive secondary metabolites and studies have been limited to only a few species. Most of the compounds isolated from vibrios so far are non-ribosomal peptides or hybrids thereof, with examples of N-containing compounds produced independent of nonribosomal peptide synthetases (NRPS). Though covering a limited chemical space, vibrios produce compounds with attractive biological activities, including antibacterial, anticancer, and antivirulence activities. This review highlights some of the most interesting structures from this group of bacteria. Many compounds found in vibrios have also been isolated from other distantly related bacteria. This cosmopolitan occurrence of metabolites indicates a high incidence of horizontal gene transfer, which raises interesting questions concerning the ecological function of some of these molecules. This account underlines the pending potential for exploring new bacterial sources of bioactive compounds and the challenges related to their investigation. PMID:22131950

Mansson, Maria; Gram, Lone; Larsen, Thomas O.

2011-01-01

17

Phylogenetic Analysis of the Incidence of lux Gene Horizontal Transfer in Vibrionaceae  

Microsoft Academic Search

Received 21 January 2008\\/Accepted 11 March 2008 Horizontal gene transfer (HGT) is thought to occur frequently in bacteria in nature and to play an important role in bacterial evolution, contributing to the formation of new species. To gain insight into the frequency of HGT in Vibrionaceae and its possible impact on speciation, we assessed the incidence of interspecies transfer of

Henryk Urbanczyk; Jennifer C. Ast; Allison J. Kaeding; James D. Oliver; Paul V. Dunlap

2008-01-01

18

The genomic code: inferring Vibrionaceae niche specialization.  

PubMed

The Vibrionaceae show a wide range of niche specialization, from free-living forms to those attached to biotic and abiotic surfaces, from symbionts to pathogens and from estuarine inhabitants to deep-sea piezophiles. The existence of complete genome sequences for closely related species from varied aquatic niches makes this group an excellent case study for genome comparison. PMID:16894340

Reen, F Jerry; Almagro-Moreno, Salvador; Ussery, David; Boyd, E Fidelma

2006-09-01

19

Microbial experimental evolution as a novel research approach in the Vibrionaceae and squid-Vibrio symbiosis  

PubMed Central

The Vibrionaceae are a genetically and metabolically diverse family living in aquatic habitats with a great propensity toward developing interactions with eukaryotic microbial and multicellular hosts (as either commensals, pathogens, and mutualists). The Vibrionaceae frequently possess a life history cycle where bacteria are attached to a host in one phase and then another where they are free from their host as either part of the bacterioplankton or adhered to solid substrates such as marine sediment, riverbeds, lakebeds, or floating particulate debris. These two stages in their life history exert quite distinct and separate selection pressures. When bound to solid substrates or to host cells, the Vibrionaceae can also exist as complex biofilms. The association between bioluminescent Vibrio spp. and sepiolid squids (Cephalopoda: Sepiolidae) is an experimentally tractable model to study bacteria and animal host interactions, since the symbionts and squid hosts can be maintained in the laboratory independently of one another. The bacteria can be grown in pure culture and the squid hosts raised gnotobiotically with sterile light organs. The partnership between free-living Vibrio symbionts and axenic squid hatchlings emerging from eggs must be renewed every generation of the cephalopod host. Thus, symbiotic bacteria and animal host can each be studied alone and together in union. Despite virtues provided by the Vibrionaceae and sepiolid squid-Vibrio symbiosis, these assets to evolutionary biology have yet to be fully utilized for microbial experimental evolution. Experimental evolution studies already completed are reviewed, along with exploratory topics for future study. PMID:25538686

Soto, William; Nishiguchi, Michele K.

2014-01-01

20

A new family of bacterial condensins  

PubMed Central

Condensins play a central role in global chromatin organization. In bacteria, two families of condensins have been identified, the MukBEF and SMC-ScpAB complexes. Only one of the two complexes is usually found in a given species, giving rise to a paradigm that a single condensin organizes bacterial chromosomes. Using sequence analysis, we identified a third family of condensins, MksBEF (MukBEF-like SMC proteins), which is broadly present in diverse bacteria. The proteins appear distantly related to MukBEF, have a similar operon organization and similar predicted secondary structures albeit with notably shorter coiled coils. All three subunits of MksBEF exhibit significant sequence variation and can be divided into a series of overlapping subfamilies. MksBEF often coexists with the SMC-ScpAB, MukBEF and, sometimes, other MksBEFs. In Pseudomonas aeruginosa, both SMC and MksB contribute to faithful chromosome partitioning, with their inactivation leading to increased frequencies of anucleate cells. Moreover, MksBEF can complement anucleate cell formation in SMC-deficient cells. Purified PaMksB showed activities typical for condensins including ATP-modulated DNA binding and condensation. Notably, DNA binding by MksB is negatively regulated by ATP, which sets it apart from other known SMC proteins. Thus, several specialized condensins might be involved in organization of bacterial chromosomes. PMID:21752107

Petrushenko, Zoya M.; She, Weifeng; Rybenkov, Valentin V.

2011-01-01

21

The fur gene as a new phylogenetic marker for vibrionaceae species identification.  

PubMed

Microbial taxonomy is essential in all areas of microbial science. The 16S rRNA gene sequence is one of the main phylogenetic species markers; however, it does not provide discrimination in the family Vibrionaceae, where other molecular techniques allow better interspecies resolution. Although multilocus sequence analysis (MLSA) has been used successfully in the identification of Vibrio species, the technique has several limitations. They include the fact that several locus amplifications and sequencing have to be performed, which still sometimes lead to doubtful identifications. Using an in silico approach based on genomes from 103 Vibrionaceae strains, we demonstrate here the high resolution of the fur gene in the identification of Vibrionaceae species and its usefulness as a phylogenetic marker. The fur gene showed within-species similarity higher than 95%, and the relationships inferred from its use were in agreement with those observed for 16S rRNA analysis and MLSA. Furthermore, we developed a fur PCR sequencing-based method that allowed identification of Vibrio species. The discovery of the phylogenetic power of the fur gene and the development of a PCR method that can be used in amplification and sequencing of the gene are of general interest whether for use alone or together with the previously suggested loci in an MLSA. PMID:25662978

Machado, Henrique; Gram, Lone

2015-04-15

22

Genomic and Metabolic Profiling of Nonulosonic Acids in Vibrionaceae Reveal Biochemical Phenotypes of Allelic Divergence in Vibrio vulnificus ?  

PubMed Central

Nonulosonic acids (NulOs) encompass a large group of structurally diverse nine-carbon backbone ?-keto sugars widely distributed among the three domains of life. Mammals express a specialized version of NulOs called sialic acids, which are displayed in prominent terminal positions of cell surface and secreted glycoconjugates. Within bacteria, the ability to synthesize NulOs has been demonstrated in a number of human pathogens and is phylogenetically widespread. Here we examine the distribution, diversity, evolution, and function of NulO biosynthesis pathways in members of the family Vibrionaceae. Among 27 species of Vibrionaceae examined at the genomic level, 12 species contained nab gene clusters. We document examples of duplication, divergence, horizontal transfer, and recombination of nab gene clusters in different Vibrionaceae lineages. Biochemical analyses, including mass spectrometry, confirmed that many species do, in fact, produce di-N-acetylated NulOs. A library of clinical and environmental isolates of Vibrio vulnificus served as a model for further investigation of nab allele genotypes and levels of NulO expression. The data show that lineage I isolates produce about 20-fold higher levels of NulOs than lineage II isolates. Moreover, nab gene alleles found in a subset of V. vulnificus clinical isolates express 40-fold higher levels of NulOs than nab alleles associated with environmental isolates. Taken together, the data implicate the family Vibrionaceae as a “hot spot” of NulO evolution and suggest that these molecules may have diverse roles in environmental persistence and/or animal virulence. PMID:21724895

Lewis, Amanda L.; Lubin, Jean-Bernard; Argade, Shilpa; Naidu, Natasha; Choudhury, Biswa; Boyd, E. Fidelma

2011-01-01

23

Conservation of the Chitin Utilization Pathway in the Vibrionaceae? †  

PubMed Central

Vibrionaceae are regarded as important marine chitin degraders, and attachment to chitin regulates important biological functions; yet, the degree of chitin pathway conservation in Vibrionaceae is unknown. Here, a core chitin degradation pathway is proposed based on comparison of 19 Vibrio and Photobacterium genomes with a detailed metabolic map assembled for V. cholerae from published biochemical, genomic, and transcriptomic results. Further, to assess whether chitin degradation is a conserved property of Vibrionaceae, a set of 54 strains from 32 taxa were tested for the ability to grow on various forms of chitin. All strains grew on N-acetylglucosamine (GlcNAc), the monomer of chitin. The majority of isolates grew on ? (crab shell) and ? (squid pen) chitin and contained chitinase A (chiA) genes. chiA sequencing and phylogenetic analysis suggest that this gene is a good indicator of chitin metabolism but appears subject to horizontal gene transfer and duplication. Overall, chitin metabolism appears to be a core function of Vibrionaceae, but individual pathway components exhibit dynamic evolutionary histories. PMID:17933912

Hunt, Dana E.; Gevers, Dirk; Vahora, Nisha M.; Polz, Martin F.

2008-01-01

24

Characterization of the Bacterial Diversity in Indo-West Pacific Loliginid and Sepiolid Squid Light Organs  

PubMed Central

Loliginid and sepiolid squid light organs are known to host a variety of bacterial species from the family Vibrionaceae, yet little is known about the species diversity and characteristics among different host squids. Here we present a broad-ranging molecular and physiological analysis of the bacteria colonizing light organs in loliginid and sepiolid squids from various field locations of the Indo-West Pacific (Australia and Thailand). Our PCR-RFLP analysis, physiological characterization, carbon utilization profiling, and electron microscopy data indicate that loliginid squid in the Indo-West Pacific carry a consortium of bacterial species from the families Vibrionaceae and Photobacteriaceae. This research also confirms our previous report of the presence of Vibrio harveyi as a member of the bacterial population colonizing light organs in loliginid squid. pyrH sequence data were used to confirm isolate identity, and indicates that Vibrio and Photobacterium comprise most of the light organ colonizers of squids from Australia, confirming previous reports for Australian loliginid and sepiolid squids. In addition, combined phylogenetic analysis of PCR-RFLP and 16S rDNA data from Australian and Thai isolates associated both Photobacterium and Vibrio clades with both loliginid and sepiolid strains, providing support that geographical origin does not correlate with their relatedness. These results indicate that both loliginid and sepiolid squids demonstrate symbiont specificity (Vibrionaceae), but their distribution is more likely due to environmental factors that are present during the infection process. This study adds significantly to the growing evidence for complex and dynamic associations in nature and highlights the importance of exploring symbiotic relationships in which non-virulent strains of pathogenic Vibrio species could establish associations with marine invertebrates. PMID:22885637

Guerrero-Ferreira, Ricardo; Gorman, Clayton; Chavez, Alba A.; Willie, Shantell

2013-01-01

25

Jellyfish Modulate Bacterial Dynamic and Community Structure  

PubMed Central

Jellyfish blooms have increased in coastal areas around the world and the outbreaks have become longer and more frequent over the past few decades. The Mediterranean Sea is among the heavily affected regions and the common bloom - forming taxa are scyphozoans Aurelia aurita s.l., Pelagia noctiluca, and Rhizostoma pulmo. Jellyfish have few natural predators, therefore their carcasses at the termination of a bloom represent an organic-rich substrate that supports rapid bacterial growth, and may have a large impact on the surrounding environment. The focus of this study was to explore whether jellyfish substrate have an impact on bacterial community phylotype selection. We conducted in situ jellyfish - enrichment experiment with three different jellyfish species. Bacterial dynamic together with nutrients were monitored to assess decaying jellyfish-bacteria dynamics. Our results show that jellyfish biomass is characterized by protein rich organic matter, which is highly bioavailable to ‘jellyfish - associated’ and ‘free - living’ bacteria, and triggers rapid shifts in bacterial population dynamics and composition. Based on 16S rRNA clone libraries and denaturing gradient gel electrophoresis (DGGE) analysis, we observed a rapid shift in community composition from unculturable Alphaproteobacteria to culturable species of Gammaproteobacteria and Flavobacteria. The results of sequence analyses of bacterial isolates and of total bacterial community determined by culture independent genetic analysis showed the dominance of the Pseudoalteromonadaceae and the Vibrionaceae families. Elevated levels of dissolved proteins, dissolved organic and inorganic nutrient release, bacterial abundance and carbon production as well as ammonium concentrations characterized the degradation process. The biochemical composition of jellyfish species may influence changes in the amount of accumulated dissolved organic and inorganic nutrients. Our results can contribute insights into possible changes in bacterial population dynamics and nutrient pathways following jellyfish blooms which have important implications for ecology of coastal waters. PMID:22745726

Tinta, Tinkara; Kogovšek, Tjaša; Malej, Alenka; Turk, Valentina

2012-01-01

26

BTLCP proteins: a novel family of bacterial transglutaminase-like cysteine proteinases  

Microsoft Academic Search

Using sequence similarity searches and top-of-the-range fold-recognition methods, we have identified a novel family of bacterial transglutaminase-like cysteine proteinases (BTLCPs) with an invariant Cys-His-Asp catalytic triad and a predicted N-terminal signal sequence. This family of previously uncharacterized hypothetical proteins encompasses sequences of unknown function from DUF920 (in the Pfam database) and COG3672. BTLCPs are predicted to possess the papain-like cysteine

Krzysztof Ginalski; Lisa Kinch; Leszek Rychlewski; Nick V. Grishin

2004-01-01

27

Linkage, Mobility, and Selfishness in the MazF Family of Bacterial Toxins: A Snapshot of Bacterial Evolution  

PubMed Central

Prokaryotic MazF family toxins cooccur with cognate antitoxins having divergent DNA-binding folds and can be of chromosomal or plasmid origin. Sequence similarity search was carried out to identify the Toxin–Antitoxin (TA) operons of MazF family followed by sequence analysis and phylogenetic studies. The genomic DNA upstream of the TA operons was searched for the presence of regulatory motifs. The MazF family toxins showed a conserved hydrophobic pocket in a multibinding site and are present in pathogenic bacteria. The toxins of the MazF family are associated with four main types of cognate antitoxin partners and cluster as a subfamily on the branches of the phylogenetic tree. This indicates that transmission of the entire operon is the dominant mode of inheritance. The plasmid borne TA modules were interspersed between the chromosomal TA modules of the same subfamily, compatible with a frequent interchange of TA genes between the chromosome and the plasmid akin to that observed for antibiotic resistance gens. The split network of the MazF family toxins showed the AbrB-linked toxins as a hub of horizontal gene transfer. Distinct motifs are present in the upstream region of each subfamily. The presence of MazF family TA modules in pathogenic bacteria and identification of a conserved binding pocket are significant for the development of novel antibacterials to disrupt the TA interaction. However, the role of TAs in stress resistance needs to be established. Phylogenetic studies provide insight into the evolution of MazF family TAs and effect on the bacterial genome. PMID:24265503

Chopra, Nikita; Saumitra; Pathak, Abhinandan; Bhatnagar, Rakesh; Bhatnagar, Sonika

2013-01-01

28

Associations and dynamics of Vibrionaceae in the environment, from the genus to the population level  

PubMed Central

The Vibrionaceae, which encompasses several potential pathogens, including V. cholerae, the causative agent of cholera, and V. vulnificus, the deadliest seafood-borne pathogen, are a well-studied family of marine bacteria that thrive in diverse habitats. To elucidate the environmental conditions under which vibrios proliferate, numerous studies have examined correlations with bulk environmental variables—e.g., temperature, salinity, nitrogen, and phosphate—and association with potential host organisms. However, how meaningful these environmental associations are remains unclear because data are fragmented across studies with variable sampling and analysis methods. Here, we synthesize findings about Vibrio correlations and physical associations using a framework of increasingly fine environmental and taxonomic scales, to better understand their dynamics in the wild. We first conduct a meta-analysis to determine trends with respect to bulk water environmental variables, and find that while temperature and salinity are generally strongly predictive correlates, other parameters are inconsistent and overall patterns depend on taxonomic resolution. Based on the hypothesis that dynamics may better correlate with more narrowly defined niches, we review evidence for specific association with plants, algae, zooplankton, and animals. We find that Vibrio are attached to many organisms, though evidence for enrichment compared to the water column is often lacking. Additionally, contrary to the notion that they flourish predominantly while attached, Vibrio can have, at least temporarily, a free-living lifestyle and even engage in massive blooms. Fine-scale sampling from the water column has enabled identification of such lifestyle preferences for ecologically cohesive populations, and future efforts will benefit from similar analysis at fine genetic and environmental sampling scales to describe the conditions, habitats, and resources shaping Vibrio dynamics. PMID:24575082

Takemura, Alison F.; Chien, Diana M.; Polz, Martin F.

2013-01-01

29

Associations and dynamics of Vibrionaceae in the environment, from the genus to the population level.  

PubMed

The Vibrionaceae, which encompasses several potential pathogens, including V. cholerae, the causative agent of cholera, and V. vulnificus, the deadliest seafood-borne pathogen, are a well-studied family of marine bacteria that thrive in a diverse habitats. To elucidate the environmental conditions under which vibrios proliferate, numerous studies have examined correlations with bulk environmental variables-e.g., temperature, salinity, nitrogen, and phosphate-and association with potential host organisms. However, how meaningful these environmental associations are remains unclear because data are fragmented across studies with variable sampling and analysis methods. Here, we synthesize findings about Vibrio correlations and physical associations using a framework of increasingly fine environmental and taxonomic scales, to better understand their dynamics in the wild. We first conduct a meta-analysis to determine trends with respect to bulk water environmental variables, and find that while temperature and salinity are generally strongly predictive correlates, other parameters are inconsistent and overall patterns depend on taxonomic resolution. Based on the hypothesis that dynamics may better correlate with more narrowly defined niches, we review evidence for specific association with plants, algae, zooplankton, and animals. We find that Vibrio are attached to many organisms, though evidence for enrichment compared to the water column is often lacking. Additionally, contrary to the notion that they flourish predominantly while attached, Vibrio can have, at least temporarily, a free-living lifestyle and even engage in massive blooms. Fine-scale sampling from the water column has enabled identification of such lifestyle preferences for ecologically cohesive populations, and future efforts will benefit from similar analysis at fine genetic and environmental sampling scales to describe the conditions, habitats, and resources shaping Vibrio dynamics. PMID:24575082

Takemura, Alison F; Chien, Diana M; Polz, Martin F

2014-01-01

30

Fluorogenic membrane overlays to enumerate total coliforms, Escherichia coli, and total Vibrionaceae in shellfish and seawater  

Technology Transfer Automated Retrieval System (TEKTRAN)

Three assays were developed to enumerate total coliforms, Escherichia coli, and total Vibrionaceae in shellfish and other foods and in seawater and other environmental samples. Assays involve membrane overlays of overnight colonies on non-selective agar plates to detect ß-glucuronidase and lysyl am...

31

BTLCP proteins: a novel family of bacterial transglutaminase-like cysteine proteinases.  

PubMed

Using sequence similarity searches and top-of-the-range fold-recognition methods, we have identified a novel family of bacterial transglutaminase-like cysteine proteinases (BTLCPs) with an invariant Cys-His-Asp catalytic triad and a predicted N-terminal signal sequence. This family of previously uncharacterized hypothetical proteins encompasses sequences of unknown function from DUF920 (in the Pfam database) and COG3672. BTLCPs are predicted to possess the papain-like cysteine proteinase fold and catalyze post-translational protein modification through transamidase, acetylase or hydrolase activity. Inspection of neighboring genes encoding BTLCPs suggests a link between this predicted activity and a type-I secretion system resembling ATP-binding cassette exporters of toxins and proteases involved in bacterial pathogenicity. PMID:15288868

Ginalski, Krzysztof; Kinch, Lisa; Rychlewski, Leszek; Grishin, Nick V

2004-08-01

32

Kinetic analysis of reverse transcriptase activity of bacterial family A DNA polymerases.  

PubMed

Some bacterial thermostable, wild-type or genetically engineered family A DNA polymerases have reverse transcriptase activity. However, difference in reverse transcriptase activities of family A DNA polymerases and retroviral reverse transcriptases (RTs) is unclear. In this study, comparative kinetic analysis was performed for the reverse transcriptase activities of the wild-type enzyme of family A DNA polymerase (M1pol(WT)) from Thermus thermophilus M1 and the variant enzyme of family A DNA polymerase (K4pol(L329A)), in which the mutation of Leu329?Ala is undertaken, from Thermotoga petrophila K4. In the incorporation of dTTP into poly(rA)-p(dT)(45), the reaction rates of K4pol(L329A) and M1pol(WT) exhibited a saturated profile of the Michaelis-Menten kinetics for dTTP concentrations but a substrate inhibition profile for poly(rA)-p(dT)(45) concentrations. In contrast, the reaction rates of Moloney murine leukemia virus (MMLV) RT exhibited saturated profiles for both dTTP and poly(rA)-p(dT)(45) concentrations. This suggests that high concentrations of DNA-primed RNA template decrease the efficiency of cDNA synthesis with bacterial family A DNA polymerases. PMID:23026053

Yasukawa, Kiyoshi; Konishi, Atsushi; Shinomura, Mayu; Nagaoka, Eriko; Fujiwara, Shinsuke

2012-10-26

33

Bacterial profiling of White Plague Disease in a comparative coral species framework  

PubMed Central

Coral reefs are threatened throughout the world. A major factor contributing to their decline is outbreaks and propagation of coral diseases. Due to the complexity of coral-associated microbe communities, little is understood in terms of disease agents, hosts and vectors. It is known that compromised health in corals is correlated with shifts in bacterial assemblages colonizing coral mucus and tissue. However, general disease patterns remain, to a large extent, ambiguous as comparative studies over species, regions, or diseases are scarce. Here, we compare bacterial assemblages of samples from healthy (HH) colonies and such displaying signs of White Plague Disease (WPD) of two different coral species (Pavona duerdeni and Porites lutea) from the same reef in Koh Tao, Thailand, using 16S rRNA gene microarrays. In line with other studies, we found an increase of bacterial diversity in diseased (DD) corals, and a higher abundance of taxa from the families that include known coral pathogens (Alteromonadaceae, Rhodobacteraceae, Vibrionaceae). In our comparative framework analysis, we found differences in microbial assemblages between coral species and coral health states. Notably, patterns of bacterial community structures from HH and DD corals were maintained over species boundaries. Moreover, microbes that differentiated the two coral species did not overlap with microbes that were indicative of HH and DD corals. This suggests that while corals harbor distinct species-specific microbial assemblages, disease-specific bacterial abundance patterns exist that are maintained over coral species boundaries. PMID:23924783

Roder, Cornelia; Arif, Chatchanit; Bayer, Till; Aranda, Manuel; Daniels, Camille; Shibl, Ahmed; Chavanich, Suchana; Voolstra, Christian R

2014-01-01

34

Bacterial profiling of White Plague Disease in a comparative coral species framework.  

PubMed

Coral reefs are threatened throughout the world. A major factor contributing to their decline is outbreaks and propagation of coral diseases. Due to the complexity of coral-associated microbe communities, little is understood in terms of disease agents, hosts and vectors. It is known that compromised health in corals is correlated with shifts in bacterial assemblages colonizing coral mucus and tissue. However, general disease patterns remain, to a large extent, ambiguous as comparative studies over species, regions, or diseases are scarce. Here, we compare bacterial assemblages of samples from healthy (HH) colonies and such displaying signs of White Plague Disease (WPD) of two different coral species (Pavona duerdeni and Porites lutea) from the same reef in Koh Tao, Thailand, using 16S rRNA gene microarrays. In line with other studies, we found an increase of bacterial diversity in diseased (DD) corals, and a higher abundance of taxa from the families that include known coral pathogens (Alteromonadaceae, Rhodobacteraceae, Vibrionaceae). In our comparative framework analysis, we found differences in microbial assemblages between coral species and coral health states. Notably, patterns of bacterial community structures from HH and DD corals were maintained over species boundaries. Moreover, microbes that differentiated the two coral species did not overlap with microbes that were indicative of HH and DD corals. This suggests that while corals harbor distinct species-specific microbial assemblages, disease-specific bacterial abundance patterns exist that are maintained over coral species boundaries. PMID:23924783

Roder, Cornelia; Arif, Chatchanit; Bayer, Till; Aranda, Manuel; Daniels, Camille; Shibl, Ahmed; Chavanich, Suchana; Voolstra, Christian R

2014-01-01

35

Defense Against Cannibalism: The SdpI Family of Bacterial Immunity/Signal Transduction Proteins  

PubMed Central

The SdpI family consists of putative bacterial toxin immunity and signal transduction proteins. One member of the family in Bacillus subtilis, SdpI, provides immunity to cells from cannibalism in times of nutrient limitation. SdpI family members are transmembrane proteins with 3, 4, 5, 6, 7, 8, or 12 putative transmembrane ?-helical segments (TMSs). These varied topologies appear to be genuine rather than artifacts due to sequencing or annotation errors. The basic and most frequently occurring element of the SdpI family has 6 TMSs. Homologues of all topological types were aligned to determine the homologous TMSs and loop regions, and the positive-inside rule was used to determine sidedness. The two most conserved motifs were identified between TMSs 1 and 2 and TMSs 4 and 5 of the 6 TMS proteins. These showed significant sequence similarity, leading us to suggest that the primordial precursor of these proteins was a 3 TMS–encoding genetic element that underwent intragenic duplication. Various deletional and fusional events, as well as intragenic duplications and inversions, may have yielded SdpI homologues with topologies of varying numbers and positions of TMSs. We propose a specific evolutionary pathway that could have given rise to these distantly related bacterial immunity proteins. We further show that genes encoding SdpI homologues often appear in operons with genes for homologues of SdpR, SdpI’s autorepressor. Our analyses allow us to propose structure–function relationships that may be applicable to most family members. Electronic supplementary material The online version of this article (doi:10.1007/s00232-010-9260-7) contains supplementary material, which is available to authorized users. PMID:20563570

Povolotsky, Tatyana Leonidovna; Orlova, Ekaterina; Tamang, Dorjee G.

2010-01-01

36

Defense against cannibalism: the SdpI family of bacterial immunity/signal transduction proteins.  

PubMed

The SdpI family consists of putative bacterial toxin immunity and signal transduction proteins. One member of the family in Bacillus subtilis, SdpI, provides immunity to cells from cannibalism in times of nutrient limitation. SdpI family members are transmembrane proteins with 3, 4, 5, 6, 7, 8, or 12 putative transmembrane alpha-helical segments (TMSs). These varied topologies appear to be genuine rather than artifacts due to sequencing or annotation errors. The basic and most frequently occurring element of the SdpI family has 6 TMSs. Homologues of all topological types were aligned to determine the homologous TMSs and loop regions, and the positive-inside rule was used to determine sidedness. The two most conserved motifs were identified between TMSs 1 and 2 and TMSs 4 and 5 of the 6 TMS proteins. These showed significant sequence similarity, leading us to suggest that the primordial precursor of these proteins was a 3 TMS-encoding genetic element that underwent intragenic duplication. Various deletional and fusional events, as well as intragenic duplications and inversions, may have yielded SdpI homologues with topologies of varying numbers and positions of TMSs. We propose a specific evolutionary pathway that could have given rise to these distantly related bacterial immunity proteins. We further show that genes encoding SdpI homologues often appear in operons with genes for homologues of SdpR, SdpI's autorepressor. Our analyses allow us to propose structure-function relationships that may be applicable to most family members. PMID:20563570

Povolotsky, Tatyana Leonidovna; Orlova, Ekaterina; Tamang, Dorjee G; Saier, Milton H

2010-06-01

37

Multidrug efflux pumps from Enterobacteriaceae, Vibrio cholerae and Staphylococcus aureus bacterial food pathogens.  

PubMed

Foodborne illnesses caused by bacterial microorganisms are common worldwide and constitute a serious public health concern. In particular, microorganisms belonging to the Enterobacteriaceae and Vibrionaceae families of Gram-negative bacteria, and to the Staphylococcus genus of Gram-positive bacteria are important causative agents of food poisoning and infection in the gastrointestinal tract of humans. Recently, variants of these bacteria have developed resistance to medically important chemotherapeutic agents. Multidrug resistant Escherichia coli, Salmonella enterica, Vibrio cholerae, Enterobacter spp., and Staphylococcus aureus are becoming increasingly recalcitrant to clinical treatment in human patients. Of the various bacterial resistance mechanisms against antimicrobial agents, multidrug efflux pumps comprise a major cause of multiple drug resistance. These multidrug efflux pump systems reside in the biological membrane of the bacteria and actively extrude antimicrobial agents from bacterial cells. This review article summarizes the evolution of these bacterial drug efflux pump systems from a molecular biological standpoint and provides a framework for future work aimed at reducing the conditions that foster dissemination of these multidrug resistant causative agents through human populations. PMID:25635914

Andersen, Jody L; He, Gui-Xin; Kakarla, Prathusha; K C, Ranjana; Kumar, Sanath; Lakra, Wazir Singh; Mukherjee, Mun Mun; Ranaweera, Indrika; Shrestha, Ugina; Tran, Thuy; Varela, Manuel F

2015-02-01

38

Multidrug Efflux Pumps from Enterobacteriaceae, Vibrio cholerae and Staphylococcus aureus Bacterial Food Pathogens  

PubMed Central

Foodborne illnesses caused by bacterial microorganisms are common worldwide and constitute a serious public health concern. In particular, microorganisms belonging to the Enterobacteriaceae and Vibrionaceae families of Gram-negative bacteria, and to the Staphylococcus genus of Gram-positive bacteria are important causative agents of food poisoning and infection in the gastrointestinal tract of humans. Recently, variants of these bacteria have developed resistance to medically important chemotherapeutic agents. Multidrug resistant Escherichia coli, Salmonella enterica, Vibrio cholerae, Enterobacter spp., and Staphylococcus aureus are becoming increasingly recalcitrant to clinical treatment in human patients. Of the various bacterial resistance mechanisms against antimicrobial agents, multidrug efflux pumps comprise a major cause of multiple drug resistance. These multidrug efflux pump systems reside in the biological membrane of the bacteria and actively extrude antimicrobial agents from bacterial cells. This review article summarizes the evolution of these bacterial drug efflux pump systems from a molecular biological standpoint and provides a framework for future work aimed at reducing the conditions that foster dissemination of these multidrug resistant causative agents through human populations. PMID:25635914

Andersen, Jody L.; He, Gui-Xin; Kakarla, Prathusha; KC, Ranjana; Kumar, Sanath; Lakra, Wazir Singh; Mukherjee, Mun Mun; Ranaweera, Indrika; Shrestha, Ugina; Tran, Thuy; Varela, Manuel F.

2015-01-01

39

Molecular evolution of the bacterial pseudouridine-5'-phosphate glycosidase protein family.  

PubMed

Pseudouridine is a noncanonical C-nucleoside commonly present in RNA, which is not metabolized in mammals, but can be recycled by the unique enzyme family of bacterial pseudouridine glycosidases such as YeiN from Escherichia coli. Here, we present rigorous bioinformatic and biochemical analyses of the protein family in order to find sequences that might code for nonpseudouridine glycosidase activities. To date, the only other function reported for the enzyme family occurs during the biosynthesis of the antibiotic alnumycin A in Streptomyces species, where AlnA functions as an unusual C-glycosynthase. Bioinformatics analysis of 755 protein sequences identified one group of sequences that were unlikely to harbour pseudouridine glycosidase activities. This observation was confirmed in vitro with one representative protein, IdgA from Streptomyces albus, which was unable to synthesize pseudouridine monophosphate, but was able to attach d-ribose-5-phosphate to juglone. Furthermore, our analyses provide evidence for horizontal gene transfer of pseudouridine glycosidases that may have occurred in Streptomyces and Doria species. Inspection of the genomic loci in the vicinity of pseudouridine glycosidases revealed that in 77% of the strains a kinase gene putatively involved in the phosphorylation of pseudouridine was found nearby, whereas the sequences encoding nonpseudouridine glycosidases coexisted with a phosphatase of the haloacid dehalogenase enzyme family. The investigation suggested that these unknown sequences might be involved in the biosynthesis of soluble blue pigments because of the presence of genes homologous to nonribosomal peptide synthetases. PMID:25081867

Thapa, Keshav; Oja, Terhi; Metsä-Ketelä, Mikko

2014-10-01

40

Novel cyclic di-GMP effectors of the YajQ protein family control bacterial virulence.  

PubMed

Bis-(3',5') cyclic di-guanylate (cyclic di-GMP) is a key bacterial second messenger that is implicated in the regulation of many critical processes that include motility, biofilm formation and virulence. Cyclic di-GMP influences diverse functions through interaction with a range of effectors. Our knowledge of these effectors and their different regulatory actions is far from complete, however. Here we have used an affinity pull-down assay using cyclic di-GMP-coupled magnetic beads to identify cyclic di-GMP binding proteins in the plant pathogen Xanthomonas campestris pv. campestris (Xcc). This analysis identified XC_3703, a protein of the YajQ family, as a potential cyclic di-GMP receptor. Isothermal titration calorimetry showed that the purified XC_3703 protein bound cyclic di-GMP with a high affinity (K(d)?2 µM). Mutation of XC_3703 led to reduced virulence of Xcc to plants and alteration in biofilm formation. Yeast two-hybrid and far-western analyses showed that XC_3703 was able to interact with XC_2801, a transcription factor of the LysR family. Mutation of XC_2801 and XC_3703 had partially overlapping effects on the transcriptome of Xcc, and both affected virulence. Electromobility shift assays showed that XC_3703 positively affected the binding of XC_2801 to the promoters of target virulence genes, an effect that was reversed by cyclic di-GMP. Genetic and functional analysis of YajQ family members from the human pathogens Pseudomonas aeruginosa and Stenotrophomonas maltophilia showed that they also specifically bound cyclic di-GMP and contributed to virulence in model systems. The findings thus identify a new class of cyclic di-GMP effector that regulates bacterial virulence. PMID:25329577

An, Shi-qi; Caly, Delphine L; McCarthy, Yvonne; Murdoch, Sarah L; Ward, Joseph; Febrer, Melanie; Dow, J Maxwell; Ryan, Robert P

2014-10-01

41

Novel Cyclic di-GMP Effectors of the YajQ Protein Family Control Bacterial Virulence  

PubMed Central

Bis-(3?,5?) cyclic di-guanylate (cyclic di-GMP) is a key bacterial second messenger that is implicated in the regulation of many critical processes that include motility, biofilm formation and virulence. Cyclic di-GMP influences diverse functions through interaction with a range of effectors. Our knowledge of these effectors and their different regulatory actions is far from complete, however. Here we have used an affinity pull-down assay using cyclic di-GMP-coupled magnetic beads to identify cyclic di-GMP binding proteins in the plant pathogen Xanthomonas campestris pv. campestris (Xcc). This analysis identified XC_3703, a protein of the YajQ family, as a potential cyclic di-GMP receptor. Isothermal titration calorimetry showed that the purified XC_3703 protein bound cyclic di-GMP with a high affinity (Kd?2 µM). Mutation of XC_3703 led to reduced virulence of Xcc to plants and alteration in biofilm formation. Yeast two-hybrid and far-western analyses showed that XC_3703 was able to interact with XC_2801, a transcription factor of the LysR family. Mutation of XC_2801 and XC_3703 had partially overlapping effects on the transcriptome of Xcc, and both affected virulence. Electromobility shift assays showed that XC_3703 positively affected the binding of XC_2801 to the promoters of target virulence genes, an effect that was reversed by cyclic di-GMP. Genetic and functional analysis of YajQ family members from the human pathogens Pseudomonas aeruginosa and Stenotrophomonas maltophilia showed that they also specifically bound cyclic di-GMP and contributed to virulence in model systems. The findings thus identify a new class of cyclic di-GMP effector that regulates bacterial virulence. PMID:25329577

An, Shi-qi; Caly, Delphine L.; McCarthy, Yvonne; Murdoch, Sarah L.; Ward, Joseph; Febrer, Melanie; Dow, J. Maxwell; Ryan, Robert P.

2014-01-01

42

A Novel Alkaliphilic Bacillus Esterase Belongs to the 13th Bacterial Lipolytic Enzyme Family  

PubMed Central

Background Microbial derived lipolytic hydrolysts are an important class of biocatalysts because of their huge abundance and ability to display bioactivities under extreme conditions. In spite of recent advances, our understanding of these enzymes remains rudimentary. The aim of our research is to advance our understanding by seeking for more unusual lipid hydrolysts and revealing their molecular structure and bioactivities. Methodology/Principal Findings Bacillus. pseudofirmus OF4 is an extreme alkaliphile with tolerance of pH up to 11. In this work we successfully undertook a heterologous expression of a gene estof4 from the alkaliphilic B. pseudofirmus sp OF4. The recombinant protein called EstOF4 was purified into a homologous product by Ni-NTA affinity and gel filtration. The purified EstOF4 was active as dimer with the molecular weight of 64 KDa. It hydrolyzed a wide range of substrates including p-nitrophenyl esters (C2–C12) and triglycerides (C2–C6). Its optimal performance occurred at pH 8.5 and 50°C towards p-nitrophenyl caproate and triacetin. Sequence alignment revealed that EstOF4 shared 71% identity to esterase Est30 from Geobacillus stearothermophilus with a typical lipase pentapeptide motif G91LS93LG95. A structural model developed from homology modeling revealed that EstOF4 possessed a typical esterase 6?/7? hydrolase fold and a cap domain. Site-directed mutagenesis and inhibition studies confirmed the putative catalytic triad Ser93, Asp190 and His220. Conclusion EstOF4 is a new bacterial esterase with a preference to short chain ester substrates. With a high sequence identity towards esterase Est30 and several others, EstOF4 was classified into the same bacterial lipolytic family, Family XIII. All the members in this family originate from the same bacterial genus, bacillus and display optimal activities from neutral pH to alkaline conditions with short and middle chain length substrates. However, with roughly 70% sequence identity, these enzymes showed hugely different thermal stabilities, indicating their diverse thermal adaptations via just changing a few amino acid residues. PMID:23577139

Rao, Lang; Xue, Yanfen; Zheng, Yingying; Lu, Jian R.; Ma, Yanhe

2013-01-01

43

A structural mechanism for bacterial autotransporter glycosylation by a dodecameric heptosyltransferase family  

PubMed Central

A large group of bacterial virulence autotransporters including AIDA-I from diffusely adhering E. coli (DAEC) and TibA from enterotoxigenic E. coli (ETEC) require hyperglycosylation for functioning. Here we demonstrate that TibC from ETEC harbors a heptosyltransferase activity on TibA and AIDA-I, defining a large family of bacterial autotransporter heptosyltransferases (BAHTs). The crystal structure of TibC reveals a characteristic ring-shape dodecamer. The protomer features an N-terminal ?-barrel, a catalytic domain, a ?-hairpin thumb, and a unique iron-finger motif. The iron-finger motif contributes to back-to-back dimerization; six dimers form the ring through ?-hairpin thumb-mediated hand-in-hand contact. The structure of ADP-D-glycero-?-D-manno-heptose (ADP-D,D-heptose)-bound TibC reveals a sugar transfer mechanism and also the ligand stereoselectivity determinant. Electron-cryomicroscopy analyses uncover a TibC–TibA dodecamer/hexamer assembly with two enzyme molecules binding to one TibA substrate. The complex structure also highlights a high efficient hyperglycosylation of six autotransporter substrates simultaneously by the dodecamer enzyme complex. DOI: http://dx.doi.org/10.7554/eLife.03714.001 PMID:25310236

Yao, Qing; Lu, Qiuhe; Wan, Xiaobo; Song, Feng; Xu, Yue; Hu, Mo; Zamyatina, Alla; Liu, Xiaoyun; Huang, Niu; Zhu, Ping; Shao, Feng

2014-01-01

44

A genomic perspective on a new bacterial genus and species from the Alcaligenaceae family, Basilea psittacipulmonis  

PubMed Central

Background A novel Gram-negative, non-haemolytic, non-motile, rod-shaped bacterium was discovered in the lungs of a dead parakeet (Melopsittacus undulatus) that was kept in captivity in a petshop in Basel, Switzerland. The organism is described with a chemotaxonomic profile and the nearly complete genome sequence obtained through the assembly of short sequence reads. Results Genome sequence analysis and characterization of respiratory quinones, fatty acids, polar lipids, and biochemical phenotype is presented here. Comparison of gene sequences revealed that the most similar species is Pelistega europaea, with BLAST identities of only 93% to the 16S rDNA gene, 76% identity to the rpoB gene, and a similar GC content (~43%) as the organism isolated from the parakeet, DSM 24701 (40%). The closest full genome sequences are those of Bordetella spp. and Taylorella spp. High-throughput sequencing reads from the Illumina-Solexa platform were assembled with the Edena de novo assembler to form 195 contigs comprising the ~2 Mb genome. Genome annotation with RAST, construction of phylogenetic trees with the 16S rDNA (rrs) gene sequence and the rpoB gene, and phylogenetic placement using other highly conserved marker genes with ML Tree all suggest that the bacterial species belongs to the Alcaligenaceae family. Analysis of samples from cages with healthy parakeets suggested that the newly discovered bacterial species is not widespread in parakeet living quarters. Conclusions Classification of this organism in the current taxonomy system requires the formation of a new genus and species. We designate the new genus Basilea and the new species psittacipulmonis. The type strain of Basilea psittacipulmonis is DSM 24701 (= CIP 110308 T, 16S rDNA gene sequence Genbank accession number JX412111 and GI 406042063). PMID:24581117

2014-01-01

45

Opa+ Neisseria gonorrhoeae exhibits reduced survival in human neutrophils via Src family kinase-mediated bacterial trafficking into mature phagolysosomes.  

PubMed

During gonorrhoeal infection, there is a heterogeneous population of Neisseria gonorrhoeae (Gc) varied in their expression of opacity-associated (Opa) proteins. While Opa proteins are important for bacterial attachment and invasion of epithelial cells, Opa+ Gc has a survival defect after exposure to neutrophils. Here, we use constitutively Opa- and OpaD+ Gc in strain background FA1090 to show that Opa+ Gc is more sensitive to killing inside adherent, chemokine-treated primary human neutrophils due to increased bacterial residence in mature, degradative phagolysosomes that contain primary and secondary granule antimicrobial contents. Although Opa+ Gc stimulates a potent oxidative burst, neutrophil killing of Opa+ Gc was instead attributable to non-oxidative components, particularly neutrophil proteases and the bactericidal/permeability-increasing protein. Blocking interaction of Opa+ Gc with carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) or inhibiting Src family kinase signalling, which is downstream of CEACAM activation, enhanced the survival of Opa+ Gc in neutrophils. Src family kinase signalling was required for fusion of Gc phagosomes with primary granules to generate mature phagolysosomes. Conversely, ectopic activation of Src family kinases or coinfection with Opa+ Gc resulted in decreased survival of Opa- Gc in neutrophils. From these results, we conclude that Opa protein expression is an important modulator of Gc survival characteristics in neutrophils by influencing phagosome dynamics and thus bacterial exposure to neutrophils' full antimicrobial arsenal. PMID:25346239

Johnson, M Brittany; Ball, Louise M; Daily, Kylene P; Martin, Jennifer N; Columbus, Linda; Criss, Alison K

2015-05-01

46

Rhodococcus sp. Strain CR-53 LipR, the First Member of a New Bacterial Lipase Family (Family X) Displaying an Unusual Y-Type Oxyanion Hole, Similar to the Candida antarctica Lipase Clan  

PubMed Central

Bacterial lipases constitute the most important group of biocatalysts for synthetic organic chemistry. Accordingly, there is substantial interest in developing new valuable lipases. Considering the lack of information concerning the lipases of the genus Rhodococcus and taking into account the interest raised by the enzymes produced by actinomycetes, a search for putative lipase-encoding genes from Rhodococcus sp. strain CR-53 was performed. We isolated, cloned, purified, and characterized LipR, the first lipase described from the genus Rhodococcus. LipR is a mesophilic enzyme showing preference for medium-chain-length acyl groups without showing interfacial activation. It displays good long-term stability and high tolerance for the presence of ions and chemical agents in the reaction mixture. Amino acid sequence analysis of LipR revealed that it displays four unique amino acid sequence motifs that clearly separate it from any other previously described family of bacterial lipases. Using bioinformatics tools, LipR could be related only to several uncharacterized putative lipases from different bacterial origins, all of which display the four blocks of consensus amino acid sequence motifs that contribute to define a new family of bacterial lipases, namely, family X. Therefore, LipR is the first characterized member of the new bacterial lipase family X. Further confirmation of this new family of lipases was performed after cloning Burkholderia cenocepacia putative lipase, bearing the same conserved motifs and clustering in family X. Interestingly, all lipases grouping in the new bacterial lipase family X display a Y-type oxyanion hole, a motif conserved in the Candida antarctica lipase clan but never found among bacterial lipases. This observation contributes to confirm that LipR and its homologs belong to a new family of bacterial lipases. PMID:22226953

Bassegoda, Arnau; Pastor, F. I. Javier

2012-01-01

47

Mining the bacterial unknown proteome: identification and characterization of a novel family of highly conserved protective antigens in Staphylococcus aureus.  

PubMed

In the human pathogen Staphylococcus aureus, there exists an enormous diversity of proteins containing DUFs (domains of unknown function). In the present study, we characterized the family of conserved staphylococcal antigens (Csa) classified as DUF576 and taxonomically restricted to Staphylococci. The 18 Csa paralogues in S. aureus Newman are highly similar at the sequence level, yet were found to be expressed in multiple cellular locations. Extracellular Csa1A was shown to be post-translationally processed and released. Molecular interaction studies revealed that Csa1A interacts with other Csa paralogues, suggesting that these proteins are involved in the same cellular process. The structures of Csa1A and Csa1B were determined by X-ray crystallography, unveiling a peculiar structure with limited structural similarity to other known proteins. Our results provide the first detailed biological characterization of this family and confirm the uniqueness of this family also at the structural level. We also provide evidence that Csa family members elicit protective immunity in in vivo animal models of staphylococcal infections, indicating a possible important role for these proteins in S. aureus biology and pathogenesis. These findings identify the Csa family as new potential vaccine candidates, and underline the importance of mining the bacterial unknown proteome to identify new targets for preventive vaccines. PMID:23895222

Schluepen, Christina; Malito, Enrico; Marongiu, Ambra; Schirle, Markus; McWhinnie, Elisabeth; Lo Surdo, Paola; Biancucci, Marco; Falugi, Fabiana; Nardi-Dei, Vincenzo; Marchi, Sara; Fontana, Maria Rita; Lombardi, Benedetta; De Falco, Maria Grazia; Rinaudo, C Daniela; Spraggon, Glen; Nissum, Mikkel; Bagnoli, Fabio; Grandi, Guido; Bottomley, Matthew J; Liberatori, Sabrina

2013-11-01

48

Molecular Mechanisms and Inhibition of Transcription Activation by Bacterial AraC Family Activator Proteins  

E-print Network

AraC family proteins are transcriptional regulators that are defined by the presence of a conserved DNA binding domain (DBD). My research focused on three AraC family activators: Rns (activator of virulence genes in diarrhea-causing ETEC), Vir...

Koppolu, Veerendra

2013-12-31

49

A bacterial type III effector family uses the papain-like hydrolytic activity to arrest the host cell cycle.  

PubMed

Pathogenic bacteria deliver effector proteins into host cells through the type III secretion apparatus to modulate the host function. We identify a family of proteins, homologous to the type III effector Cif from enteropathogenic Escherichia coli, in pathogens including Yersinia, Photorhabdus, and Burkholderia that contain functional type III secretion systems. Like Cif, this family of proteins is capable of arresting the host cell cycle at G(2)/M. Structure of one of the family members, Cif homolog in Burkholderia pseudomallei (CHBP), reveals a papain-like fold and a conserved Cys-His-Gln catalytic triad despite the lack of primary sequence identity. For CHBP and Cif, only the putative catalytic Cys is susceptible to covalent modification by E-64, a specific inhibitor of papain-like cysteine proteases. Unlike papain-like enzymes where the S2 site is the major determinant of cleavage-site specificity, CHBP has a characteristic negatively charged pocket occupying surface areas corresponding to the S1/S1' site in papain-like proteases. The negative charge is provided by a conserved aspartate, and the pocket best fits an arginine, as revealed by molecular docking analysis. Mutation analysis establishes the essential role of the catalytic triad and the negatively charged pocket in inducing cell cycle arrest in host cells. Our results demonstrate that bacterial pathogens have evolved a unique papain-like hydrolytic activity to block the normal host cell cycle progression. PMID:19225106

Yao, Qing; Cui, Jixin; Zhu, Yongqun; Wang, Guolun; Hu, Liyan; Long, Chengzu; Cao, Ran; Liu, Xinqi; Huang, Niu; Chen, She; Liu, Liping; Shao, Feng

2009-03-10

50

IDENTIFICATION OF NICOTINAMIDE MONONUCLEOTIDE DEAMIDASE OF THE BACTERIAL PYRIDINE NUCLEOTIDE CYCLE REVEALS A NOVEL BROADLY CONSERVED AMIDOHYDROLASE FAMILY  

SciTech Connect

The pyridine nucleotide cycle (PNC) is a network of salvage and recycling routes maintaining homeostasis of NAD(P) cofactor pool in the cell. Nicotinamide mononucleotide (NMN) deamidase (EC 3.5.1.42), one of the key enzymes of the bacterial PNC was originally described in Enterobacteria, but the corresponding gene eluded identification for over 30 years. A genomics-based reconstruction of NAD metabolism across hundreds bacterial species suggested that NMN deamidase reaction is the only possible way of nicotinamide salvage in the marine bacterium Shewanella oneidensis. This prediction was verified via purification of native NMN deamidase from S. oneidensis followed by the identification of the respective gene, termed pncC. Enzymatic characterization of the PncC protein, as well as phenotype analysis of deletion mutants, confirmed its proposed biochemical and physiological function in S. oneidensis. Of the three PncC homologs present in E. coli, NMN deamidase activity was confirmed only for the recombinant purified product of the ygaD gene. A comparative analysis at the level of sequence and three dimensional structure, which is available for one of the PncC family member, shows no homology with any previously described amidohydrolases. Multiple alignment analysis of functional and non functional PncC homologs, together with NMN docking experiments, allowed us to tentatively identify the active site area and conserved residues therein. An observed broad phylogenomic distribution of predicted functional PncCs in bacterial kingdom is consistent with a possible role in detoxification of NMN, resulting from NAD utilization by DNA ligase.

Galeazzi, Luca; Bocci, Paolo; Amici, Adolfo; Brunetti, Lucia; Ruggieri, Silverio; Romine, Margaret F.; Reed, Samantha B.; Osterman, Andrei; Rodionov, Dmitry A.; Sorci, Leonardo; Raffaelli, Nadia

2011-09-27

51

A family of conserved bacterial effectors inhibits salicylic acid-mediated basal immunity and promotes disease necrosis in plants  

PubMed Central

Salicylic acid (SA)-mediated host immunity plays a central role in combating microbial pathogens in plants. Inactivation of SA-mediated immunity, therefore, would be a critical step in the evolution of a successful plant pathogen. It is known that mutations in conserved effector loci (CEL) in the plant pathogens Pseudomonas syringae (the ?CEL mutation), Erwinia amylovora (the dspA/E mutation), and Pantoea stewartii subsp. stewartii (the wtsE mutation) exert particularly strong negative effects on bacterial virulence in their host plants by unknown mechanisms. We found that the loss of virulence in ?CEL and dspA/E mutants was linked to their inability to suppress cell wall-based defenses and to cause normal disease necrosis in Arabidopsis and apple host plants. The ?CEL mutant activated SA-dependent callose deposition in wild-type Arabidopsis but failed to elicit high levels of callose-associated defense in Arabidopsis plants blocked in SA accumulation or synthesis. This mutant also multiplied more aggressively in SA-deficient plants than in wild-type plants. The hopPtoM and avrE genes in the CEL of P. syringae were found to encode suppressors of this SA-dependent basal defense. The widespread conservation of the HopPtoM and AvrE families of effectors in various bacteria suggests that suppression of SA-dependent basal immunity and promotion of host cell death are important virulence strategies for bacterial infection of plants. PMID:15210989

DebRoy, Sruti; Thilmony, Roger; Kwack, Yong-Bum; Nomura, Kinya; He, Sheng Yang

2004-01-01

52

Sphingomonas paucimobilis beta-glucosidase Bgl1: a member of a new bacterial subfamily in glycoside hydrolase family 1.  

PubMed Central

The Sphingomonas paucimobilis beta-glucosidase Bgl1 is encoded by the bgl1 gene, associated with an 1308 bp open reading frame. The deduced protein has a potential signal peptide of 24 amino acids in the N-terminal region, and experimental evidence is consistent with the processing and export of the Bgl1 protein through the inner membrane to the periplasmic space. A His(6)-tagged 44.3 kDa protein was over-produced in the cytosol of Escherichia coli from a recombinant plasmid, which contained the S. paucimobilis bgl1 gene lacking the region encoding the putative signal peptide. Mature beta-glucosidase Bgl1 is specific for aryl-beta-glucosides and has no apparent activity with oligosaccharides derived from cellulose hydrolysis and other saccharides. A structure-based alignment established structural relations between S. paucimobilis Bgl1 and other members of the glycoside hydrolase (GH) family 1 enzymes. At subsite -1, the conserved residues required for catalysis by GH1 enzymes are present in Bgl1 with only minor differences. Major differences are found at subsite +1, the aglycone binding site. This alignment seeded a sequence-based phylogenetic analysis of GH1 enzymes, revealing an absence of horizontal transfer between phyla. Bootstrap analysis supported the definition of subfamilies and revealed that Bgl1, the first characterized beta-glucosidase from the genus Sphingomonas, represents a very divergent bacterial subfamily, closer to archaeal subfamilies than to others of bacterial origin. PMID:12444924

Marques, Ana Rita; Coutinho, Pedro M; Videira, Paula; Fialho, Arsénio M; Sá-Correia, Isabel

2003-01-01

53

Ultrastructural and molecular characterization of a bacterial symbiosis in the ecologically important scale insect family Coelostomidiidae.  

PubMed

Scale insects are important ecologically and as agricultural pests. The majority of scale insect taxa feed exclusively on plant phloem sap, which is carbon rich but deficient in essential amino acids. This suggests that, as seen in the related aphids and psyllids, scale insect nutrition might also depend upon bacterial symbionts, yet very little is known about scale insect-bacteria symbioses. We report here the first identification and molecular characterization of symbiotic bacteria associated with the New Zealand giant scale Coelostomidia wairoensis, using fluorescence in situ hybridization (FISH), transmission electron microscopy (TEM) and 16S rRNA gene-based analysis. Dissection and FISH confirmed the location of the bacteria in large, paired, multilobate organs in the abdominal region of the insect. TEM indicated that the dominant pleomorphic bacteria were confined to bacteriocytes in the sheath-enclosed bacteriome. Phylogenetic analysis revealed the presence of three distinct bacterial types, the bacteriome-associated B-symbiont (Bacteroidetes), an Erwinia-related symbiont (Gammaproteobacteria) and Wolbachia sp. (Alphaproteobacteria). This study extends the current knowledge of scale insect symbionts and is the first microbiological investigation of the ecologically important coelostomidiid scales. PMID:22468989

Dhami, Manpreet K; Turner, Adrian P; Deines, Peter; Beggs, Jacqueline R; Taylor, Michael W

2012-09-01

54

The Bacterial Intimins and Invasins: A Large and Novel Family of Secreted Proteins  

Microsoft Academic Search

BackgroundGram-negative bacteria have developed a limited repertoire of solutions for secreting proteins from the cytoplasmic compartment to the exterior of the cell. Amongst the spectrum of secreted proteins are the intimins and invasins (the Int\\/Inv family; TC# 1.B.54) which are characterized by an N-terminal ?-barrel domain and a C-terminal surface localized passenger domain. Despite the important role played by members

Jennifer C. Tsai; Ming-Ren Yen; Rostislav Castillo; Denisse L. Leyton; Ian R. Henderson; Milton H. Saier; Hendrik W. van Veen

2010-01-01

55

Broad Spectrum Activity of a Lectin-Like Bacterial Serine Protease Family on Human Leukocytes  

PubMed Central

The serine protease autotransporter from Enterobacteriaceae (SPATE) family, which number more than 25 proteases with apparent diverse functions, have been phylogenetically divided into two distinct classes, designated 1 and 2. We recently demonstrated that Pic and Tsh, two members of the class-2 SPATE family produced by intestinal and extraintestinal pathogenic E. coli, were able to cleave a number of O-glycosylated proteins on neutrophils and lymphocytes resulting in impaired leukocyte functions. Here we show that most members of the class-2 SPATE family have lectin-like properties and exhibit differential protease activity reliant on glycoprotein type and cell lineage. Protease activity was seen in virtually all tested O-glycosylated proteins including CD34, CD55, CD164, TIM1, TIM3, TIM4 and C1-INH. We also show that although SPATE proteins bound and cleaved glycoproteins more efficiently on granulocytes and monocytes, they also targeted glycoproteins on B, T and natural killer lymphocytes. Finally, we found that the characteristic domain-2 of class-2 SPATEs is not required for glycoprotease activity, but single amino acid mutations in Pic domain-1 to those residues naturally occurring in domain-1 of SepA, were sufficient to hamper Pic glycoprotease activity. This study shows that most class-2 SPATEs have redundant activities and suggest that they may function as immunomodulators at several levels of the immune system. PMID:25251283

Ayala-Lujan, Jorge Luis; Vijayakumar, Vidhya; Gong, Mei; Smith, Rachel; Santiago, Araceli E.; Ruiz-Perez, Fernando

2014-01-01

56

Chloroplast division in higher plants requires members of two functionally divergent gene families with homology to bacterial ftsZ.  

PubMed Central

The division of plastids is critical for viability in photosynthetic eukaryotes, but the mechanisms associated with this process are still poorly understood. We previously identified a nuclear gene from Arabidopsis encoding a chloroplast-localized homolog of the bacterial cell division protein FtsZ, an essential cytoskeletal component of the prokaryotic cell division apparatus. Here, we report the identification of a second nuclear-encoded FtsZ-type protein from Arabidopsis that does not contain a chloroplast targeting sequence or other obvious sorting signals and is not imported into isolated chloroplasts, which strongly suggests that it is localized in the cytosol. We further demonstrate using antisense technology that inhibiting expression of either Arabidopsis FtsZ gene (AtFtsZ1-1 or AtFtsZ2-1) in transgenic plants reduces the number of chloroplasts in mature leaf cells from 100 to one, indicating that both genes are essential for division of higher plant chloroplasts but that each plays a distinct role in the process. Analysis of currently available plant FtsZ sequences further suggests that two functionally divergent FtsZ gene families encoding differentially localized products participate in chloroplast division. Our results provide evidence that both chloroplastic and cytosolic forms of FtsZ are involved in chloroplast division in higher plants and imply that important differences exist between chloroplasts and prokaryotes with regard to the roles played by FtsZ proteins in the division process. PMID:9836740

Osteryoung, K W; Stokes, K D; Rutherford, S M; Percival, A L; Lee, W Y

1998-01-01

57

Functional role of oligomerization for bacterial and plant SWEET sugar transporter family  

PubMed Central

Eukaryotic sugar transporters of the MFS and SWEET superfamilies consist of 12 and 7 ?-helical transmembrane domains (TMs), respectively. Structural analyses indicate that MFS transporters evolved from a series of tandem duplications of an ancestral 3-TM unit. SWEETs are heptahelical proteins carrying a tandem repeat of 3-TM separated by a single TM. Here, we show that prokaryotes have ancestral SWEET homologs with only 3-TM and that the Bradyrhizobium japonicum SemiSWEET1, like Arabidopsis SWEET11, mediates sucrose transport. Eukaryotic SWEETs most likely evolved by internal duplication of the 3-TM, suggesting that SemiSWEETs form oligomers to create a functional pore. However, it remains elusive whether the 7-TM SWEETs are the functional unit or require oligomerization to form a pore sufficiently large to allow for sucrose passage. Split ubiquitin yeast two-hybrid and split GFP assays indicate that Arabidopsis SWEETs homo- and heterooligomerize. We examined mutant SWEET variants for negative dominance to test if oligomerization is necessary for function. Mutation of the conserved Y57 or G58 in SWEET1 led to loss of activity. Coexpression of the defective mutants with functional A. thaliana SWEET1 inhibited glucose transport, indicating that homooligomerization is necessary for function. Collectively, these data imply that the basic unit of SWEETs, similar to MFS sugar transporters, is a 3-TM unit and that a functional transporter contains at least four such domains. We hypothesize that the functional unit of the SWEET family of transporters possesses a structure resembling the 12-TM MFS structure, however, with a parallel orientation of the 3-TM unit. PMID:24027245

Xuan, Yuan Hu; Hu, Yi Bing; Chen, Li-Qing; Sosso, Davide; Ducat, Daniel C.; Hou, Bi-Huei; Frommer, Wolf B.

2013-01-01

58

Aminoacetone oxidase from Streptococcus oligofermentans belongs to a new three-domain family of bacterial flavoproteins.  

PubMed

The aaoSo gene from Streptococcus oligofermentans encodes a 43 kDa flavoprotein, aminoacetone oxidase (SoAAO), which was reported to possess a low catalytic activity against several different L-amino acids; accordingly, it was classified as an L-amino acid oxidase. Subsequently, SoAAO was demonstrated to oxidize aminoacetone (a pro-oxidant metabolite), with an activity ~25-fold higher than the activity displayed on L-lysine, thus lending support to the assumption of aminoacetone as the preferred substrate. In the present study, we have characterized the SoAAO structure-function relationship. SoAAO is an FAD-containing enzyme that does not possess the classical properties of the oxidase/dehydrogenase class of flavoproteins (i.e. no flavin semiquinone formation is observed during anaerobic photoreduction as well as no reaction with sulfite) and does not show a true L-amino acid oxidase activity. From a structural point of view, SoAAO belongs to a novel protein family composed of three domains: an ?/? domain corresponding to the FAD-binding domain, a ?-domain partially modulating accessibility to the coenzyme, and an additional ?-domain. Analysis of the reaction products of SoAAO on aminoacetone showed 2,5-dimethylpyrazine as the main product; we propose that condensation of two aminoacetone molecules yields 3,6-dimethyl-2,5-dihydropyrazine that is subsequently oxidized to 2,5-dimethylpyrazine. The ability of SoAAO to bind two molecules of the substrate analogue O-methylglycine ligand is thought to facilitate the condensation reaction. A specialized role for SoAAO in the microbial defence mechanism related to aminoacetone catabolism through a pathway yielding dimethylpyrazine derivatives instead of methylglyoxal can be proposed. PMID:25269103

Molla, Gianluca; Nardini, Marco; Motta, Paolo; D'Arrigo, Paola; Panzeri, Walter; Pollegioni, Loredano

2014-12-15

59

Functional role of oligomerization for bacterial and plant SWEET sugar transporter family.  

PubMed

Eukaryotic sugar transporters of the MFS and SWEET superfamilies consist of 12 and 7 ?-helical transmembrane domains (TMs), respectively. Structural analyses indicate that MFS transporters evolved from a series of tandem duplications of an ancestral 3-TM unit. SWEETs are heptahelical proteins carrying a tandem repeat of 3-TM separated by a single TM. Here, we show that prokaryotes have ancestral SWEET homologs with only 3-TM and that the Bradyrhizobium japonicum SemiSWEET1, like Arabidopsis SWEET11, mediates sucrose transport. Eukaryotic SWEETs most likely evolved by internal duplication of the 3-TM, suggesting that SemiSWEETs form oligomers to create a functional pore. However, it remains elusive whether the 7-TM SWEETs are the functional unit or require oligomerization to form a pore sufficiently large to allow for sucrose passage. Split ubiquitin yeast two-hybrid and split GFP assays indicate that Arabidopsis SWEETs homo- and heterooligomerize. We examined mutant SWEET variants for negative dominance to test if oligomerization is necessary for function. Mutation of the conserved Y57 or G58 in SWEET1 led to loss of activity. Coexpression of the defective mutants with functional A. thaliana SWEET1 inhibited glucose transport, indicating that homooligomerization is necessary for function. Collectively, these data imply that the basic unit of SWEETs, similar to MFS sugar transporters, is a 3-TM unit and that a functional transporter contains at least four such domains. We hypothesize that the functional unit of the SWEET family of transporters possesses a structure resembling the 12-TM MFS structure, however, with a parallel orientation of the 3-TM unit. PMID:24027245

Xuan, Yuan Hu; Hu, Yi Bing; Chen, Li-Qing; Sosso, Davide; Ducat, Daniel C; Hou, Bi-Huei; Frommer, Wolf B

2013-09-24

60

Rice bacterial blight pathogen Xanthomonas oryzae pv. oryzae produces multiple DSF-family signals in regulation of virulence factor production  

PubMed Central

Background Xanthomonas oryzae pv. oryzae (Xoo) is the causal agent of rice bacterial blight disease. Xoo produces a range of virulence factors, including EPS, extracellular enzyme, iron-chelating siderophores, and type III-secretion dependent effectors, which are collectively essential for virulence. Genetic and genomics evidence suggest that Xoo might use the diffusible signal factor (DSF) type quorum sensing (QS) system to regulate the virulence factor production. However, little is known about the chemical structure of the DSF-like signal(s) produced by Xoo and the factors influencing the signal production. Results Xoo genome harbours an rpf cluster comprising rpfB, rpfF, rpfC and rpfG. The proteins encoded by these genes are highly homologous to their counterparts in X. campestris pv. campestris (Xcc), suggesting that Xcc and Xoo might use similar mechanisms for DSF biosynthesis and autoregulation. Consistent with in silico analysis, the rpfF mutant was DSF-deficient and the rpfC mutant produced about 25 times higher DSF-like activity than the wild type Xoo strain KACC10331. From the supernatants of rpfC mutant, we purified three compounds showing strong DSF-like activity. Mass spectrometry and NMR analysis revealed that two of them were the previously characterized DSF and BDSF; the third one was a novel unsaturated fatty acid with 2 double bonds and was designated as CDSF in this study. Further analysis showed that all the three DSF-family signals were synthesized via the enzyme RpfF encoded by Xoo2868. DSF and BDSF at a final concentration of 3 ?M to the rpfF mutant could fully restore its extracellular xylanase activity and EPS production to the wild type level, but CDSF was less active than DSF and BDSF in induction of EPS and xylanase. DSF and CDSF shared a similar cell density-dependent production time course with the maximum production being detected at 42 h after inoculation, whereas the maximum production of BDSF was observed at 36 h after inoculation. When grown in a rich medium such as YEB, LB, PSA, and NYG, Xoo produced all the three signals with the majority being DSF. Whereas in nutritionally poor XOLN medium Xoo only produced BDSF and DSF but the majority was BDSF. Conclusions This study demonstrates that Xoo and Xcc share the conserved mechanisms for DSF biosynthesis and autoregulation. Xoo produces DSF, BDSF and CDSF signals in rich media and CDSF is a novel signal in DSF-family with two double bonds. All the three DSF-family signals promote EPS production and xylanase activity in Xoo, but CDSF is less active than its analogues DSF and BDSF. The composition and ratio of the three DSF-family signals produced by Xoo are influenced by the composition of culture media. PMID:20615263

2010-01-01

61

Exploring the reactivity of bacterial multicomponent monooxygenases  

E-print Network

Chapter 1. Introduction: The Reactivity of Bacterial Multicomponent Monooxygenases Bacterial multicomponent monooxygenases constitute a remarkable family of enzymes that oxidize small, inert hydrocarbon substrates using ...

Tinberg, Christine Elaine

2010-01-01

62

Role of Key Salt Bridges in Thermostability of G. thermodenitrificans EstGtA2: Distinctive Patterns within the New Bacterial Lipolytic Enzyme Family XV  

PubMed Central

Bacterial lipolytic enzymes were originally classified into eight different families defined by Arpigny and Jaeger (families I-VIII). Recently, the discovery of new lipolytic enzymes allowed for extending the original classification to fourteen families (I-XIV). We previously reported that G. thermodenitrificans EstGtA2 (access no. AEN92268) belonged to a novel group of bacterial lipolytic enzymes. Here we propose a 15th family (family XV) and suggest criteria for the assignation of protein sequences to the N’ subfamily. Five selected salt bridges, hallmarks of the N’ subfamily (E3/R54, E12/R37, E66/R140, D124/K178 and D205/R220) were disrupted in EstGtA2 using a combinatorial alanine-scanning approach. A set of 14 (R/K?A) mutants was produced, including five single, three double, three triple and three quadruple mutants. Despite a high tolerance to non-conservative mutations for folding, all the alanine substitutions were destabilizing (decreasing Tm by 5 to 14°C). A particular combination of four substitutions exceeded this tolerance and prevents the correct folding of EstGtA2, leading to enzyme inactivation. Although other mutants remain active at low temperatures, the accumulation of more than two mutations had a dramatic impact on EstGtA2 activity at high temperatures suggesting an important role of these conserved salt bridge-forming residues in thermostability of lipolytic enzymes from the N’ subfamily. We also identified a particular interloop salt bridge in EstGtA2 (D194/H222), located at position i -2 and i -4 residues from the catalytic Asp and His respectively which is conserved in other related bacterial lipolytic enzymes (families IV and XIII) with high tolerance to mutations and charge reversal. We investigated the role of residue identity at position 222 in controlling stability-pH dependence in EstGtA2. The introduction of a His to Arg mutation led to increase thermostability under alkaline pH. Our results suggest primary targets for optimization of EstGtA2 for specific biotechnological purposes. PMID:24116134

Charbonneau, David M.; Beauregard, Marc

2013-01-01

63

Role of key salt bridges in thermostability of G. thermodenitrificans EstGtA2: distinctive patterns within the new bacterial lipolytic enzyme family XV.  

PubMed

Bacterial lipolytic enzymes were originally classified into eight different families defined by Arpigny and Jaeger (families I-VIII). Recently, the discovery of new lipolytic enzymes allowed for extending the original classification to fourteen families (I-XIV). We previously reported that G. thermodenitrificans EstGtA2 (access no. AEN92268) belonged to a novel group of bacterial lipolytic enzymes. Here we propose a 15(th) family (family XV) and suggest criteria for the assignation of protein sequences to the N' subfamily. Five selected salt bridges, hallmarks of the N' subfamily (E3/R54, E12/R37, E66/R140, D124/K178 and D205/R220) were disrupted in EstGtA2 using a combinatorial alanine-scanning approach. A set of 14 (R/K?A) mutants was produced, including five single, three double, three triple and three quadruple mutants. Despite a high tolerance to non-conservative mutations for folding, all the alanine substitutions were destabilizing (decreasing T m by 5 to 14°C). A particular combination of four substitutions exceeded this tolerance and prevents the correct folding of EstGtA2, leading to enzyme inactivation. Although other mutants remain active at low temperatures, the accumulation of more than two mutations had a dramatic impact on EstGtA2 activity at high temperatures suggesting an important role of these conserved salt bridge-forming residues in thermostability of lipolytic enzymes from the N' subfamily. We also identified a particular interloop salt bridge in EstGtA2 (D194/H222), located at position i -2 and i -4 residues from the catalytic Asp and His respectively which is conserved in other related bacterial lipolytic enzymes (families IV and XIII) with high tolerance to mutations and charge reversal. We investigated the role of residue identity at position 222 in controlling stability-pH dependence in EstGtA2. The introduction of a His to Arg mutation led to increase thermostability under alkaline pH. Our results suggest primary targets for optimization of EstGtA2 for specific biotechnological purposes. PMID:24116134

Charbonneau, David M; Beauregard, Marc

2013-01-01

64

Astrocytes Produce IL-19 in Response to Bacterial Challenge and are Sensitive to the Immunosuppressive Effects of this IL-10 Family Member  

PubMed Central

There is growing appreciation that resident glial cells can initiate and/or regulate inflammation following trauma or infection in the central nervous system (CNS). We have previously demonstrated the ability of microglia and astrocytes to respond to bacterial pathogens or their products by rapid production of inflammatory mediators, followed by the production of the immunosuppressive cytokine interleukin (IL)210. IL-19, another member of the IL-10 family of cytokines, has been studied in the context of a number of inflammatory conditions in the periphery and is known to modulate immune cell activity. In the present study, we demonstrate the constitutive and/or inducible expression of IL-19 and its cognate receptor subunits, IL-19R? and IL-19R? (also known as IL-20R1 and IL-20R2, and IL-20RA and IL-20RB), in mouse brain tissue, and by primary murine and human astrocytes. We also provide evidence for the presence of a novel truncated IL-19R? transcript variant in mouse brain tissue, but not glial cells, that shows reduced expression following bacterial infection. Importantly, IL-19R functionality in GLIA is indicated by the ability of IL-19 to regulate signaling component expression in these cells. Furthermore, while IL-19 itself had no effect on glial cytokine production, IL-19 treatment of bacterially infected or Toll-like receptor ligand stimulated astrocytes significantly attenuated pro-inflammatory cytokine production. The bacterially induced production of IL-19 by these resident CNS cells, the constitutive expression of its cognate receptor subunits, and the immunomodulatory effects of this cytokine, suggest a novel mechanism by which astrocytes can regulate CNS inflammation. PMID:24677051

Cooley, Ian D.; Chauhan, Vinita S.; Donneyz, Miguel A.; Marriott, Ian

2014-01-01

65

A bacterial type III effector family uses the papain-like hydrolytic activity to arrest the host cell cycle  

Microsoft Academic Search

Pathogenic bacteria deliver effector proteins into host cells through the type III secretion apparatus to modulate the host function. We identify a family of proteins, homologous to the type III effector Cif from enteropathogenic Escherichia coli, in pathogens including Yersinia, Photorhabdus, and Burkholderia that contain functional type III secretion systems. Like Cif, this family of proteins is capable of arresting

Qing Yao; Jixin Cui; Yongqun Zhu; Guolun Wang; Liyan Hu; Chengzu Long; Ran Cao; Xinqi Liu; Niu Huang; She Chen; Liping Liu; Feng Shao

2009-01-01

66

Molecular analyses of the rice tubby-like protein gene family and their response to bacterial infection  

Microsoft Academic Search

Tubby-like protein family has been identified in various multicellular organisms, indicating its fundamental functions in\\u000a the organisms. However, the roles of plant tubby-like proteins are unknown. In this study, we have defined the tubby-like\\u000a protein gene (OsTLP) family with 14 members in rice. Most of the OsTLPs harbor a tubby domain in their carboxyl terminus and an F-box domain\\u000a in

Yanjun Kou; Deyun Qiu; Lei Wang; Xianghua Li; Shiping Wang

2009-01-01

67

Phylogenetic, structural and functional analyses of the LacI-GalR family of bacterial transcription factors  

Microsoft Academic Search

Phylogenetic tree construction for 25 sequenced members of the LacI-GalR family (LGF) of transcription factors revealed that almost all branches are similar in length, radiating essentially from a single point. This observation suggests that most of these proteins arose by duplication events which occurred at a specific time in evolutionary history, and that further duplication events were rare. Analyses of

Chuck Chuong Nguyen; Milton H. Saier

1995-01-01

68

Diversity of Symbiotic Organs and Bacterial Endosymbionts of Lygaeoid Bugs of the Families Blissidae and Lygaeidae (Hemiptera: Heteroptera: Lygaeoidea)  

PubMed Central

Here we present comparative data on the localization and identity of intracellular symbionts among the superfamily Lygaeoidea (Insecta: Hemiptera: Heteroptera: Pentatomomorpha). Five different lygaeoid species from the families Blissidae and Lygaeidae (sensu stricto; including the subfamilies Lygaeinae and Orsillinae) were analyzed. Fluorescence in situ hybridization (FISH) revealed that all the bugs studied possess paired bacteriomes that are differently shaped in the abdomen and harbor specific endosymbionts therein. The endosymbionts were also detected in female gonads and at the anterior poles of developing eggs, indicating vertical transmission of the endosymbionts via ovarial passage, in contrast to the posthatch symbiont transmission commonly found among pentatomoid bugs (Pentatomomorpha: Pentatomoidea). Phylogenetic analysis based on 16S rRNA and groEL genes showed that the endosymbionts of Ischnodemus sabuleti, Arocatus longiceps, Belonochilus numenius, Orsillus depressus, and Ortholomus punctipennis constitute at least four distinct clades in the Gammaproteobacteria. The endosymbiont phylogeny did not agree with the host phylogeny based on the mitochondrial cytochrome oxidase I (COI) gene, but there was a local cospeciating pattern within the subfamily Orsillinae. Meanwhile, the endosymbiont of Belonochilus numenius (Lygaeidae: Orsillinae), although harbored in paired bacteriomes as in other lygaeoid bugs of the related genera Nysius, Ortholomus, and Orsillus, was phylogenetically close to “Candidatus Rohrkolberia cinguli,” the endosymbiont of Chilacis typhae (Lygaeoidea: Artheneidae), suggesting an endosymbiont replacement in this lineage. The diverse endosymbionts and the differently shaped bacteriomes may reflect independent evolutionary origins of the endosymbiotic systems among lygaeoid bugs. PMID:22307293

Renz, Patricia; Dettner, Konrad; Kehl, Siegfried

2012-01-01

69

Expanding the family of collagen proteins: Recombinant bacterial collagens of varying composition form triple-helices of similar stability  

PubMed Central

The presence of the (Gly-Xaa-Yaa)n open reading frames in different bacteria predicts the existence of an expanded family of collagen-like proteins. To further explore the triple-helix motif and stabilization mechanisms in the absence of hydroxyproline (Hyp), predicted novel collagen-like proteins from Gram-positive and -negative bacteria were expressed in Escherichia coli and characterized. Soluble proteins capable of successful folding and in vitro refolding were observed for collagen proteins from Methylobacterium sp 4-46, Rhodopseudomonas palustris and Solibacter usitatus. In contrast, all protein constructs from Clostridium perfringens were found predominantly in inclusion bodies. However, attachment of a heterologous N-terminal or C-terminal non-collagenous folding domain induced the Clostridium perfringens collagen domain to fold and become soluble. The soluble constructs from different bacteria had typical collagen triple-helical features and showed surprisingly similar thermal stabilities despite diverse amino acid compositions. These collagen-like proteins provide a resource for the development of biomaterials with new properties. PMID:20025291

Xu, Chunying; Yu, Zhuoxin; Inouye, Masayori; Brodsky, Barbara; Mirochnitchenko, Oleg

2010-01-01

70

Identification of a new steroid degrading bacterial strain H5 from the Baltic Sea and isolation of two estradiol inducible genes.  

PubMed

The presence of steroid hormones in the aquatic environment is potentially threatening the population dynamics of all kinds of sea animals and public health. Environmental estrogens in water have been reported to be associated with abnormal sexual development and abnormal feminizing responses in some animals. New approaches for the bioremediation of steroid hormones from the environment are therefore urgently sought. We have previously isolated a steroid degrading bacterial strain (H5) from the Baltic Sea, at Kiel, Germany. In the present investigation, 16S rRNA analysis showed that marine strain H5 belongs to the genus Vibrio, family Vibrionaceae and class Gamma-Proteobacteria. To enable identification of steroid inducible genes from bacterial strain H5, a library was constructed of H5 chromosomal DNA fragments cloned into a fluorescent reporter (pKEGFP-2). A reporter plasmid pK3?-4.6-EGFP3 containing the estrogen-inducible gene 3?-hydroxysteroid dehydrogenase/carbonyl reductase (3?-HSD/CR) from Comamonas testosteroni (C. testosteroni) was created as a positive control. Steroid induction could be detected by a microplate fluorescence reader, when the plasmids were transformed into Escherichia coli (E. coli) HB101 cells. With our meta-genomic pKEGFP-2 approach, we identified two estradiol-inducible genes from marine strain H5, which are obviously involved in steroid degradation. Sequencing of the pKEGFP-2 inserts and data base research at NCBI revealed that one gene corresponds to 3-ketosteroid-delta-1-dehydrogenase from several Mycobacterium strains, while the other showed high similarity to carboxylesterase in Sebadella termitidis and Brachyspira murdochii. Both 3-ketosteroid-delta-1-dehydrogenase and carboxylesterase are one of the first enzymes in steroid degradation. In addition, we identified a strain H5 specific DNA sequence of 480bp which allows sensitive PCR detection and quantification of strain H5 bacteria in "unknown" seawater samples. Currently, the exact characterization and systematic classification of the marine steroid degrading bacterial strain H5 is envisaged, which might be used for the bioremediation of steroid contaminations in seawater. Article from a special issue on steroids and microorganisms. PMID:21310233

Sang, Yingying; Xiong, Guangming; Maser, Edmund

2012-03-01

71

THE COLONY OVERLAY PROCEDURE FOR PEPTIDASES TO DETECT AND ENUMERATE TOTAL VIBRIONACEAE IN MOLLUSCAN SHELLFISH AND THEIR GROWING WATERS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Since 1925, molluscan shellfish harvesting has been regulated in the United States based on sanitary surveys of shellfish growing waters. Surveys have relied on the use of coliform standards which have effectively eliminated outbreaks of typhoid fever and other bacterial illnesses. Only the Vibrio...

72

ABC transporters: bacterial exporters.  

PubMed Central

The ABC transporters (also called traffic ATPases) make up a large superfamily of proteins which share a common function and a common ATP-binding domain. ABC transporters are classified into three major groups: bacterial importers (the periplasmic permeases), eukaryotic transporters, and bacterial exporters. We present a comprehensive review of the bacterial ABC exporter group, which currently includes over 40 systems. The bacterial ABC exporter systems are functionally subdivided on the basis of the type of substrate that each translocates. We describe three main groups: protein exporters, peptide exporters, and systems that transport nonprotein substrates. Prototype exporters from each group are described in detail to illustrate our current understanding of this protein family. The prototype systems include the alpha-hemolysin, colicin V, and capsular polysaccharide exporters from Escherichia coli, the protease exporter from Erwinia chrysanthemi, and the glucan exporters from Agrobacterium tumefaciens and Rhizobium meliloti. Phylogenetic analysis of the ATP-binding domains from 29 bacterial ABC exporters indicates that the bacterial ABC exporters can be divided into two primary branches. One branch contains the transport systems where the ATP-binding domain and the membrane-spanning domain are present on the same polypeptide, and the other branch contains the systems where these domains are found on separate polypeptides. Differences in substrate specificity do not correlate with evolutionary relatedness. A complete survey of the known and putative bacterial ABC exporters is included at the end of the review. PMID:8302219

Fath, M J; Kolter, R

1993-01-01

73

Bacterial Sialidase  

NASA Technical Reports Server (NTRS)

Data shows that elevated sialidase in bacterial vaginosis patients correlates to premature births in women. Bacterial sialidase also plays a significant role in the unusual colonization of Pseudomonas aeruginosa in cystic fibrosis patients. Crystals of Salmonella sialidase have been reproduced and are used for studying the inhibitor-enzyme complexes. These inhibitors may also be used to inhibit a trans-sialidase of Trypanosome cruzi, a very similar enzyme to bacterial sialidase, therefore preventing T. cruzi infection, the causitive agent of Chagas' disease. The Center for Macromolecular Crystallography suggests that inhibitors of bacterial sialidases can be used as prophylactic drugs to prevent bacterial infections in these critical cases.

2004-01-01

74

Bacterial lipopolysaccharide increases tyrosine phosphorylation of zonula adherens proteins and opens the paracellular pathway in lung microvascular endothelia through TLR4, TRAF6, and src family kinase activation  

Technology Transfer Automated Retrieval System (TEKTRAN)

Objective: LPS is a key mediator in vascular leak syndromes associated with Gram-negative bacterial infections and opens the pulmonary vascular endothelial paracellular pathway through protein tyrosine kinase (PTK) activation. We asked which PTKs and signaling molecules mediate LPS-induced endothel...

75

Bacterial vaginosis  

Microsoft Academic Search

Bacterial vaginosis, the most prevalent cause of vaginal discharge in the United States, is characterized microbiologically\\u000a by a shift in the vagina away from a lactobacillus-predominant flora and toward a predominantly anaerobic milieu. The cause\\u000a of bacterial vaginosis is unknown, but the epidemiology of the syndrome suggests that it is sexually associated. Bacterial\\u000a vaginosis has been associated with various complications,

Jane R. Schwebke

2000-01-01

76

Bacterial Communities Associated with Porites White Patch Syndrome (PWPS) on Three Western Indian Ocean (WIO) Coral Reefs  

PubMed Central

The scleractinian coral Porites lutea, an important reef-building coral on western Indian Ocean reefs (WIO), is affected by a newly-reported white syndrome (WS) the Porites white patch syndrome (PWPS). Histopathology and culture-independent molecular techniques were used to characterise the microbial communities associated with this emerging disease. Microscopy showed extensive tissue fragmentation generally associated with ovoid basophilic bodies resembling bacterial aggregates. Results of 16S rRNA sequence analysis revealed a high variability between bacterial communities associated with PWPS-infected and healthy tissues in P. lutea, a pattern previously reported in other coral diseases such as black band disease (BBD), white band disease (WBD) and white plague diseases (WPD). Furthermore, substantial variations in bacterial communities were observed at the different sampling locations, suggesting that there is no strong bacterial association in Porites lutea on WIO reefs. Several sequences affiliated with potential pathogens belonging to the Vibrionaceae and Rhodobacteraceae were identified, mainly in PWPS-infected coral tissues. Among them, only two ribotypes affiliated to Shimia marina (NR043300.1) and Vibrio hepatarius (NR025575.1) were consistently found in diseased tissues from the three geographically distant sampling localities. The role of these bacterial species in PWPS needs to be tested experimentally. PMID:24391819

Séré, Mathieu G.; Tortosa, Pablo; Chabanet, Pascale; Turquet, Jean; Quod, Jean-Pascal; Schleyer, Michael H.

2013-01-01

77

Bacterial communities associated with Porites white patch syndrome (PWPS) on three western Indian Ocean (WIO) coral reefs.  

PubMed

The scleractinian coral Porites lutea, an important reef-building coral on western Indian Ocean reefs (WIO), is affected by a newly-reported white syndrome (WS) the Porites white patch syndrome (PWPS). Histopathology and culture-independent molecular techniques were used to characterise the microbial communities associated with this emerging disease. Microscopy showed extensive tissue fragmentation generally associated with ovoid basophilic bodies resembling bacterial aggregates. Results of 16S rRNA sequence analysis revealed a high variability between bacterial communities associated with PWPS-infected and healthy tissues in P. lutea, a pattern previously reported in other coral diseases such as black band disease (BBD), white band disease (WBD) and white plague diseases (WPD). Furthermore, substantial variations in bacterial communities were observed at the different sampling locations, suggesting that there is no strong bacterial association in Porites lutea on WIO reefs. Several sequences affiliated with potential pathogens belonging to the Vibrionaceae and Rhodobacteraceae were identified, mainly in PWPS-infected coral tissues. Among them, only two ribotypes affiliated to Shimia marina (NR043300.1) and Vibrio hepatarius (NR025575.1) were consistently found in diseased tissues from the three geographically distant sampling localities. The role of these bacterial species in PWPS needs to be tested experimentally. PMID:24391819

Séré, Mathieu G; Tortosa, Pablo; Chabanet, Pascale; Turquet, Jean; Quod, Jean-Pascal; Schleyer, Michael H

2013-01-01

78

Bacterial vaginosis  

Microsoft Academic Search

Bacterial vaginosis is the most common cause of vaginitis, affecting over 3 million women in the United States annually. Depopulation of lactobacilli from the normal vaginal flora and overgrowth of Gardnerella vaginalis and other anaerobic species are the presumed etiology. To date, no scientific evidence shows that bacterial vaginosis is a sexually transmitted disease. Malodorous vaginal discharge is the most

Jeff Wang

2000-01-01

79

Expansion of the aminoglycoside-resistance 16S rRNA (m(1)A1408) methyltransferase family: expression and functional characterization of four hypothetical enzymes of diverse bacterial origin.  

PubMed

The global dissemination, potential activity in diverse species and broad resistance spectrum conferred by the aminoglycoside-resistance ribosomal RNA methyltransferases make them a significant potential new threat to the efficacy of aminoglycoside antibiotics in the treatment of serious bacterial infections. The N1 methylation of adenosine 1408 (m(1)A1408) confers resistance to structurally diverse aminoglycosides, including kanamycin, neomycin and apramycin. The limited analyses to date of the enzymes responsible have identified common features but also potential differences in their molecular details of action. Therefore, with the goal of expanding the known 16S rRNA (m(1)A1408) methyltransferase family as a platform for developing a more complete mechanistic understanding, we report here the cloning, expression and functional analyses of four hypothetical aminoglycoside-resistance rRNA methyltransferases from recent genome sequences of diverse bacterial species. Each of the genes produced a soluble, folded protein with a secondary structure, as determined from circular dichroism (CD) spectra, consistent with enzymes for which high-resolution structures are available. For each enzyme, antibiotic minimum inhibitory concentration (MIC) assays revealed a resistance spectrum characteristic of the known 16S rRNA (m(1)A1408) methyltransferases and the modified nucleotide was confirmed by reverse transcription as A1408. In common with other family members, higher binding affinity for the methylation reaction by-product S-adenosylhomocysteine (SAH) than the cosubstrate S-adenosyl-L-methionine (SAM) was observed for three methyltransferases, while one unexpectedly showed no measurable affinity for SAH. Collectively, these results confirm that each hypothetical enzyme is a functional 16S rRNA (m(1)A1408) methyltransferase but also point to further potential mechanistic variation within this enzyme family. PMID:24963996

Witek, Marta A; Conn, Graeme L

2014-09-01

80

Bacterial Vaginosis  

MedlinePLUS

... Archive STDs Home Page Bacterial Vaginosis (BV) Chlamydia Gonorrhea Genital Herpes HIV/AIDS & STDs Human Papillomavirus (HPV) ... of getting other STDs, such as chlamydia and gonorrhea . These bacteria can sometimes cause pelvic inflammatory disease ( ...

81

The Arabidopsis thaliana At4g13040 gene, a unique member of the AP2/EREBP family, is a positive regulator for salicylic acid accumulation and basal defense against bacterial pathogens.  

PubMed

The Arabidopsis genome contains a large number of putative transcription factors, containing a DNA binding domain similar to APETALA2/ethylene response element binding protein (AP2/EREBP), for most of which a function is not known. Phylogenetic analysis divides the Apetala 2 (AP2) super-family into 5 major groups: AP2, RAV, ethylene response factor (ERF), dehydration response element binding protein (DREB) and At4g13040. Similar to ERF and DREB, the At4g13040 protein contains only one AP2 domain; however, its structural uniqueness places it into a distinct group. In this article, we report that At4g13040 (referred herein as Apetala 2 family protein involved in SA mediated disease defense 1 - APD1) is an important regulator for SA mediated plant defense. The APD1 gene is upregulated upon pathogen inoculation, exogenous SA application and in the mutant that constitutively activates SA signaling. The T-DNA insertion lines (inserted in the APD1 promoter), which fail to induce expression upon pathogen inoculation, are compromised for resistance against virulent bacterial pathogens and show reduced induction of pathogenesis related 1 gene. Our results suggest that APD1 functions downstream of PAD4 in Arabidopsis and promotes pathogen-induced SA accumulation. Exogenous SA application completely restores the loss-of-resistance phenotype of the apd1 mutant. Thus, APD1 is a positive regulator of disease defense that functions upstream of SA accumulation. PMID:24612849

Giri, Mrunmay Kumar; Swain, Swadhin; Gautam, Janesh Kumar; Singh, Subaran; Singh, Nidhi; Bhattacharjee, Lipika; Nandi, Ashis Kumar

2014-06-15

82

Bacterial cytotoxins: targeting eukaryotic switches  

Microsoft Academic Search

Many bacterial cytotoxins act on eukaryotic cells by targeting the regulators that are involved in controlling the cytoskeleton or by directly modifying actin, with members of the Rho GTPase family being particularly important targets. The actin cytoskeleton, and especially the GTPase 'molecular switches' that are involved in its control, have crucial functions in innate and adaptive immunity, and have pivotal

Joseph T. Barbieri; Klaus Aktories

2005-01-01

83

Bacterial Wilt  

Microsoft Academic Search

Bacterial wilt is caused by the bacterium Curtobacterium flaccumfaciens subsp. flaccumfaciens. This pathogen grows throughout the water conducting tissues of the plant and impedes water movement, resulting in a wilt. Symptom development is favored by temperatures greater than 90°F. Infection is often caused by the planting of infected seed, but the pathogen may also survive in infested crop debris. Wilt

Howard F. Schwartz; David H. Gent; Gary D. Franc; Robert M. Harveson

84

Bacterial vaginosis  

Microsoft Academic Search

Bacterial vaginosis is the commonest cause of abnormal vaginal discharge in women of childbearing age, with a prevalence as high as 50% in some communities. The symptoms of discharge and offensive smell can cause considerable distress, although 50% of women are asymptomatic when diagnosed. Microbiologically the usually dominant lactobacillus flora is overwhelmed by an overgrowth of predominantly anaerobic organisms, accompanied

Phillip Hay

2010-01-01

85

Bacterial vaginosis  

Microsoft Academic Search

Bacterial vaginosis is a common cause of abnormal discharge in women of child-bearing age. It is present in 10–20% women in the UK, and may recur or regress spontaneously. It is not regarded as an STI because it can occur in virgin women, but it is more common in sexually active women. Other associations include smoking, partner change, having a

Phillip Hay

2005-01-01

86

Bacterial communities associated with healthy and Acropora white syndrome-affected corals from American Samoa  

USGS Publications Warehouse

Acropora white syndrome (AWS) is characterized by rapid tissue loss revealing the white underlying skeleton and affects corals worldwide; however, reports of causal agents are conflicting. Samples were collected from healthy and diseased corals and seawater around American Samoa and bacteria associated with AWS characterized using both culture-dependent and culture-independent methods, from coral mucus and tissue slurries, respectively. Bacterial 16S rRNA gene clone libraries derived from coral tissue were dominated by the Gammaproteobacteria, and Jaccard's distances calculated between the clone libraries showed that those from diseased corals were more similar to each other than to those from healthy corals. 16S rRNA genes from 78 culturable coral mucus isolates also revealed a distinct partitioning of bacterial genera into healthy and diseased corals. Isolates identified as Vibrionaceae were further characterized by multilocus sequence typing, revealing that whilst several Vibrio spp. were found to be associated with AWS lesions, a recently described species, Vibrio owensii, was prevalent amongst cultured Vibrio isolates. Unaffected tissues from corals with AWS had a different microbiota than normal Acropora as found by others. Determining whether a microbial shift occurs prior to disease outbreaks will be a useful avenue of pursuit and could be helpful in detecting prodromal signs of coral disease prior to manifestation of lesions.

Wilson, Bryan; Aeby, Greta S.; Work, Thierry M.; Bourne, David G.

2012-01-01

87

A New Family of Membrane Electron Transporters and Its Substrates, Including a New Cell Envelope Peroxiredoxin, Reveal a Broadened Reductive Capacity of the Oxidative Bacterial Cell Envelope  

PubMed Central

ABSTRACT The Escherichia coli membrane protein DsbD functions as an electron hub that dispatches electrons received from the cytoplasmic thioredoxin system to periplasmic oxidoreductases involved in protein disulfide isomerization, cytochrome c biogenesis, and sulfenic acid reduction. Here, we describe a new class of DsbD proteins, named ScsB, whose members are found in proteobacteria and Chlamydia. ScsB has a domain organization similar to that of DsbD, but its amino-terminal domain differs significantly. In DsbD, this domain directly interacts with substrates to reduce them, which suggests that ScsB acts on a different array of substrates. Using Caulobacter crescentus as a model organism, we searched for the substrates of ScsB. We discovered that ScsB provides electrons to the first peroxide reduction pathway identified in the bacterial cell envelope. The reduction pathway comprises a thioredoxin-like protein, TlpA, and a peroxiredoxin, PprX. We show that PprX is a thiol-dependent peroxidase that efficiently reduces both hydrogen peroxide and organic peroxides. Moreover, we identified two additional proteins that depend on ScsB for reduction, a peroxiredoxin-like protein, PrxL, and a novel protein disulfide isomerase, ScsC. Altogether, our results reveal that the array of proteins involved in reductive pathways in the oxidative cell envelope is significantly broader than was previously thought. Moreover, the identification of a new periplasmic peroxiredoxin indicates that in some bacteria, it is important to directly scavenge peroxides in the cell envelope even before they reach the cytoplasm. PMID:22493033

Cho, Seung-Hyun; Parsonage, Derek; Thurston, Casey; Dutton, Rachel J.; Poole, Leslie B.; Collet, Jean-Francois; Beckwith, Jon

2012-01-01

88

Molecular cloning and characterization of a mouse homolog of bacterial ClpX, a novel mammalian class II member of the Hsp100/Clp chaperone family.  

PubMed

In this paper, we present the molecular cloning and characterization of a murine homolog of the Escherichia coli chaperone ClpX. Murine ClpX shares 38% amino acid sequence identity with the E. coli homolog and is a novel member of the Hsp100/Clp family of molecular chaperones. ClpX localizes to human chromosome 15q22.2-22.3 and in mouse is expressed tissue-specifically as one transcript of approximately 2.9 kilobases (kb) predominantly within the liver and as two isoforms of approximately 2.6 and approximately 2.9 kb within the testes. Purified recombinant ClpX displays intrinsic ATPase activity, with a Km of approximately 25 microM and a Vmax of approximately 660 pmol min-1 microgram-1, which is active over a broad range of pH, temperature, ethanol, and salt parameters. Substitution of lysine 300 with alanine in the ATPase domain P-loop abolishes both ATP hydrolysis and binding. Recombinant ClpX can also interact with its putative partner protease subunit ClpP in overexpression experiments in 293T cells. Subcellular studies by confocal laser scanning microscopy localized murine ClpX green fluorescent protein fusions to the mitochondria. Deletion of the N-terminal mitochondrial targeting sequence abolished mitochondrial compartmentalization. Our results thus suggest that murine ClpX acts as a tissue-specific mammalian mitochondrial chaperone that may play a role in mitochondrial protein homeostasis. PMID:10347188

Santagata, S; Bhattacharyya, D; Wang, F H; Singha, N; Hodtsev, A; Spanopoulou, E

1999-06-01

89

Structural basis for dimerization and catalysis of a novel esterase from the GTSAG motif subfamily of the bacterial hormone-sensitive lipase family.  

PubMed

Hormone-sensitive lipases (HSLs) are widely distributed in microorganisms, plants, and animals. Microbial HSLs are classified into two subfamilies, an unnamed new subfamily and the GDSAG motif subfamily. Due to the lack of structural information, the detailed catalytic mechanism of the new subfamily is not yet clarified. Based on sequence analysis, we propose to name the new subfamily as the GTSAG motif subfamily. We identified a novel HSL esterase E25, a member of the GTSAG motif subfamily, by functional metagenomic screening, and resolved its structure at 2.05 Å. E25 is mesophilic (optimum temperature at 50 °C), salt-tolerant, slightly alkaline (optimum pH at 8.5) for its activity, and capable of hydrolyzing short chain monoesters (C2-C10). E25 tends to form dimers both in the crystal and in solution. An E25 monomer contains an N-terminal CAP domain, and a classical ?/? hydrolase-fold domain. Residues Ser(186), Asp(282), and His(312) comprise the catalytic triad. Structural and mutational analyses indicated that E25 adopts a dimerization pattern distinct from other HSLs. E25 dimer is mainly stabilized by an N-terminal loop intersection from the CAP domains and hydrogen bonds and salt bridges involving seven highly conserved hydrophilic residues from the catalytic domains. Further analysis indicated that E25 also has some catalytic profiles different from other HSLs. Dimerization is essential for E25 to exert its catalytic activity by keeping the accurate orientation of the catalytic Asp(282) within the catalytic triad. Our results reveal the structural basis for dimerization and catalysis of an esterase from the GTSAG motif subfamily of the HSL family. PMID:24867954

Li, Ping-Yi; Ji, Peng; Li, Chun-Yang; Zhang, Yi; Wang, Guang-Long; Zhang, Xi-Ying; Xie, Bin-Bin; Qin, Qi-Long; Chen, Xiu-Lan; Zhou, Bai-Cheng; Zhang, Yu-Zhong

2014-07-01

90

Bacterial Enteritides of Poultry  

Microsoft Academic Search

Enteric bacterial infections in poultry pose a threat to intestinal health and can contribute to poor feed efficiency and livability of a flock. A variety of enteric bacterial diseases are recognized in poultry. Three of these bacterial diseases, necrotic enteritis, ulcerative enteritis, and spirochetosis, primarily infect the intestine, whereas other bacterial diseases, such as salmonellosis, colibacillosis, mycobacteriosis, erysipelas, and fowl

ROBERT E. PORTER

91

Mechanism and specificity of bacterial two-component signaling systems  

E-print Network

Bacterial two component signaling (TCS) systems are the predominant means by which bacteria sense and respond to external signals. These systems represent a large family of paralogous proteins; often hundreds of the histidine ...

Lubin, Emma A. (Emma Alexandra)

2010-01-01

92

Bacterial protein toxins that modify host regulatory GTPases  

Microsoft Academic Search

Many bacterial pathogens produce protein toxins to outmanoeuvre the immune system of the host. Some of these proteins target regulatory GTPases such as those belonging to the RHO family, which control the actin cytoskeleton of the host cell. In this Review, I discuss a diversity of mechanisms that are used by bacterial effectors and toxins to modulate the activity of

Klaus Aktories

2011-01-01

93

Bacterial lipolytic enzymes: classification and properties.  

PubMed Central

Knowledge of bacterial lipolytic enzymes is increasing at a rapid and exciting rate. To obtain an overview of this industrially very important class of enzymes and their characteristics, we have collected and classified the information available from protein and nucleotide databases. Here we propose an updated and extensive classification of bacterial esterases and lipases based mainly on a comparison of their amino acid sequences and some fundamental biological properties. These new insights result in the identification of eight different families with the largest being further divided into six subfamilies. Moreover, the classification enables us to predict (1) important structural features such as residues forming the catalytic site or the presence of disulphide bonds, (2) types of secretion mechanism and requirement for lipase-specific foldases, and (3) the potential relationship to other enzyme families. This work will therefore contribute to a faster identification and to an easier characterization of novel bacterial lipolytic enzymes. PMID:10493927

Arpigny, J L; Jaeger, K E

1999-01-01

94

Bacterial shape: growing off this mortal coil.  

PubMed

Members of the actin-like MreB family of proteins localize as a helical filament in bacteria and are important for determining cylindrical cell shape. Recent results show that new cell wall biosynthesis occurs along a helical track dependent on one of these actin homologs, providing new insights into bacterial cell growth, division and shape. PMID:13678608

Margolin, William

2003-09-16

95

Bacterial Gene Transfer  

NSDL National Science Digital Library

This resource provides detailed instructions for carrying out several laboratory exercises relating to bacterial transformation and conjugation. In this multi-session experiment, students are exposed to various techniques in microbiology, including bacterial transformation and assay and sterile techniques.

Roberta Ellington (Northwestern University; )

1991-01-01

96

Bacterial Vaginosis (BV)  

MedlinePLUS

... NICHD Research Information Clinical Trials Resources and Publications Bacterial Vaginosis (BV): Condition Information Skip sharing on social media links Share this: Page Content What is BV? Bacterial vaginosis, more commonly called BV, is an infection that ...

97

HOST FAMILY PROGRAM Host family: ____________________________________ Family No. _________  

E-print Network

HOST FAMILY PROGRAM Host family: ____________________________________ Family No. _________ Student: 13 January ­ 28 May 2003 THE FAMILY PROVIDES THE STUDENT WITH: 1. Three meals daily all week long. (If a student should arrive home too late for a meal, the family should leave the prepared meal

98

The intrinsic resistome of bacterial pathogens  

PubMed Central

Intrinsically resistant bacteria have emerged as a relevant health problem in the last years. Those bacterial species, several of them with an environmental origin, present naturally low-level susceptibility to several drugs. It has been proposed that intrinsic resistance is mainly the consequence of the impermeability of cellular envelopes, the activity of multidrug efflux pumps or the lack of appropriate targets for a given family of drugs. However, recently published articles indicate that the characteristic phenotype of susceptibility to antibiotics of a given bacterial species depends on the concerted activity of several elements, what has been named as intrinsic resistome. These determinants comprise not just classical resistance genes. Other elements, several of them involved in basic bacterial metabolic processes, are of relevance for the intrinsic resistance of bacterial pathogens. In the present review we analyze recent publications on the intrinsic resistomes of Escherichia coli and Pseudomonas aeruginosa. We present as well information on the role that global regulators of bacterial metabolism, as Crc from P. aeruginosa, may have on modulating bacterial susceptibility to antibiotics. Finally, we discuss the possibility of searching inhibitors of the intrinsic resistome in the aim of improving the activity of drugs currently in use for clinical practice. PMID:23641241

Olivares, Jorge; Bernardini, Alejandra; Garcia-Leon, Guillermo; Corona, Fernando; B. Sanchez, Maria; Martinez, Jose L.

2013-01-01

99

Covariation of viral parameters with bacterial assemblage richness and diversity in the water column and sediments  

NASA Astrophysics Data System (ADS)

Viruses are hypothesized to maintain diversity in microbial assemblages by regulating the abundance of dominant competitors and thereby allowing less-dominant competitors to persist in assemblages; however, there have been few empirical data sets to support this idea. In this study, we examined the relationship between the ratio of viral abundance to bacterial abundance, viral production, and the relative richness and diversity of bacterial assemblage fingerprints, in samples taken from geographically widespread locations (North Pacific gyre, the Amazon River plume and adjacent North Atlantic gyre, Gulf of Mexico, Southern California Bight and Arafura—Coral Seas) which are oligo- to mesotrophic. Bacterial assemblage richness and diversity as measured by automated rRNA intergenic spacer (ARISA) fingerprinting were significantly and positively correlated with the ratio of virus abundance to bacteria abundance (VBR) and to the rate of virus production only in the oligotrophic North Pacific gyre. ARISA fingerprint richness/diversity were not significantly correlated to viral parameters when assessed across all samples in surface waters, suggesting there is not a singular global quantitative relationship between viral pressure and host diversity within well evolved host/virus systems in different geographic locations in plankton. In sediments off Southern California, viral parameters significantly and negatively correlated with ARISA diversity, suggesting strong viral interactions in this habitat. To examine covariation of viral parameters and the relative abundance and diversity of rarer bacterial taxa (i.e., less-dominant competitor), the richness and diversity of diazotroph communities was measured using terminal restriction fragment length polymorphism (TRFLP) of a portion ( nifH) of the nitrogenase gene. The richness and diversity of diazotrophic communities were significantly and negatively correlated with viral parameters across all locations. Since diazotrophs include many opportunistic taxa (e.g. Vibrionaceae), and because these bacteria may be more susceptible to viral attack due to enhanced resource uptake abilities and potentially rapid localized growth, it is possible that this negative effect was due to enhanced viral lysis. Consequently, virus infection may have positive effects upon bacterioplankton diversity in the oligotrophic ocean, by regulating the abundance of dominant competitors, and allowing rarer taxa to coexist; however, some rarer taxa (such as diazotrophs) may be more susceptible to viral attack due to opportunistic lifestyles.

Hewson, Ian; Fuhrman, Jed A.

2007-05-01

100

Facial bacterial infections: folliculitis.  

PubMed

Facial bacterial infections are most commonly caused by infections of the hair follicles. Wherever pilosebaceous units are found folliculitis can occur, with the most frequent bacterial culprit being Staphylococcus aureus. We review different origins of facial folliculitis, distinguishing bacterial forms from other infectious and non-infectious mimickers. We distinguish folliculitis from pseudofolliculitis and perifolliculitis. Clinical features, etiology, pathology, and management options are also discussed. PMID:25441463

Laureano, Ana Cristina; Schwartz, Robert A; Cohen, Philip J

2014-01-01

101

Biodegradability of bacterial surfactants  

Microsoft Academic Search

This work aimed at evaluating the biodegradability of different bacterial surfactants in liquid medium and in soil microcosms.\\u000a The biodegradability of biosurfactants by pure and mixed bacterial cultures was evaluated through CO2 evolution. Three bacterial strains, Acinetobacter baumanni LBBMA ES11, Acinetobacter haemolyticus LBBMA 53 and Pseudomonas sp. LBBMA 101B, used the biosurfactants produced by Bacillus sp. LBBMA 111A (mixed lipopeptide),

Tânia M. S. Lima; Lorena C. Procópio; Felipe D. Brandão; André M. X. Carvalho; Marcos R. Tótola; Arnaldo C. Borges

2011-01-01

102

Bacterial insecticidal toxins.  

PubMed

Over the years it has been important for humans to control the populations of harmful insects and insecticides have been used for this purpose in agricultural and horticultural sectors. Synthetic insecticides, owing to their various side effects, have been widely replaced by biological insecticides. In this review we attempt to describe three bacterial species that are known to produce insecticidal toxins of tremendous biotechnological, agricultural, and economic importance. Bacillus thuringiensis (BT) accounts for 90% of the bioinsecticide market and it produces insecticidal toxins referred to as delta endotoxins. The other two bacteria belong to the genera Photorhabdus and Xenorhabdus, which are symbiotically associated with entomopathogenic nematodes of the families Heterorhabditidae and Steinernematidae respectively. Whereas, Xenorhabdus and Photorhabdus exist in a mutualistic association with the entomopathogenic nematodes, BT act alone. BT formulations are widely used in the field against insects; however, over the years there has been a gradual development of insect resistance against BT toxins. No resistance against Xenorhabdus or Photorhabdus has been reported to date. More recently BT transgenic crops have been prepared; however, there are growing concerns about the safety of these genetically modified crops. Nematodal formulations are also used in the field to curb harmful insect populations. Resistance development to entomopathogenic nematodes is unlikely due to the physical macroscopic nature of infection. Xenorhabdus and Photorhabdus transgenes have not yet been prepared; but are predicted to be available in the near future. In this review we start with an overview of the synthetic insecticides and then discuss Bacillus thuringiensis, Xenorhabdus nematophilus, and Photorhabdus luminescens in greater detail. PMID:15116762

Chattopadhyay, Abanti; Bhatnagar, N B; Bhatnagar, Rakesh

2004-01-01

103

Fungal and Bacterial Diseases.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Fungal and bacterial diseases are important constraints to production. Recognition of diseases and information on their biology is important in disease management. This chapter is aimed at providing diagnostic information on fungal and bacterial diseases of sugar beet and their biology, epidemiolo...

104

7, 787822, 2010 Increased bacterial  

E-print Network

BGD 7, 787­822, 2010 Increased bacterial growth efficiency with environmental variability M if available. Increased bacterial growth efficiency with environmental variability: results from DOC­822, 2010 Increased bacterial growth efficiency with environmental variability M. Eichinger et al. Title

Poggiale, Jean-Christophe

105

Bacterial alginates: from biosynthesis to applications  

Microsoft Academic Search

Alginate is a polysaccharide belonging to the family of linear (unbranched), non-repeating copolymers, consisting of variable amounts \\u0009of ?-d-mannuronic acid and its C5-epimer ?-\\u0009l-guluronic acid linked via ?-1,4-glycosidic bonds. Like DNA, alginate is a negatively charged polymer, imparting material properties ranging from viscous solutions to gel-like structures in the presence of divalent cations. Bacterial alginates are synthesized by only

Uwe Remminghorst; Bernd H. A. Rehm

2006-01-01

106

Contraceptive use in women with bacterial vaginosis  

Microsoft Academic Search

The aim of the study was to investigate if bacterial vaginosis (BV) is associated with use of specific contraceptives. Women at family planning and youth clinics (n = 956), among whom 131 had BV, were subjects for structured in-depth interviews including current and previous contraceptive use. Variables measuring sexual risk-taking were ascertained. Current users of contraceptives were compared with non-users.

Marina Shoubnikova; Dan Hellberg; Staffan Nilsson; Per-Anders Mårdh

1997-01-01

107

The role of cytoskeletal elements in shaping bacterial cells.  

PubMed

Beginning from the recognition of FtsZ as a bacterial tubulin homolog in the early 1990s, many bacterial cytoskeletal elements have been identified, including homologs to the major eukaryotic cytoskeletal elements (tubulin, actin, and intermediate filament) and the elements unique in prokaryotes (ParA/MinD family and bactofilins). The discovery and functional characterization of the bacterial cytoskeleton have revolutionized our understanding of bacterial cells, revealing their elaborate and dynamic subcellular organization. As in eukaryotic systems, the bacterial cytoskeleton participates in cell division, cell morphogenesis, DNA segregation, and other important cellular processes. However, in accordance with the vast difference between bacterial and eukaryotic cells, many bacterial cytoskeletal proteins play distinct roles from their eukaryotic counterparts; for example, control of cell wall synthesis for cell division and morphogenesis. This review is aimed at providing an overview of the bacterial cytoskeleton, and discussing the roles and assembly dynamics of bacterial cytoskeletal proteins in more detail in relation to their most widely conserved functions, DNA segregation and coordination of cell wall synthesis. PMID:25262683

Cho, Hongbaek

2015-03-28

108

Family Secrets  

Microsoft Academic Search

The purpose of this article is to provide an overview of the literature that reveals extensive classifications of the family secrets. The review includes definitions, comparisons of family secrecy to family privacy, types of family secrets, reasons why families avoid exposing certain activities, and factors contributing to the maintenance of a secret. The disclosing of hidden information is discussed with

NAIMA BROWN-SMITH

1998-01-01

109

Family History  

MedlinePLUS

Your family history includes health information about you and your close relatives. Families have many factors in common, including their genes, ... as heart disease, stroke, and cancer. Having a family member with a disease raises your risk, but ...

110

Microfluidics for bacterial chemotaxis  

E-print Network

Bacterial chemotaxis, a remarkable behavioral trait which allows bacteria to sense and respond to chemical gradients in the environment, has implications in a broad range of fields including but not limited to disease ...

Ahmed, Tanvir, Ph. D. Massachusetts Institute of Technology

2011-01-01

111

Bacterial Skin Infections  

MedlinePLUS

... Resources for Help and Information The One-Page Merck Manual of Health Medical Terms Conversion Tables Manuals available ... Lymphangitis Necrotizing Skin Infections Staphylococcal Scalded Skin Syndrome Merck Manual > Patients & Caregivers > Skin Disorders > Bacterial Skin Infections 4 ...

112

Small bowel bacterial overgrowth  

MedlinePLUS

Overgrowth - intestinal bacteria; Bacterial overgrowth - intestine ... Unlike the large intestine, the small intestine does not have a high number of bacteria. When there are too many bacteria in the ...

113

Family Privilege  

ERIC Educational Resources Information Center

Family privilege is defined as "strengths and supports gained through primary caring relationships." A generation ago, the typical family included two parents and a bevy of kids living under one roof. Now, every variation of blended caregiving qualifies as family. But over the long arc of human history, a real family was a…

Seita, John R.

2014-01-01

114

Bacterial growth with chlorinated methanes.  

PubMed Central

Chlorinated methanes are important industrial chemicals and significant environmental pollutants. While the highly chlorinated methanes, trichloromethane and tetrachloromethane, are not productively metabolized by bacteria, chloromethane and dichloromethane are used by both aerobic and anaerobic methylotrophic bacteria as carbon and energy sources. Some of the dehalogenation reactions involved in the utilization of the latter two compounds have been elucidated. In a strictly anaerobic acetogenic bacterium growing with chloromethane, an inducible enzyme forming methyltetrahydrofolate and chloride from chloromethane and tetrahydrofolate catalyzes dehalogenation of the growth substrate. A different mechanism for the nucleophilic displacement of chloride is observed in aerobic methylotrophic bacteria utilizing dichloromethane as the sole carbon and energy source. These organisms possess the enzyme dichloromethane dehalogenase which, in a glutathione-dependent reaction, converts dichloromethane to inorganic chloride and formaldehyde, a central metabolite of methylotrophic growth. Sequence comparisons have shown that bacterial dichloromethane dehalogenases belong to the glutathione S-transferase enzyme family, and within this family to class Theta. The dehalogenation reactions underlying aerobic utilization of chloromethane by a pure culture and anaerobic growth with dichloromethane by an acetogenic mixed culture are not known. It appears that they are based on mechanisms other than nucleophilic attack by tetrahydrofolate or glutathione. PMID:8565906

Leisinger, T; Braus-Stromeyer, S A

1995-01-01

115

Family Secrets and Family Environment  

Microsoft Academic Search

This study explored whether family secrecy might be a potential mediator of later adult psychological functioning in the offspring of the family. Results revealed that family secrecy was related to psychological well-being in adulthood. The number of potentially secretive events, as well as the negativity of the family environment were strongly associated with poorer psychological functioning.

Marianne F. Jahn

1995-01-01

116

Tracking bacterial growth in liquid media and a new bacterial life model  

Microsoft Academic Search

By increasing viscosity of liquid media above 8.4 centipoise (cp) i.e. 0.084 g· cm-1 · s-1, individual growth and family formation ofEscherichia coli was continuously observed in real-time for up to 6 h. The observations showed primarily unidirectional growth and reproduction\\u000a ofE. coli and suggested more than one reproduction in the observed portion ofE. coli life span. A new bacterial

Shi Liu

1999-01-01

117

Crystal Structures of Cif from Bacterial Pathogens Photorhabdus luminescens and Burkholderia pseudomallei  

Microsoft Academic Search

A pre-requisite for bacterial pathogenesis is the successful interaction of a pathogen with a host. One mechanism used by a broad range of Gram negative bacterial pathogens is to deliver effector proteins directly into host cells through a dedicated type III secretion system where they modulate host cell function. The cycle inhibiting factor (Cif) family of effector proteins, identified in

Allister Crow; Paul R. Race; Grégory Jubelin; Carolina Varela Chavez; Jean-Michel Escoubas; Eric Oswald; Mark J. Banfield; Bostjan Kobe

2009-01-01

118

Proteomics of bacterial pathogens.  

PubMed

The rapid growth of proteomics that has been built upon the available bacterial genome sequences has opened provided new approaches to the analysis of bacterial functional genomics. In the study of pathogenic bacteria the combined technologies of genomics, proteomics and bioinformatics has provided valuable tools for the study of complex phenomena determined by the action of multiple gene sets. The review considers some of the recent developments in the establishment of proteomic databases as well as attempts to define pathogenic determinants at the level of the proteome for some of the major human pathogens. Proteomics can also provide practical applications through the identification of immunogenic proteins that may be potential vaccine targets as well as in extending our understanding of antibiotic action. There is little doubt that proteomics has provided us with new and valuable information on bacterial pathogens and will continue to be an important source of information in the coming years. PMID:12934927

Cash, Phillip

2003-01-01

119

An algebraic view of bacterial genome evolution.  

PubMed

Rearrangements of bacterial chromosomes can be studied mathematically at several levels, most prominently at a local, or sequence level, as well as at a topological level. The biological changes involved locally are inversions, deletions, and transpositions, while topologically they are knotting and catenation. These two modelling approaches share some surprising algebraic features related to braid groups and Coxeter groups. The structural approach that is at the core of algebra has long found applications in sciences such as physics and analytical chemistry, but only in a small number of ways so far in biology. And yet there are examples where an algebraic viewpoint may capture a deeper structure behind biological phenomena. This article discusses a family of biological problems in bacterial genome evolution for which this may be the case, and raises the prospect that the tools developed by algebraists over the last century might provide insight to this area of evolutionary biology. PMID:24375264

Francis, Andrew R

2014-12-01

120

Emerging bacterial enzyme targets.  

PubMed

The treatment of bacterial infections is increasingly complicated by the ability of bacteria to develop resistance to antimicrobial agents, as well as by the emergence of new pathogens with the potential for rapid global spread. Thus, there is a critical need for novel antibacterial agents and new strategies to advance the drug discovery process. In the post-genomic era, comparative genomics, functional genomics and proteomics will play important roles in identifying new enzyme targets for the discovery of novel antibacterial agents. This review will discuss bacterial enzyme targets, specifically focusing on enzymes involved in fatty acid and cell wall biosynthesis. PMID:17328230

Su, Zhengding; Honek, John F

2007-02-01

121

Family History  

MedlinePLUS

... Home CDC 24/7: Saving Lives. Protecting People.™ Genomics All CDC Topics Search The CDC Note: Javascript ... visit this page: About CDC.gov . Public Health Genomics Genomics Family Health History Share Compartir Family History ...

122

Family Arguments  

MedlinePLUS

... Pediatric First Aid for Caregivers and Teachers (PedFACTs) Teaching Package HealthyChildren.org Post-it Notes Family Life Health Management - Medical Home Family Dynamics Adoption & Foster Care Communication & Discipline Types ...

123

Family Meals  

MedlinePLUS

... Sports: Keeping Kids Safe Concussions: What to Know Family Meals KidsHealth > Parents > Nutrition & Fitness Center > Healthy Eating & ... even more important as kids get older. Making Family Meals Happen It can be a big challenge ...

124

Foster Families  

MedlinePLUS

... child in another home. Continue Why Do Kids Live With Foster Families? Most often, a kid goes ... this stressful and emotional time. Why Do Kids Live With Foster Families? Most often, a kid goes ...

125

Bacterial mortality and the fate of bacterial production  

Microsoft Academic Search

Knowledge of the rates of bacterial mortality, particularly predatory mortality, is important in determining the fate of bacterial\\u000a production. Communities of planktonic bacteria have specific growth rates on the order of 1 d?1, but there is relatively little variation in bacterial abundance, implying that growth and mortality are closely coupled.\\u000a A review of the mechanisms of bacterial mortality suggests that

Michael L. Pace; Mary Flagler Cary Arboretum

1988-01-01

126

Bacterial Microcompartment Organelles: Protein Shell Structure and Evolution  

PubMed Central

Some bacteria contain organelles or microcompartments consisting of a large virion-like protein shell encapsulating sequentially acting enzymes. These organized microcompartments serve to enhance or protect key metabolic pathways inside the cell. The variety of bacterial microcompartments provide diverse metabolic functions, ranging from CO2 fixation to the degradation of small organic molecules. Yet they share an evolutionarily related shell, which is defined by a conserved protein domain that is widely distributed across the bacterial kingdom. Structural studies on a number of these bacterial microcompartment shell proteins are illuminating the architecture of the shell and highlighting its critical role in controlling molecular transport into and out of microcompartments. Current structural, evolutionary, and mechanistic ideas are discussed, along with genomic studies for exploring the function and diversity of this family of bacterial organelles. PMID:20192762

Yeates, Todd O.; Crowley, Christopher S.; Tanaka, Shiho

2012-01-01

127

Family Support.  

ERIC Educational Resources Information Center

This "Feature Issue" of the quarterly journal "Impact" presents 19 brief articles on family support systems in the United States for persons with developmental disabilities and their families. Emphasis is on provisions of Public Law 99-457. Articles include: "Family Support in the United States: Setting a Course for the 1990s" (James Knoll);…

Wieck, Colleen, Ed.; McBride, Marijo, Ed.

1990-01-01

128

Family therapy.  

PubMed

Another major force not letting us succeed in the treatment of diabetes remains right inside the patients home, their family members. Hence, it is important to know the perception of the close family members about this simple and strong tool in diabetes, 'insulin'. The drug is nearing its century, it has not fully being accepted gracefully even in todays electronic savvy society. So, we need to strongly discover the reason for its non-acceptance, while trials are out inventing new drugs. One vital thing that can change this attitude is increasing the understanding of this drug, insulin in depth to close people around the patient, the 'family'. Underestimating family's perception about disease and treatment for diabetes is detrimental to both diseased and the doctor. This consists of a biopsychosocial model; biological, psychological and social factors. Family forms the most important part of it. The strategies in family therapy include psychodynamic, structural, strategic, and cognitive-behavioral component. Diabetes has and will continue to rise, so will be the treatment options. From the clinicians side its to fix fasting first but from patients its fix family first. Family therapy demonstrates the importance of insulin initiation and maintenance in insulin naive patients, and continuation for others. The specific needs of such patients and their impact on family life are met with family therapy. Who needs family therapy? Benefits of family therapy and a case based approach is covered. PMID:24251191

Altamash, Shaikh

2013-10-01

129

Family grief  

Microsoft Academic Search

Grief traditionally has been described from the individual perspective. In contrast, this article presents a family systems perspective on death and grieving. A group of interconnected individuals forming a system, defined as a “family,” reciprocally affect one another in response to internal or external events. Minuchin's structural theory emphasizes the importance of subsystems within a family; boundaries between subsystems are

Carol Michler Detmer; Joseph W. Lamberti

1991-01-01

130

Recent microbiological shifts in perianal bacterial dermatitis: Staphylococcus aureus predominance.  

PubMed

Traditionally, bacterial infections of the anal skin have been found to be caused by Streptococcus. The aim of this study was to determine the breakdown of bacterial isolates and the current presentation of bacterial diseases involving the perineum. From the chart review of children who had bacterial cultures of the anus from 2005 to 2008 in a pediatric dermatology practice population in New York City, 26 pediatric patients (ages 5 months to 12 yrs) who had the indications of anal erythema or recurrent buttocks dermatitis were identified. Bacterial cultures of 17 patients grew pathogens, that of 14 (82% of identifiably infected patients) grew Staphylococcus aureus, in 11 as a solo pathogen (6 MSSA and 5 MRSA in 2 family clusters). Streptococcus was identified in three patients, two on culture and one on latex agglutination test; and two patients were identified as having both group A beta hemolytic Streptococcus and Staphylococcus aureus (2 MSSA and 1 MRSA). In patients with S. aureus perianally, concurrent small papules and pustules of the buttocks or extension of the erythema to adjacent buttock skin was the primary clinical feature distinguishing this condition from isolated streptococcal disease. Whereas Streptococcal infections of the anus and buttocks occur commonly, Staphylococcus aureus has become the leading cause of anal bacterial infection in the setting of skin involvement; therefore, antibacterial therapy for anal and buttock bacterial infections should be tailored accordingly. PMID:20199443

Heath, Candrice; Desai, Nina; Silverberg, Nanette B

2009-01-01

131

The Bacterial Growth Curve.  

ERIC Educational Resources Information Center

A procedure that allows students to view an entire bacterial growth curve during a two- to three-hour student laboratory period is described. Observations of the lag phase, logarithmic phase, maximum stationary phase, and phase of decline are possible. A nonpathogenic, marine bacterium is used in the investigation. (KR)

Paulton, Richard J. L.

1991-01-01

132

Bacterial infections: uncommon presentations  

Microsoft Academic Search

The essence of dermatology is morphology. The most important instrument in the practice of dermatology has always been, and still is, the naked eye; however, “We see only what we are ready to see, what we have been taught to see” (Jean Martin Charcot). Although most practitioners will easily correctly diagnose common bacterial skin diseases (such as cellulitis, erysipelas, impetigo,

Hagit Matz; Edith Orion; Ronni Wolf

2005-01-01

133

Bacterial leaf spot  

Technology Transfer Automated Retrieval System (TEKTRAN)

Bacterial leaf spot has been reported in Australia (Queensland), Egypt, El Salvador, India, Japan, Nicaragua, Sudan, and the United States (Florida, Iowa, Kansas, Maryland, and Wisconsin). It occasionally causes locally severe defoliation and post-emergence damping-off and stunting. The disease is...

134

Bacterial extracellular lignin peroxidase  

DOEpatents

A newly discovered lignin peroxidase enzyme is provided. The enzyme is obtained from a bacterial source and is capable of degrading the lignin portion of lignocellulose in the presence of hydrogen peroxide. The enzyme is extracellular, oxidative, inducible by lignin, larch wood xylan, or related substrates and capable of attacking certain lignin substructure chemical bonds that are not degradable by fungal lignin peroxidases.

Crawford, Donald L. (Moscow, ID); Ramachandra, Muralidhara (Moscow, ID)

1993-01-01

135

BACTERIAL KIDNEY DISEASE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Bacterial kidney disease (BKD), caused by Renibacterium salmoninarum, is a prevalent disease that impacts the sustainable production of salmonid fish for consumption and species conservation efforts. The disease is chronic in nature and mortality most often occurs in 6–12 month old juvenile salmonid...

136

Bacterial microflora of nectarines  

Technology Transfer Automated Retrieval System (TEKTRAN)

Microflora of fruit surfaces has been the best source of antagonists against fungi causing postharvest decays of fruit. However, there is little information on microflora colonizing surfaces of fruits other than grapes, apples, and citrus fruit. We characterized bacterial microflora on nectarine f...

137

BACTERIAL WATERBORNE PATHOGENS  

EPA Science Inventory

Bacterial pathogens are examples of classical etiological agents of waterborne disease. While these agents no longer serve as major threats to U.S. water supplies, they are still important pathogens in areas with substandard sanitation and poor water treatment facilities. In th...

138

Managing recurrent bacterial vaginosis  

Microsoft Academic Search

Bacterial vaginosis (BV) is the most frequently found condition of the female genital tract. It increases a woman’s risk of acquiring HIV, is associated with increased complications in pregnancy, and may be involved in the pathogenesis of pelvic inflammatory disease. Yet there are many unanswered questions about its aetiology, making management of recurrent infection difficult and often idiosyncratic. This paper

J Wilson

2004-01-01

139

ACTIVE BACTERIAL CORE SURVEILLANCE (ABCS)  

EPA Science Inventory

Active Bacterial Core Surveillance is population based surveillance system. Surveillance of invasive bacterial diseases due to pathogens at nine Emerging Infections Program sites. The coverage is the based on a study population, nationwide....

140

Corticosteroids for Bacterial Keratitis  

PubMed Central

Objective To determine whether there is a benefit in clinical outcomes with the use of topical corticosteroids as adjunctive therapy in the treatment of bacterial corneal ulcers. Methods Randomized, placebo-controlled, double-masked, multicenter clinical trial comparing prednisolone sodium phosphate, 1.0%, to placebo as adjunctive therapy for the treatment of bacterial corneal ulcers. Eligible patients had a culture-positive bacterial corneal ulcer and received topical moxifloxacin for at least 48 hours before randomization. Main Outcome Measures The primary outcome was best spectacle-corrected visual acuity (BSCVA) at 3 months from enrollment. Secondary outcomes included infiltrate/scar size, reepithelialization, and corneal perforation. Results Between September 1, 2006, and February 22, 2010, 1769 patients were screened for the trial and 500 patients were enrolled. No significant difference was observed in the 3-month BSCVA (?0.009 logarithm of the minimum angle of resolution [logMAR]; 95% CI, ?0.085 to 0.068; P = .82), infiltrate/scar size (P = .40), time to reepithelialization (P = .44), or corneal perforation (P > .99). A significant effect of corticosteroids was observed in subgroups of baseline BSCVA (P = .03) and ulcer location (P = .04). At 3 months, patients with vision of counting fingers or worse at baseline had 0.17 logMAR better visual acuity with corticosteroids (95% CI, ?0.31 to ?0.02; P = .03) compared with placebo, and patients with ulcers that were completely central at baseline had 0.20 logMAR better visual acuity with corticosteroids (?0.37 to ?0.04; P = .02). Conclusions We found no overall difference in 3-month BSCVA and no safety concerns with adjunctive corticosteroid therapy for bacterial corneal ulcers. Application to Clinical Practice Adjunctive topical corticosteroid use does not improve 3-month vision in patients with bacterial corneal ulcers. PMID:21987582

Srinivasan, Muthiah; Mascarenhas, Jeena; Rajaraman, Revathi; Ravindran, Meenakshi; Lalitha, Prajna; Glidden, David V.; Ray, Kathryn J.; Hong, Kevin C.; Oldenburg, Catherine E.; Lee, Salena M.; Zegans, Michael E.; McLeod, Stephen D.; Lietman, Thomas M.; Acharya, Nisha R.

2013-01-01

141

4, 37993828, 2007 Bacterial production  

E-print Network

limiting bacterial growth was investigated along vertical and longitudinal gradients across the SouthBGD 4, 3799­3828, 2007 Bacterial production limitation in the South Pacific Gyre F. Van Wambeke et forum of Biogeosciences Factors limiting heterotrophic bacterial production in the southern Pacific

Boyer, Edmond

142

Bacterial Respiratory Diseases of Poultry  

Microsoft Academic Search

Bacterial pathogens play an important role in causing respiratory disease in domestic poultry species. In many cases, the bacterial component of a respiratory disease colonizes the respiratory system only after a primary viral or environmental insult. Coloniza- tion of the airsacs of a chicken by Escherichia coli following an infectious bronchitis virus infection is an example of secondary bacterial invasion.

JOHN R. GLISSON

143

Crystal Structures of Two Bacterial 3-Hydroxy-3-methylglutaryl-CoA Lyases Suggest a Common Catalytic Mechanism among a Family of TIM Barrel Metalloenzymes Cleaving Carbon-Carbon Bonds  

SciTech Connect

The enzyme 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) lyase catalyzes the terminal steps in ketone body generation and leucine degradation. Mutations in this enzyme cause a human autosomal recessive disorder called primary metabolic aciduria, which typically kills victims because of an inability to tolerate hypoglycemia. Here we present crystal structures of the HMG-CoA lyases from Bacillus subtilis and Brucella melitensis at 2.7 and 2.3 {angstrom} resolution, respectively. These enzymes share greater than 45% sequence identity with the human orthologue. Although the enzyme has the anticipated triose-phosphate isomerase (TIM) barrel fold, the catalytic center contains a divalent cation-binding site formed by a cluster of invariant residues that cap the core of the barrel, contrary to the predictions of homology models. Surprisingly, the residues forming this cation-binding site and most of their interaction partners are shared with three other TIM barrel enzymes that catalyze diverse carbon-carbon bond cleavage reactions believed to proceed through enolate intermediates (4-hydroxy-2-ketovalerate aldolase, 2-isopropylmalate synthase, and transcarboxylase 5S). We propose the name 'DRE-TIM metallolyases' for this newly identified enzyme family likely to employ a common catalytic reaction mechanism involving an invariant Asp-Arg-Glu (DRE) triplet. The Asp ligates the divalent cation, while the Arg probably stabilizes charge accumulation in the enolate intermediate, and the Glu maintains the precise structural alignment of the Asp and Arg. We propose a detailed model for the catalytic reaction mechanism of HMG-CoA lyase based on the examination of previously reported product complexes of other DRE-TIM metallolyases and induced fit substrate docking studies conducted using the crystal structure of human HMG-CoA lyase (reported in the accompanying paper by Fu, et al. (2006) J. Biol. Chem. 281, 7526-7532). Our model is consistent with extensive mutagenesis results and can guide subsequent studies directed at definitive experimental elucidation of this enzyme's reaction mechanism.

Forouhar,F.; Hussain, M.; Farid, R.; Benach, J.; Abashidze, M.; Edstrom, W.; Vorobiev, S.; Montelione, G.; Hunt, J.; et al.

2006-01-01

144

Positively regulated bacterial expression systems.  

PubMed

Regulated promoters are useful tools for many aspects related to recombinant gene expression in bacteria, including for high-level expression of heterologous proteins and for expression at physiological levels in metabolic engineering applications. In general, it is common to express the genes of interest from an inducible promoter controlled either by a positive regulator or by a repressor protein. In this review, we discuss established and potentially useful positively regulated bacterial promoter systems, with a particular emphasis on those that are controlled by the AraC-XylS family of transcriptional activators. The systems function in a wide range of microorganisms, including enterobacteria, soil bacteria, lactic bacteria and streptomycetes. The available systems that have been applied to express heterologous genes are regulated either by sugars (L-arabinose, L-rhamnose, xylose and sucrose), substituted benzenes, cyclohexanone-related compounds, ?-caprolactam, propionate, thiostrepton, alkanes or peptides. It is of applied interest that some of the inducers require the presence of transport systems, some are more prone than others to become metabolized by the host and some have been applied mainly in one or a limited number of species. Based on bioinformatics analyses, the AraC-XylS family of regulators contains a large number of different members (currently over 300), but only a small fraction of these, the XylS/Pm, AraC/P(BAD), RhaR-RhaS/rhaBAD, NitR/PnitA and ChnR/Pb regulator/promoter systems, have so far been explored for biotechnological applications. PMID:21261879

Brautaset, Trygve; Lale, Rahmi; Valla, Svein

2009-01-01

145

Positively regulated bacterial expression systems  

PubMed Central

Summary Regulated promoters are useful tools for many aspects related to recombinant gene expression in bacteria, including for high?level expression of heterologous proteins and for expression at physiological levels in metabolic engineering applications. In general, it is common to express the genes of interest from an inducible promoter controlled either by a positive regulator or by a repressor protein. In this review, we discuss established and potentially useful positively regulated bacterial promoter systems, with a particular emphasis on those that are controlled by the AraC?XylS family of transcriptional activators. The systems function in a wide range of microorganisms, including enterobacteria, soil bacteria, lactic bacteria and streptomycetes. The available systems that have been applied to express heterologous genes are regulated either by sugars (l?arabinose, l?rhamnose, xylose and sucrose), substituted benzenes, cyclohexanone?related compounds, ??caprolactam, propionate, thiostrepton, alkanes or peptides. It is of applied interest that some of the inducers require the presence of transport systems, some are more prone than others to become metabolized by the host and some have been applied mainly in one or a limited number of species. Based on bioinformatics analyses, the AraC?XylS family of regulators contains a large number of different members (currently over 300), but only a small fraction of these, the XylS/Pm, AraC/PBAD, RhaR?RhaS/rhaBAD, NitR/PnitA and ChnR/Pb regulator/promoter systems, have so far been explored for biotechnological applications. PMID:21261879

Brautaset, Trygve; Lale, Rahmi; Valla, Svein

2009-01-01

146

Bacterial respiratory disease of poultry.  

PubMed

Bacterial pathogens play an important role in causing respiratory disease in domestic poultry species. In many cases, the bacterial component of a respiratory disease colonizes the respiratory system only after a primary viral or environmental insult. Colonization of the airsacs of a chicken by Escherichia coli following an infectious bronchitis virus infection is an example of secondary bacterial invasion. In other cases, the bacterial component of the respiratory disease is the primary initiating cause of the disease. Examples of primary bacterial respiratory disease are infectious coryza in chickens and fowl cholera in chickens and turkeys. PMID:9706078

Glisson, J R

1998-08-01

147

Electrostatic analysis of bacterial expansins.  

PubMed

Expansins are a family of proteins with plant cell wall remodeling-activity, which bind cell wall components through hydrophobic and electrostatic interactions. A shallow area on the surface of the protein serves as the polysaccharide binding site (PBS) and it is composed of conserved residues. However, electric charge differences on the opposite face of the PBS produce basic, neutral, or acidic proteins. An analysis of forty-four bacterial expansins, homologues of BsEXLX1, revealed two main groups defined by: (a) the presence or absence of disulfide bonds; and (b) by the proteins isoelectric point (pI). We determined the location of the residues responsible for the pI on the structure of representative expansins. Our results suggest that the electric charge at the opposite site of the PBS may help in substrate differentiation among expansins from different species; in addition, electrostatic polarization between the front and the back of the molecule could affect expansin activity on cellulose. PMID:25388639

Pastor, Nina; Dávila, Sonia; Pérez-Rueda, Ernesto; Segovia, Lorenzo; Martínez-Anaya, Claudia

2015-02-01

148

Modelling bacterial flagellar growth  

E-print Network

The growth of bacterial flagellar filaments is a self-assembly process where flagellin molecules are transported through the narrow core of the flagellum and are added at the distal end. To model this situation, we generalize a growth process based on the TASEP model by allowing particles to move both forward and backward on the lattice. The bias in the forward and backward jump rates determines the lattice tip speed, which we analyze and also compare to simulations. For positive bias, the system is in a non-equilibrium steady state and exhibits boundary-induced phase transitions. The tip speed is constant. In the no-bias case we find that the length of the lattice grows as $N(t)\\propto\\sqrt{t}$, whereas for negative drift $N(t)\\propto\\ln{t}$. The latter result agrees with experimental data of bacterial flagellar growth.

Schmitt, Maximilian; 10.1209/0295-5075/96/28001

2012-01-01

149

Physics of Bacterial Morphogenesis  

PubMed Central

Summary: Bacterial cells utilize three-dimensional (3D) protein assemblies to perform important cellular functions such as growth, division, chemoreception, and motility. These assemblies are composed of mechanoproteins that can mechanically deform and exert force. Sometimes, small-nucleotide hydrolysis is coupled to mechanical deformations. In this review, we describe the general principle for an understanding of the coupling of mechanics with chemistry in mechanochemical systems. We apply this principle to understand bacterial cell shape and morphogenesis and how mechanical forces can influence peptidoglycan cell wall growth. We review a model that can potentially reconcile the growth dynamics of the cell wall with the role of cytoskeletal proteins such as MreB and crescentin. We also review the application of mechanochemical principles to understand the assembly and constriction of the FtsZ ring. A number of potential mechanisms are proposed, and important questions are discussed. PMID:22126993

Sun, Sean X.; Jiang, Hongyuan

2011-01-01

150

[Bacterial diseases of rape].  

PubMed

Bacterial destruction of the culture was described and its agents identified in the spring and winter rape crops. Typical symptoms are the following: browning of stem tissue and its mucilagization, chlorosis of leaves, yellowing and beginning of soft rot in the place of leaf stalks affixion to stems, loss of pigmentation (violet). Pathogenic properties of the collection strains and morphological, cultural, physiological, and biochemical properties of the agents of rape's bacterial diseases isolated by the authors have been investigated. It was found that all the isolates selected by the authors are highly or moderately aggressive towards different varieties of rape. According to the complex of phenotypic properties 44% of the total number of isolates selected by the authors are related to representatives of the genus Pseudomonas, 37% - to Xanthomonas and 19% - to Pectobacterium. PMID:23293826

Zakharova, O M; Mel'nychuk, M D; Dankevych, L A; Patyka, V P

2012-01-01

151

Bacterial ratchet motors  

PubMed Central

Self-propelling bacteria are a nanotechnology dream. These unicellular organisms are not just capable of living and reproducing, but they can swim very efficiently, sense the environment, and look for food, all packaged in a body measuring a few microns. Before such perfect machines can be artificially assembled, researchers are beginning to explore new ways to harness bacteria as propelling units for microdevices. Proposed strategies require the careful task of aligning and binding bacterial cells on synthetic surfaces in order to have them work cooperatively. Here we show that asymmetric environments can produce a spontaneous and unidirectional rotation of nanofabricated objects immersed in an active bacterial bath. The propulsion mechanism is provided by the self-assembly of motile Escherichia coli cells along the rotor boundaries. Our results highlight the technological implications of active matter’s ability to overcome the restrictions imposed by the second law of thermodynamics on equilibrium passive fluids. PMID:20457936

Di Leonardo, R.; Angelani, L.; Dell’Arciprete, D.; Ruocco, G.; Iebba, V.; Schippa, S.; Conte, M. P.; Mecarini, F.; De Angelis, F.; Di Fabrizio, E.

2010-01-01

152

Bacterial Cell Wall Components  

NASA Astrophysics Data System (ADS)

Bacterial cell-surface polysaccharides cells are surrounded by a variety of cell-surface structures that allow them to thrive in extreme environments. Components of the cell envelope and extracellular matrix are responsible for providing the cells with structural support, mediating intercellular communication, allowing the cells to move or to adhere to surfaces, protecting the cells from attack by antibiotics or the immune system, and facilitating the uptake of nutrients. Some of the most important cell wall components are polysaccharide structures. This review discusses the occurrence, structure, function, and biosynthesis of the most prevalent bacterial cell surface polysaccharides: peptidoglycan, lipopolysaccharide, arabinogalactan, and lipoarabinomannan, and capsular and extracellular polysaccharides. The roles of these polysaccharides in medicine, both as drug targets and as therapeutic agents, are also described.

Ginsberg, Cynthia; Brown, Stephanie; Walker, Suzanne

153

Bacterial Genome Instability  

PubMed Central

SUMMARY Bacterial genomes are remarkably stable from one generation to the next but are plastic on an evolutionary time scale, substantially shaped by horizontal gene transfer, genome rearrangement, and the activities of mobile DNA elements. This implies the existence of a delicate balance between the maintenance of genome stability and the tolerance of genome instability. In this review, we describe the specialized genetic elements and the endogenous processes that contribute to genome instability. We then discuss the consequences of genome instability at the physiological level, where cells have harnessed instability to mediate phase and antigenic variation, and at the evolutionary level, where horizontal gene transfer has played an important role. Indeed, this ability to share DNA sequences has played a major part in the evolution of life on Earth. The evolutionary plasticity of bacterial genomes, coupled with the vast numbers of bacteria on the planet, substantially limits our ability to control disease. PMID:24600039

Darmon, Elise

2014-01-01

154

Bacterial multidrug efflux transporters.  

PubMed

Infections caused by bacteria are a leading cause of death worldwide. Although antibiotics remain a key clinical therapy, their effectiveness has been severely compromised by the development of drug resistance in bacterial pathogens. Multidrug efflux transporters--a common and powerful resistance mechanism--are capable of extruding a number of structurally unrelated antimicrobials from the bacterial cell, including antibiotics and toxic heavy metal ions, facilitating their survival in noxious environments. Transporters of the resistance-nodulation-cell division (RND) superfamily typically assemble as tripartite efflux complexes spanning the inner and outer membranes of the cell envelope. In Escherichia coli, the CusCFBA complex, which mediates resistance to copper(I) and silver(I) ions, is the only known RND transporter specific to heavy metals. Here, we describe the current knowledge of individual pump components of the Cus system, a paradigm for efflux machinery, and speculate on how RND pumps assemble to fight diverse antimicrobials. PMID:24702006

Delmar, Jared A; Su, Chih-Chia; Yu, Edward W

2014-01-01

155

A bacterial ratchet motor  

E-print Network

Self-propelling bacteria are a dream of nano-technology. These unicellular organisms are not just capable of living and reproducing, but they can swim very efficiently, sense the environment and look for food, all packaged in a body measuring a few microns. Before such perfect machines could be artificially assembled, researchers are beginning to explore new ways to harness bacteria as propelling units for micro-devices. Proposed strategies require the careful task of aligning and binding bacterial cells on synthetic surfaces in order to have them work cooperatively. Here we show that asymmetric micro-gears can spontaneously rotate when immersed in an active bacterial bath. The propulsion mechanism is provided by the self assembly of motile Escherichia coli cells along the saw-toothed boundaries of a nano-fabricated rotor. Our results highlight the technological implications of active matter's ability to overcome the restrictions imposed by the second law of thermodynamics on equilibrium passive fluids.

R. Di Leonardo; L. Angelani; G. Ruocco; V. Iebba; M. P. Conte; S. Schippa; F. De Angelis; F. Mecarini; E. Di Fabrizio

2009-10-15

156

Bacterial transformation of terpenoids  

NASA Astrophysics Data System (ADS)

Data on the bacterial transformation of terpenoids published in the literature in the past decade are analyzed. Possible pathways for chemo-, regio- and stereoselective modifications of terpenoids are discussed. Considerable attention is given to new technological approaches to the synthesis of terpenoid derivatives suitable for the use in the perfume and food industry and promising as drugs and chiral intermediates for fine organic synthesis. The bibliography includes 246 references.

Grishko, V. V.; Nogovitsina, Y. M.; Ivshina, I. B.

2014-04-01

157

Acute Bacterial Prostatitis  

Microsoft Academic Search

\\u000a Acute bacterial prostatitis (NIH category I) is diagnosed clinically and from urine culture. It can be a serious infection,\\u000a usually caused by uropathogens, with intense local pain, fever and other systemic symptoms. Prostatic massage is contrain-dicated,\\u000a microbiological diagnosis is usually performed by the midstream urine.\\u000a \\u000a \\u000a Antimicrobial therapy is the most essential part of the therapeutic regimen. Treatment varies according to

Kurt G. Naber; Florian M. E. Wagenlehner; Wolfgang Weidner

158

Recurrent bacterial vaginosis  

Microsoft Academic Search

Bacterial vaginosis (BV) is a common cause of vaginal discharge in women of childbearing age. In some individuals, it recurs\\u000a frequently after treatment, frustrating both the patient and the physician. Standard BV treatment—metronidazole or clindamycin,\\u000a administered either intravaginally or orally—is followed by relapse in approximately 30% of cases, within one month. Our inability\\u000a to prevent relapse reflects our lack of

Phillip Hay

2000-01-01

159

Bacterial Resistance in Acne  

Microsoft Academic Search

Antibiotics play a major role in acne therapy. Physicians base treatment choices on personal perceptions of efficacy, cost-effectiveness or risk-benefit ratios and rarely take bacterial resistance into account. It is well documented that resistant strains of coagulase-negative staphylococci within the resident skin flora increase in both prevalence and population density as duration of therapy increases. Acne patients represent a considerable

E. A. Eady

1998-01-01

160

Bacterial-like PPP protein phosphatases  

PubMed Central

Reversible phosphorylation is a widespread modification affecting the great majority of eukaryotic cellular proteins, and whose effects influence nearly every cellular function. Protein phosphatases are increasingly recognized as exquisitely regulated contributors to these changes. The PPP (phosphoprotein phosphatase) family comprises enzymes, which catalyze dephosphorylation at serine and threonine residues. Nearly a decade ago, “bacterial-like” enzymes were recognized with similarity to proteins from various bacterial sources: SLPs (Shewanella-like phosphatases), RLPHs (Rhizobiales-like phosphatases), and ALPHs (ApaH-like phosphatases). A recent article from our laboratory appearing in Plant Physiology characterizes their extensive organismal distribution, abundance in plant species, predicted subcellular localization, motif organization, and sequence evolution. One salient observation is the distinct evolutionary trajectory followed by SLP genes and proteins in photosynthetic eukaryotes vs. animal and plant pathogens derived from photosynthetic ancestors. We present here a closer look at sequence data that emphasizes the distinctiveness of pathogen SLP proteins and that suggests that they might represent novel drug targets. A second observation in our original report was the high degree of similarity between the bacterial-like PPPs of eukaryotes and closely related proteins of the “eukaryotic-like” phyla Myxococcales and Planctomycetes. We here reflect on the possible implications of these observations and their importance for future research. PMID:24675170

Kerk, David; Uhrig, R Glen; Moorhead, Greg B

2013-01-01

161

In an early branching metazoan, bacterial colonization of the embryo is controlled by maternal antimicrobial peptides.  

PubMed

Early embryos of many organisms develop outside the mother and are immediately confronted with myriads of potential colonizers. How these naive developmental stages control and shape the bacterial colonization is largely unknown. Here we show that early embryonic stages of the basal metazoan Hydra are able to control bacterial colonization by using maternal antimicrobial peptides. Antimicrobial peptides of the periculin family selecting for a specific bacterial colonization during embryogenesis are produced in the oocyte and in early embryos. If overexpressed in hydra ectodermal epithelial cells, periculin1a drastically reduces the bacterial load, indicating potent antimicrobial activity. Unexpectedly, transgenic polyps also revealed that periculin, in addition to bactericidal activity, changes the structure of the bacterial community. These findings delineate a role for antimicrobial peptides both in selecting particular bacterial partners during development and as important components of a "be prepared" strategy providing transgenerational protection. PMID:20921390

Fraune, Sebastian; Augustin, René; Anton-Erxleben, Friederike; Wittlieb, Jörg; Gelhaus, Christoph; Klimovich, Vladimir B; Samoilovich, Marina P; Bosch, Thomas C G

2010-10-19

162

In an early branching metazoan, bacterial colonization of the embryo is controlled by maternal antimicrobial peptides  

PubMed Central

Early embryos of many organisms develop outside the mother and are immediately confronted with myriads of potential colonizers. How these naive developmental stages control and shape the bacterial colonization is largely unknown. Here we show that early embryonic stages of the basal metazoan Hydra are able to control bacterial colonization by using maternal antimicrobial peptides. Antimicrobial peptides of the periculin family selecting for a specific bacterial colonization during embryogenesis are produced in the oocyte and in early embryos. If overexpressed in hydra ectodermal epithelial cells, periculin1a drastically reduces the bacterial load, indicating potent antimicrobial activity. Unexpectedly, transgenic polyps also revealed that periculin, in addition to bactericidal activity, changes the structure of the bacterial community. These findings delineate a role for antimicrobial peptides both in selecting particular bacterial partners during development and as important components of a “be prepared” strategy providing transgenerational protection. PMID:20921390

Fraune, Sebastian; Augustin, René; Anton-Erxleben, Friederike; Wittlieb, Jörg; Gelhaus, Christoph; Klimovich, Vladimir B.; Samoilovich, Marina P.; Bosch, Thomas C. G.

2010-01-01

163

FAMILY POTYVIRIDAE  

Technology Transfer Automated Retrieval System (TEKTRAN)

The International Committee on the Taxonomy of Viruses potyvirus study group has revised the description of the family Geminiviridae for inclusion in the ICTV 8th report. Characteristic features of each genus within the family is presented. Revised criteria for demarcation and nomenclature of vira...

164

FAMILY GEMINIVIRIDAE  

Technology Transfer Automated Retrieval System (TEKTRAN)

The International Committee on the Taxonomy of Viruses geminivirus study group has revised the description of the family Geminiviridae for inclusion in the ICTV 8th report. Characteristic features of each genus within the family is presented. Revised criteria for demarcation and nomenclature of vi...

165

Family, Extended  

ERIC Educational Resources Information Center

Parents are a child's first and most influential teacher. People hear this truism often, yet nowhere has the author seen it more taken to heart than at Tower Street Elementary School. The school's efforts to form a true partnership with students' families--from involving families in the first day of school, to the principal making home visits, to…

Patton, Jessica Rae

2006-01-01

166

Family Theory and Family Health Research  

PubMed Central

Different family theories can be applied to different aspects of how families experience health and illness. The family health and illness cycle describes the phases of a family's experience, beginning with health promotion and risk reduction, then family vulnerability and disease onset or relapse, family illness appraisal, family acute response, and finally family adaptation to illness and recovery. For each phase, specific family theories that are most appropriate for guiding family and health research are discussed. PMID:21229056

Doherty, William J.

1991-01-01

167

Optimized Expression of IL-12 Cytokine Family  

Cancer.gov

The IL-12 family of cytokines (IL-12, IL-23, and IL-27) plays a role in infection, inflammation and autoimmune diseases. IL-12 is produced by macrophages and dendritic cells in response to certain bacterial and parasitic infections and is a powerful inducer of IFN-gamma production.

168

Insights from 20 years of bacterial genome sequencing.  

PubMed

Since the first two complete bacterial genome sequences were published in 1995, the science of bacteria has dramatically changed. Using third-generation DNA sequencing, it is possible to completely sequence a bacterial genome in a few hours and identify some types of methylation sites along the genome as well. Sequencing of bacterial genome sequences is now a standard procedure, and the information from tens of thousands of bacterial genomes has had a major impact on our views of the bacterial world. In this review, we explore a series of questions to highlight some insights that comparative genomics has produced. To date, there are genome sequences available from 50 different bacterial phyla and 11 different archaeal phyla. However, the distribution is quite skewed towards a few phyla that contain model organisms. But the breadth is continuing to improve, with projects dedicated to filling in less characterized taxonomic groups. The clustered regularly interspaced short palindromic repeats (CRISPR)-Cas system provides bacteria with immunity against viruses, which outnumber bacteria by tenfold. How fast can we go? Second-generation sequencing has produced a large number of draft genomes (close to 90 % of bacterial genomes in GenBank are currently not complete); third-generation sequencing can potentially produce a finished genome in a few hours, and at the same time provide methlylation sites along the entire chromosome. The diversity of bacterial communities is extensive as is evident from the genome sequences available from 50 different bacterial phyla and 11 different archaeal phyla. Genome sequencing can help in classifying an organism, and in the case where multiple genomes of the same species are available, it is possible to calculate the pan- and core genomes; comparison of more than 2000 Escherichia coli genomes finds an E. coli core genome of about 3100 gene families and a total of about 89,000 different gene families. Why do we care about bacterial genome sequencing? There are many practical applications, such as genome-scale metabolic modeling, biosurveillance, bioforensics, and infectious disease epidemiology. In the near future, high-throughput sequencing of patient metagenomic samples could revolutionize medicine in terms of speed and accuracy of finding pathogens and knowing how to treat them. PMID:25722247

Land, Miriam; Hauser, Loren; Jun, Se-Ran; Nookaew, Intawat; Leuze, Michael R; Ahn, Tae-Hyuk; Karpinets, Tatiana; Lund, Ole; Kora, Guruprased; Wassenaar, Trudy; Poudel, Suresh; Ussery, David W

2015-03-01

169

[Therapy of bacterial meningitis].  

PubMed

The therapy of the bacterial purulent meningitis supports itself - at least in the causative organisms appearing most frequently - meningococci, pneumococci - on the application of a sufficiently high and sufficiently long penicillin therapy. In other causative organisms - pseudomonas, E. coli - the therapy demands the aimed use of other antibiotics (gentamycin, carbenicillin, polymyxin). The pneumococcal meningitis with pronounced reference to age shows the highest letality. The urgent admission to hospital must be demanded also when there is the slightest suspicion on the existence of a meningitis. Antibiotic therapy before admission may prevent the demonstration of causative organisms and thus inhibits the aimed therapy. PMID:919649

Förster, E

1977-08-01

170

Family II. Leptospiraceae Hovind-Hougen 1979, 245AL  

Technology Transfer Automated Retrieval System (TEKTRAN)

Bacteria within the Family Leptospiraceae comprise a diverse group of three bacterial genera, Leptospira, Leptonema, and Turneriella. These bacteria are aerobes that consume long-chain fatty acids and alcohols as carbon and energy sources. Some members of this Family cause serious infections in ani...

171

Bacterial symbionts and natural products.  

PubMed

The study of bacterial symbionts of eukaryotic hosts has become a powerful discovery engine for chemistry. This highlight looks at four case studies that exemplify the range of chemistry and biology involved in these symbioses: a bacterial symbiont of a fungus and a marine invertebrate that produce compounds with significant anticancer activity, and bacterial symbionts of insects and nematodes that produce compounds that regulate multilateral symbioses. PMID:21594283

Crawford, Jason M; Clardy, Jon

2011-07-21

172

Bacterial contamination of enteral diets.  

PubMed Central

Enteral feeding solutions can be contaminated by bacterial micro-organisms already present in the ingredients, or introduced during preparation or transport, or in the hospital ward. During jejunostomy feeding without pump or filter, ascending bacterial invasion of the feeding bag is possible. In patients with lowered immune response contaminated feedings can cause serious septic clinical problems. The progressive loss of the nutritional value of the enteral feeding solution by bacterial contamination has to be considered for all patients. PMID:3098643

de Leeuw, I H; Vandewoude, M F

1986-01-01

173

Animal Models of Bacterial Keratitis  

PubMed Central

Bacterial keratitis is a disease of the cornea characterized by pain, redness, inflammation, and opacity. Common causes of this disease are Pseudomonas aeruginosa and Staphylococcus aureus. Animal models of keratitis have been used to elucidate both the bacterial factors and the host inflammatory response involved in the disease. Reviewed herein are animal models of bacterial keratitis and some of the key findings in the last several decades. PMID:21274270

Marquart, Mary E.

2011-01-01

174

Nanoparticle approaches against bacterial infections.  

PubMed

Despite the wide success of antibiotics, the treatment of bacterial infections still faces significant challenges, particularly the emergence of antibiotic resistance. As a result, nanoparticle drug delivery platforms including liposomes, polymeric nanoparticles, dendrimers, and various inorganic nanoparticles have been increasingly exploited to enhance the therapeutic effectiveness of existing antibiotics. This review focuses on areas where nanoparticle approaches hold significant potential to advance the treatment of bacterial infections. These areas include targeted antibiotic delivery, environmentally responsive antibiotic delivery, combinatorial antibiotic delivery, nanoparticle-enabled antibacterial vaccination, and nanoparticle-based bacterial detection. In each area we highlight the innovative antimicrobial nanoparticle platforms and review their progress made against bacterial infections. PMID:25044325

Gao, Weiwei; Thamphiwatana, Soracha; Angsantikul, Pavimol; Zhang, Liangfang

2014-01-01

175

Bacterial Fruit Blotch of Watermelon  

E-print Network

Bacterial fruit blotch is a disease occurring sporadically in almost all areas of Texas where watermelons are grown. This publication discusses symptoms, diagnosis and disease development and management....

Isakeit, Thomas

1999-06-28

176

Bacterial genotoxicity bioreporters  

PubMed Central

Summary Ever since the introduction of the Salmonella typhimurium mammalian microsome mutagenicity assay (the ‘Ames test’) over three decades ago, there has been a constant development of additional genotoxicity assays based upon the use of genetically engineered microorganisms. Such assays rely either on reversion principles similar to those of the Ames test, or on promoter–reporter fusions that generate a quantifiable dose?dependent signal in the presence of potential DNA damaging compounds and the induction of repair mechanisms; the latter group is the subject of the present review. Some of these assays were only briefly described in the scientific literature, whereas others have been developed all the way to commercial products. Out of these, only one, the umu?test, has been fully validated and ISO? and OECD standardized. Here we review the main directions undertaken in the construction and testing of bacterial?based genotoxicity bioassays, including the attempts to incorporate at least a partial metabolic activation capacity into the molecular design. We list the genetic modifications introduced into the tester strains, compare the performance of the different assays, and briefly describe the first attempts to incorporate such bacterial reporters into actual genotoxicity testing devices. PMID:21255340

Biran, Alva; Yagur?Kroll, Sharon; Pedahzur, Rami; Buchinger, Sebastian; Reifferscheid, Georg; Ben?Yoav, Hadar; Shacham?Diamand, Yosi; Belkin, Shimshon

2010-01-01

177

Bacterial body plans  

PubMed Central

The bacterium Serratia marcescens produces a plethora of multicellular shapes of different colorations on solid substrates, allowing immediate visual detection of varieties. Such a plasticity allows studies on multicellular community scale spanning two extremes, from well-elaborated individual colonies to undifferentiated cell mass. For a single strain and medium, we obtained a range of different multicellular bodies, depending on the layout of initial plating. Four principal factors affecting the morphogenetic pathways of such bodies can be distinguished: (1) amount, density and distribution pattern of founder cells; (2) the configuration of surrounding free medium; (3) the presence and character of other bacterial bodies sharing the same niche; and (4) self-perception, resulting in delimitation towards other bodies. The last feature results in an ability of well-formed multicellular individuals to maintain their identity upon a close mutual contact, as well as in spontaneous separation of cell masses in experimental chimeras. We propose an “embryo-like” colony model where multicellular bacterial bodies develop along genuine ontogenetic pathways inherent to the given species (clone), while external shaping forces (like nutrient gradients, pH, etc.,) exert not formative, but only regulative roles in the process. PMID:19513204

Rieger, Tomáš; Neubauer, Zden?k; Blah?šková, Anna; Cvr?ková, Fatima

2008-01-01

178

Bacterial biosorbents and biosorption.  

PubMed

Biosorption is a technique that can be used for the removal of pollutants from waters, especially those that are not easily biodegradable such as metals and dyes. A variety of biomaterials are known to bind these pollutants, including bacteria, fungi, algae, and industrial and agricultural wastes. In this review, the biosorption abilities of bacterial biomass towards dyes and metal ions are emphasized. The properties of the cell wall constituents, such as peptidoglycan, and the role of functional groups, such as carboxyl, amine and phosphonate, are discussed on the basis of their biosorption potentials. The binding mechanisms, as well as the parameters influencing the passive uptake of pollutants, are analyzed. A detailed description of isotherm and kinetic models and the importance of mechanistic modeling are presented. A systematic comparison of literature, based on the metal/dye binding capacity of bacterial biomass under different conditions, is also provided. To enhance biosorption capacity, biomass modifications through chemical methods and genetic engineering are discussed. The problems associated with microbial biosorption are analyzed, and suitable remedies discussed. For the continuous treatment of effluents, an up-flow packed column configuration is suggested and the factors influencing its performance are discussed. The present review also highlights the necessity for the examination of biosorbents within real situations, as competition between solutes and water quality may affect the biosorption performance. Thus, this article reviews the achievements and current status of biosorption technology, and hopes to provide insights into this research frontier. PMID:18353595

Vijayaraghavan, K; Yun, Yeoung-Sang

2008-01-01

179

Family History  

MedlinePLUS

... Brain Aneurysm Statistics and Facts Seeking Medical Attention Pediatric Aneurysms Brain Aneurysm Causes and Risk Factors Family History Early Detection and Screening Unruptured Brain Aneurysms Subarachnoid Hemorrhage Treatment Options Aneurysm Complications Post ...

180

Tomorrow's Family  

ERIC Educational Resources Information Center

Author states that "...the traditional form of family which has been the norm in recent times in the West will persist, but will be forced to "move over" to accommodate other forms of domestic life." (Author)

Pickett, Robert S.

1977-01-01

181

Family Issues  

MedlinePLUS

... Bullying Prevention Preparedness Tips for Families Tips for First Responders Serving Victims of Crime Take Me Home Emergency Preparedness Related Links Safe and Sound Task Force Voices Blog DONATE BECOME A MEMBER ...

182

FAMILIES FIRST: Keys to Successful Family Functioning Family Roles  

E-print Network

FAMILIES FIRST: Keys to Successful Family Functioning Family Roles Rick Peterson, Extension or family status. An equal opportunity/affirmative action employer. Issued in furtherance of Cooperative. publication 350-093 Types of family Roles Family roles are the recurrent patterns of behavior by which

Liskiewicz, Maciej

183

A Common Fold Mediates Vertebrate Defense and Bacterial Attack  

SciTech Connect

Proteins containing membrane attack complex/perforin (MACPF) domains play important roles in vertebrate immunity, embryonic development, and neural-cell migration. In vertebrates, the ninth component of complement and perforin form oligomeric pores that lyse bacteria and kill virus-infected cells, respectively. However, the mechanism of MACPF function is unknown. We determined the crystal structure of a bacterial MACPF protein, Plu-MACPF from Photorhabdus luminescens, to 2.0 angstrom resolution. The MACPF domain reveals structural similarity with poreforming cholesterol-dependent cytolysins (CDCs) from Gram-positive bacteria. This suggests that lytic MACPF proteins may use a CDC-like mechanism to form pores and disrupt cell membranes. Sequence similarity between bacterial and vertebrate MACPF domains suggests that the fold of the CDCs, a family of proteins important for bacterial pathogenesis, is probably used by vertebrates for defense against infection.

Rosado, Carlos J.; Buckle, Ashley M.; Law, Ruby H.P.; Butcher, Rebecca E.; Kan, Wan-Ting; Bird, Catherina H.; Ung, Kheng; Browne, Kylie A.; Baran, Katherine; Bashtannyk-Puhalovich, Tanya A.; Faux, Noel G.; Wong, Wilson; Porter, Corrine J.; Pike, Robert N.; Ellisdon, Andrew M.; Pearce, Mary C.; Bottomley, Stephen P.; Emsley, Jonas; Smith, A. Ian; Rossjohn, Jamie; Hartland, Elizabeth L.; Voskoboinik, Ilia; Trapani, Joseph A.; Bird, Phillip I.; Dunstone, Michelle A.; Whisstock, James C. (PMCI-A); (Monash); (Nottingham)

2008-10-02

184

Family Limitation  

PubMed Central

Dr Robert Smith surveys the history of birth control and sounds a warning for the future of mankind, if the population explosion is allowed to continue unchecked. He stresses the importance of the role of the general practitioner in the limitation of births. Sir Theodore Fox describes the work of the Family Planning Association and stresses that, increasingly, this is a specialist service covering all aspects of fertility. He also feels that the general practitioner has a role in family planning. PMID:5954261

Smith, Robert

1966-01-01

185

Role of bacterial volatile compounds in bacterial biology.  

PubMed

Bacterial interactions with neighboring microorganisms via production of small metabolites enable bacteria to respond and adapt to environmental changes. The study of intercellular interactions primarily focused on soluble metabolites, but bacteria also produce and release into their headspace a wide variety of volatile secondary metabolites, the ecological roles of which have generally been overlooked. However, bacterial volatile compounds are known to contribute to interkingdom interactions (plant, fungi and nematodes), and recent studies also identified their at-a-distance influence on bacterial behavior. The present review describes the biological roles of bacterial volatile compounds in inter- and intraspecies bacterial interactions, a new and yet unexplored research area, with potential clinical and industrial applications. PMID:25725014

Audrain, Bianca; Farag, Mohamed A; Ryu, Choong-Min; Ghigo, Jean-Marc

2015-03-01

186

Uncovering common bacterial skin infections.  

PubMed

The four most common bacterial skin infections are impetigo, erysipelas, cellulitis, and folliculitis. This article summarizes current information about the etiology, clinical presentation, diagnosis, prevention, treatment, and implications for primary care practice needed to effectively diagnose and treat common bacterial skin infections. PMID:23361375

Napierkowski, Daria

2013-03-10

187

The RND Permease Superfamily: An Ancient, Ubiquitous and Diverse Family that Includes Human Disease and Development Proteins  

Microsoft Academic Search

A previous report identified and classified a small family of Gram-negative bacterial drug and heavy metal efflux permeases, now commonly referred to as the RND family (TC no. 2.6). We here show that this family is actually a ubiquitous superfamily with representation in all major kingdoms. We report phylogenetic analyses that define seven families within the RND superfamily as follows:

Tsai-Tien Tseng; Kevin S. Gratwick; Justin Kollman; Daniel Park; Dietrich H. Nies; André Goffeau; Milton H. Saier

188

7 CFR 58.135 - Bacterial estimate.  

Code of Federal Regulations, 2010 CFR

...with respect to bacterial estimates: (1) Whenever the bacterial estimate indicates the presence of more than 500,000 bacteria per ml., the producer shall be notified with a warning of the excessive bacterial estimate. (2) Whenever two...

2010-01-01

189

Evolution of Bacterial Suicide  

NASA Astrophysics Data System (ADS)

While active, controlled cellular suicide (autolysis) in bacteria is commonly observed, it has been hard to argue that autolysis can be beneficial to an individual who commits it. We propose a theoretical model that predicts that bacterial autolysis is evolutionarily advantageous to an individual and would fixate in physically structured environments for stationary phase colonies. We perform spatially resolved agent-based simulations of the model, which predict that lower mixing in the environment results in fixation of a higher autolysis rate from a single mutated cell, regardless of the colony's genetic diversity. We argue that quorum sensing will fixate as well, even if initially rare, if it is coupled to controlling the autolysis rate. The model does not predict a strong additional competitive advantage for cells where autolysis is controlled by quorum sensing systems that distinguish self from nonself. These predictions are broadly supported by recent experimental results in B. subtilis and S. pneumoniae.

Tchernookov, Martin; Nemenman, Ilya

2013-03-01

190

Bacterial Identification Virtual Lab  

NSDL National Science Digital Library

Created by the Howard Hughes Medical Institute (HHMI), the Virtual Bacterial Identification Lab provides interested parties with a great way to learn about the science and techniques used to identify different types of bacteria based on their DNA sequences. Visitors can enter the lab and get started by preparing samples from a patient, copying the desired pieces of the DNA, and then sequencing and analyzing the DNA. The entire experience is quite interactive: visitors can record their observations in the Notebook area and also learn about the various samples, which were obtained from stool, lymph nodes, urine, and blood. Finally, there's the Reference area, which contains a glossary of terms, a list of tools in the lab, and an encyclopedia of selected bacteria and other pathogens.

191

Marine Bacterial Sialyltransferases  

PubMed Central

Sialyltransferases transfer N-acetylneuraminic acid (Neu5Ac) from the common donor substrate of these enzymes, cytidine 5?-monophospho-N-acetylneuraminic acid (CMP-Neu5Ac), to acceptor substrates. The enzymatic reaction products including sialyl-glycoproteins, sialyl-glycolipids and sialyl-oligosaccharides are important molecules in various biological and physiological processes, such as cell-cell recognition, cancer metastasis, and virus infection. Thus, sialyltransferases are thought to be important enzymes in the field of glycobiology. To date, many sialyltransferases and the genes encoding them have been obtained from various sources including mammalian, bacterial and viral sources. During the course of our research, we have detected over 20 bacteria that produce sialyltransferases. Many of the bacteria we isolated from marine environments are classified in the genus Photobacterium or the closely related genus Vibrio. The paper reviews the sialyltransferases obtained mainly from marine bacteria. PMID:21139844

Yamamoto, Takeshi

2010-01-01

192

The bacterial proteogenomic pipeline  

PubMed Central

Background Proteogenomics combines the cutting-edge methods from genomics and proteomics. While it has become cheap to sequence whole genomes, the correct annotation of protein coding regions in the genome is still tedious and error prone. Mass spectrometry on the other hand relies on good characterizations of proteins derived from the genome, but can also be used to help improving the annotation of genomes or find species specific peptides. Additionally, proteomics is widely used to find evidence for differential expression of proteins under different conditions, e.g. growth conditions for bacteria. The concept of proteogenomics is not altogether new, in-house scripts are used by different labs and some special tools for eukaryotic and human analyses are available. Results The Bacterial Proteogenomic Pipeline, which is completely written in Java, alleviates the conducting of proteogenomic analyses of bacteria. From a given genome sequence, a naïve six frame translation is performed and, if desired, a decoy database generated. This database is used to identify MS/MS spectra by common peptide identification algorithms. After combination of the search results and optional flagging for different experimental conditions, the results can be browsed and further inspected. In particular, for each peptide the number of identifications for each condition and the positions in the corresponding protein sequences are shown. Intermediate and final results can be exported into GFF3 format for visualization in common genome browsers. Conclusions To facilitate proteogenomics analyses the Bacterial Proteogenomic Pipeline is a set of comprehensive tools running on common desktop computers, written in Java and thus platform independent. The pipeline allows integrating peptide identifications from various algorithms and emphasizes the visualization of spectral counts from different experimental conditions. PMID:25521444

2014-01-01

193

Comparative Genomic Analyses of the Bacterial Phosphotransferase System  

PubMed Central

We report analyses of 202 fully sequenced genomes for homologues of known protein constituents of the bacterial phosphoenolpyruvate-dependent phosphotransferase system (PTS). These included 174 bacterial, 19 archaeal, and 9 eukaryotic genomes. Homologues of PTS proteins were not identified in archaea or eukaryotes, showing that the horizontal transfer of genes encoding PTS proteins has not occurred between the three domains of life. Of the 174 bacterial genomes (136 bacterial species) analyzed, 30 diverse species have no PTS homologues, and 29 species have cytoplasmic PTS phosphoryl transfer protein homologues but lack recognizable PTS permeases. These soluble homologues presumably function in regulation. The remaining 77 species possess all PTS proteins required for the transport and phosphorylation of at least one sugar via the PTS. Up to 3.2% of the genes in a bacterium encode PTS proteins. These homologues were analyzed for family association, range of protein types, domain organization, and organismal distribution. Different strains of a single bacterial species often possess strikingly different complements of PTS proteins. Types of PTS protein domain fusions were analyzed, showing that certain types of domain fusions are common, while others are rare or prohibited. Select PTS proteins were analyzed from different phylogenetic standpoints, showing that PTS protein phylogeny often differs from organismal phylogeny. The results document the frequent gain and loss of PTS protein-encoding genes and suggest that the lateral transfer of these genes within the bacterial domain has played an important role in bacterial evolution. Our studies provide insight into the development of complex multicomponent enzyme systems and lead to predictions regarding the types of protein-protein interactions that promote efficient PTS-mediated phosphoryl transfer. PMID:16339738

Barabote, Ravi D.; Saier, Milton H.

2005-01-01

194

Bacterial Meningitis Online Enrollment Only Exemption Request  

E-print Network

Bacterial Meningitis Online Enrollment Only Exemption Request Return form to: The University of completed vaccination against Bacterial Meningitis. By signing this letter, you are stating that you have

O'Toole, Alice J.

195

Laboratory diagnosis of bacterial gastroenteritis.  

PubMed

Bacterial gastroenteritis is a disease that is pervasive in both the developing and developed worlds. While for the most part bacterial gastroenteritis is self-limiting, identification of an etiological agent by bacterial stool culture is required for the management of patients with severe or prolonged diarrhea, symptoms consistent with invasive disease, or a history that may predict a complicated course of disease. Importantly, characterization of bacterial enteropathogens from stool cultures in clinical laboratories is one of the primary means by which public health officials identify and track outbreaks of bacterial gastroenteritis. This article provides guidance for clinical microbiology laboratories that perform stool cultures. The general characteristics, epidemiology, and clinical manifestations of key bacterial enteropathogens are summarized. Information regarding optimal specimen collection, transport, and processing and current diagnostic tests and testing algorithms is provided. This article is an update of Cumitech 12A (P. H. Gilligan, J. M. Janda, M. A. Karmali, and J. M. Miller, Cumitech 12A, Laboratory diagnosis of bacterial diarrhea, 1992). PMID:25567220

Humphries, Romney M; Linscott, Andrea J

2015-01-01

196

Infectious delivery of alphaherpesvirus bacterial artificial chromosomes.  

PubMed

Bacterial artificial chromosomes (BACs) can accommodate and stably propagate the genomes of large DNA viruses in E. coli. As DNA virus genomes are often per se infectious upon transfection into mammalian cells, their cloning in BACs and easy modification by homologous recombination in bacteria has become an important strategy to investigate the functions of individual virus genes. This chapter describes a strategy to clone the genomes of viruses of the Alphaherpesvirinae subfamily within the family of the Herpesviridae, which is a group of large DNA viruses that can establish both lytic and latent infections in most animal species including humans. The cloning strategy includes the following steps: (1) Construction of a transfer plasmid that contains the BAC backbone with selection and screening markers, and targeting sequences which support homologous recombination between the transfer plasmid and the alphaherpesvirus genome. (2) Introduction of the transfer plasmid sequences into the alphaherpesvirus genome via homologous recombination in mammalian cells. (3) Isolation of recombinant virus genomes containing the BAC backbone sequences from infected mammalian cells and electroporation into E. coli. (4) Preparation of infectious BAC DNA from bacterial cultures and transfection into mammalian cells. (5) Isolation and characterization of progeny virus. PMID:25239748

Tobler, Kurt; Fraefel, Cornel

2015-01-01

197

Family Hypnotherapy.  

ERIC Educational Resources Information Center

A therapeutic model to help families activate experiential and right hemispheric functioning through hypnosis is presented in detail, together with a clinical illustration. Different situations in which this model is effective are mentioned and one such set of circumstances is described. (Author)

Araoz, Daniel L.; Negley-Parker, Esther

1985-01-01

198

Family matters.  

PubMed

'Why do you want to know?' a nurse friend was recently asked when she phoned the ward to ask how her father was. He was very ill in his local hospital and she and the rest of the family were on tenterhooks, anxious for news. PMID:25827999

Bates, Jane

2015-04-01

199

FAMILY TYMOVIRIDAE  

Technology Transfer Automated Retrieval System (TEKTRAN)

This article provides a brief review of the taxonomic structure, virion properties, genome organization and replication strategy, antigenic properties, and biological properties of viruses in the family Tymoviridae. Criteria for demarcation of genus and species are provided. A brief review of each...

200

Family Grouping.  

ERIC Educational Resources Information Center

This report describes an observational study of one family-grouped classroom, a system in which elementary school children remain with the same teacher for two or more years. The class was composed of junior kindergarten, senior kindergarten, and grade 1 pupils. Each child was observed over a period of one year. A detailed observation schedule,…

Young, Vivienne; Reich, Carol

201

Serving Families.  

ERIC Educational Resources Information Center

Parent Services Project (PSP), the first comprehensive program of resources and mental health activities for parents offered at child care centers in the San Francisco Bay Area (California), has expanded to centers in six states, serving over 19,000 families. This report describes the program's history, aims, and achievements, along with specific…

Link, Geoffrey; Beggs, Marjorie; Seiderman, Ethel

202

Canadian guidelines for acute bacterial rhinosinusitis  

PubMed Central

Objective To provide a clinical summary of the Canadian clinical practice guidelines for acute bacterial rhinosinusitis (ABRS) that includes relevant considerations for family physicians. Quality of evidence Guideline authors performed a systematic literature search and drafted recommendations. Recommendations received both strength of evidence and strength of recommendation ratings. Input from external content experts was sought, as was endorsement from Canadian medical societies (Association of Medical Microbiology and Infectious Disease Canada, Canadian Society of Allergy and Clinical Immunology, Canadian Society of Otolaryngology—Head and Neck Surgery, Canadian Association of Emergency Physicians, and the Family Physicians Airways Group of Canada). Main message Diagnosis of ABRS is based on the presence of specific symptoms and their duration; imaging or culture are not needed in uncomplicated cases. Treatment is dependent on symptom severity, with intranasal corticosteroids (INCSs) recommended as monotherapy for mild and moderate cases, although the benefit might be modest. Use of INCSs plus antibiotics is reserved for patients who fail to respond to INCSs after 72 hours, and for initial treatment of patients with severe symptoms. Antibiotic selection must account for the suspected pathogen, the risk of resistance, comorbid conditions, and local antimicrobial resistance trends. Adjunct therapies such as nasal saline irrigation are recommended. Failure to respond to treatment, recurrent episodes, and signs of complications should prompt referral to an otolaryngologist. The guidelines address situations unique to the Canadian health care environment, including actions to take during prolonged wait periods for specialist referral or imaging. Conclusion The Canadian guidelines provide up-to-date recommendations for diagnosis and treatment of ABRS that reflect an evolving understanding of the disease. In addition, the guidelines offer useful tools to help clinicians discern viral from bacterial episodes, as well as optimally manage their patients with ABRS. PMID:24627376

Kaplan, Alan

2014-01-01

203

Electromagnetism of Bacterial Growth  

NASA Astrophysics Data System (ADS)

There has been increasing concern from the public about personal health due to the significant rise in the daily use of electrical devices such as cell phones, radios, computers, GPS, video games and television. All of these devices create electromagnetic (EM) fields, which are simply magnetic and electric fields surrounding the appliances that simultaneously affect the human bio-system. Although these can affect the human system, obstacles can easily shield or weaken the electrical fields; however, magnetic fields cannot be weakened and can pass through walls, human bodies and most other objects. The present study was conducted to examine the possible effects of bacteria when exposed to magnetic fields. The results indicate that a strong causal relationship is not clear, since different magnetic fields affect the bacteria differently, with some causing an increase in bacterial cells, and others causing a decrease in the same cells. This phenomenon has yet to be explained, but the current study attempts to offer a mathematical explanation for this occurrence. The researchers added cultures to the magnetic fields to examine any effects to ion transportation. Researchers discovered ions such as potassium and sodium are affected by the magnetic field. A formula is presented in the analysis section to explain this effect.

Ainiwaer, Ailiyasi

2011-10-01

204

Sculpting the Bacterial Cell  

PubMed Central

Prokaryotes come in a wide variety of shapes, determined largely by natural selection, physical constraints, and patterns of cell growth and division. Because of their relative simplicity, bacterial cells are excellent models for how genes and proteins can directly determine morphology. Recent advances in cytological methods for bacteria have shown that distinct cytoskeletal filaments composed of actin and tubulin homologs are important for guiding growth patterns of the cell wall in bacteria, and that the glycan strands that constitute the wall are generally perpendicular to the direction of growth. This cytoskeleton-directed cell wall patterning is strikingly reminiscent of how plant cell wall growth is regulated by microtubules. In rod-shaped bacilli, helical cables of actin-like MreB protein stretch along the cell length and orchestrate elongation of the cell wall, whereas the tubulin-like FtsZ protein directs formation of the division septum and the resulting cell poles. The overlap and interplay between these two systems and the peptidoglycan-synthesizing enzymes they recruit are the major driving forces of cylindrical shapes. Round cocci, on the other hand, have lost their MreBcables and instead mustgrowmainly via their division septum, giving them their characteristic round or ovoid shapes. Other bacteria that lack MreB homologs or even cell walls usedistinct cytoskeletal systemsto maintain their distinct shapes. Here I review what is known about the mechanisms that determine the shape of prokaryotic cells. PMID:19906583

Margolin, William

2014-01-01

205

The bacterial nucleoid revisited.  

PubMed Central

This review compares the results of different methods of investigating the morphology of nucleoids of bacteria grown under conditions favoring short generation times. We consider the evidence from fixed and stained specimens, from phase-contrast and fluorescence microscopy of growing bacteria, and from electron microscopy of whole as well as thinly sectioned ones. It is concluded that the nucleoid of growing cells is in a dynamic state: part of the chromatin is "pulled out" of the bulk of the nucleoid in order to be transcribed. This activity is performed by excrescences which extend far into the cytoplasm so as to reach the maximum of available ribosomes. Different means of fixation provide markedly different views of the texture of the DNA-containing plasm of the bulk of the nucleoid. Conventional chemical fixatives stabilize the cytoplasm of bacteria but not their protein-low chromatin. Uranyl acetate does cross-link the latter well but only if the cytoplasm has first been fixed conventionally. In the interval between the two fixations, the DNA arranges itself in liquid-crystalline form, supposedly because of loss of supercoiling. In stark contrast, cryofixation preserves bacterial chromatin in a finely granular form, believed to reflect its native strongly negatively supercoiled state. In dinoflagellates the DNA of their permanently visible chromosomes (also low in histone-like protein) is natively present as a liquid crystal. The arrangement of chromatin in Epulocystis fishelsoni, one of the largest known prokaryotes, is briefly described. Images PMID:7521510

Robinow, C; Kellenberger, E

1994-01-01

206

[Bacterial meningitis in neonates].  

PubMed

A retrospective study of the clinical features and management of 27 newborns with meningitis is presented. All were treated in the China Medical College Hospital between July 1981 and July 1988. Seven were premature and twenty were full term. There were 11 males and 16 females. Five infants had low birth weight (less than 2500 g) and 12 cases were diagnosed in the first week of life (early onset). E.coli was the predominant pathogen. The most common presenting manifestations were nonspecific in nature-fever, poor feeding, respiratory distress and poor activity, etc... Six patients died during the period of acute illness and the case fatality rate was 22.2%. Of the 21 patients who survived, six had sequelae (four hydrocephalus, one subdural effusion, one microcephaly), giving an over-all rate of 19 percent in the survivors. The presence of gram-negative bacterial infection and high protein content in CSF correlated significantly with the higher mortality rate. PMID:2275365

Wu, S F; Chang, Y C; Tsai, C H

1990-01-01

207

Bacterial Brain Abscess  

PubMed Central

Significant advances in the diagnosis and management of bacterial brain abscess over the past several decades have improved the expected outcome of a disease once regarded as invariably fatal. Despite this, intraparenchymal abscess continues to present a serious and potentially life-threatening condition. Brain abscess may result from traumatic brain injury, prior neurosurgical procedure, contiguous spread from a local source, or hematogenous spread of a systemic infection. In a significant proportion of cases, an etiology cannot be identified. Clinical presentation is highly variable and routine laboratory testing lacks sensitivity. As such, a high degree of clinical suspicion is necessary for prompt diagnosis and intervention. Computed tomography and magnetic resonance imaging offer a timely and sensitive method of assessing for abscess. Appearance of abscess on routine imaging lacks specificity and will not spare biopsy in cases where the clinical context does not unequivocally indicate infectious etiology. Current work with advanced imaging modalities may yield more accurate methods of differentiation of mass lesions in the brain. Management of abscess demands a multimodal approach. Surgical intervention and medical therapy are necessary in most cases. Prognosis of brain abscess has improved significantly in the recent decades although close follow-up is required, given the potential for long-term sequelae and a risk of recurrence. PMID:25360205

Patel, Kevin

2014-01-01

208

Bacterial phospholipases C.  

PubMed Central

A variety of pathogenic bacteria produce phospholipases C, and since the discovery in 1944 that a bacterial toxin (Clostridium perfringens alpha-toxin) possessed an enzymatic activity, there has been considerable interest in this class of proteins. Initial speculation that all phospholipases C would have lethal properties has not been substantiated. Most of the characterized enzymes fall into one of four groups of structurally related proteins: the zinc-metallophospholipases C, the sphingomyelinases, the phosphatidylinositol-hydrolyzing enzymes, and the pseudomonad phospholipases C. The zinc-metallophospholipases C have been most intensively studied, and lethal toxins within this group possess an additional domain. The toxic phospholipases C can interact with eukaryotic cell membranes and hydrolyze phosphatidylcholine and sphingomyelin, leading to cell lysis. However, measurement of the cytolytic potential or lethality of phospholipases C may not accurately indicate their roles in the pathogenesis of disease. Subcytolytic concentrations of phospholipase C can perturb host cells by activating the arachidonic acid cascade or protein kinase C. Nonlethal phospholipases C, such as the Listeria monocytogenes PLC-A, appear to enhance the release of the organism from the host cell phagosome. Since some phospholipases C play important roles in the pathogenesis of disease, they could form components of vaccines. A greater understanding of the modes of action and structure-function relationships of phospholipases C will facilitate the interpretation of studies in which these enzymes are used as membrane probes and will enhance the use of these proteins as models for eukaryotic phospholipases C. PMID:8336671

Titball, R W

1993-01-01

209

The rare bacterial biosphere.  

PubMed

All communities are dominated by a few species that account for most of the biomass and carbon cycling. On the other hand, a large number of species are represented by only a few individuals. In the case of bacteria, these rare species were until recently invisible. Owing to their low numbers, conventional molecular techniques could not retrieve them. Isolation in pure culture was the only way to identify some of them, but current culturing techniques are unable to isolate most of the bacteria in nature. The recent development of fast and cheap high-throughput sequencing has begun to allow access to the rare species. In the case of bacteria, the exploration of this rare biosphere has several points of interest. First, it will eventually produce a reasonable estimate of the total number of bacterial taxa in the oceans; right now, we do not even know the right order of magnitude. Second, it will answer the question of whether "everything is everywhere." Third, it will require hypothesizing and testing the ecological mechanisms that allow subsistence of many species in low numbers. And fourth, it will open an avenue of research into the immense reserve of genes with potential applications hidden in the rare biosphere. PMID:22457983

Pedrós-Alió, Carlos

2012-01-01

210

New Bacterial Meningitis Vaccine Approved  

MedlinePLUS

... on this page, please enable JavaScript. New Bacterial Meningitis Vaccine Approved Bexsero prevents deadly infection of spinal ... Monday, January 26, 2015 Related MedlinePlus Pages Immunization Meningitis MONDAY, Jan. 26, 2015 (HealthDay News) -- The Bexsero ...

211

Radiation effects on bacterial cells  

NASA Technical Reports Server (NTRS)

Study reveals the physicochemical and biochemical mechanisms which alter or modify the effects of high-energy radiation on living cells. An in-depth discussion is presented emphasizing the importance of optimizing bacterial treatment with glycerol.

Powers, E. L.

1968-01-01

212

Doug Berndt Evaluated Bacterial Assay  

USGS Multimedia Gallery

USGS microbiology technician evaluates a bacterial assay to determine the cause of a wildlife mortality. The USGS National Wildlife Health Center works to identify, track, and prevent wildlife disease....

213

Family Therapy and Disturbed Families.  

ERIC Educational Resources Information Center

Presented at a conference at which authors represented major theoretical positions in the field, most of the papers use family therapy as an important source of observations or ideas, or as a means to pinpoint methodological problems. Papers are grouped in sections as follows: four which introduce the reader to the field of specialization, provide…

Zuk, Gerald H., Ed.; Boszormenyi-Nagy, Ivan, Ed.

214

Bacterial Endophthalmitis Following Cataract Surgery  

Microsoft Academic Search

Cataracts are the most common cause of blindness in the world and cataract surgery is one of the most common surgical procedures\\u000a performed. During surgery the opacified crystalline lens is removed and replaced with a lens implant. Bacterial infection\\u000a of the internal eye (bacterial endophthalmitis) following cataract surgery appears to have increased since the 1990s. The\\u000a infection is the result

M. E. Zegans; C. M. Toutain-Kidd; M. S. Gilmore

215

Family Therapy with Families Having Delinquent Offspring  

ERIC Educational Resources Information Center

Family therapy with families of delinquent children provokes a number of defensive maneuvers to avoid family involvement in solving their problems. Many families view delinquent behavior as others view psychopathology. The problem is to help the family deal with one another and work together. (Author)

Johnson, Thomas F.

1975-01-01

216

Family Caregivers  

Microsoft Academic Search

Caregiving an elder with cancer has the potential to be rewarding and meaningful but is often described as burdensome and\\u000a overwhelming because caregiver needs are frequently unmet. As the provision of care has transitioned from the hospital to\\u000a outpatient settings, family caregivers have take responsibility for the day-to-day care of their ill loved ones at home [1–4].\\u000a Despite the fact

Betty R. Ferrell; Polly Mazanec

217

Updating the Vibrio clades defined by multilocus sequence phylogeny: proposal of eight new clades, and the description of Vibrio tritonius sp. nov.  

PubMed Central

To date 142 species have been described in the Vibrionaceae family of bacteria, classified into seven genera; Aliivibrio, Echinimonas, Enterovibrio, Grimontia, Photobacterium, Salinivibrio and Vibrio. As vibrios are widespread in marine environments and show versatile metabolisms and ecologies, these bacteria are recognized as one of the most diverse and important marine heterotrophic bacterial groups for elucidating the correlation between genome evolution and ecological adaptation. However, on the basis of 16S rRNA gene phylogeny, we could not find any robust monophyletic lineages in any of the known genera. We needed further attempts to reconstruct their evolutionary history based on multilocus sequence analysis (MLSA) and/or genome wide taxonomy of all the recognized species groups. In our previous report in 2007, we conducted the first broad multilocus sequence analysis (MLSA) to infer the evolutionary history of vibrios using nine housekeeping genes (the 16S rRNA gene, gapA, gyrB, ftsZ, mreB, pyrH, recA, rpoA, and topA), and we proposed 14 distinct clades in 58 species of Vibrionaceae. Due to the difficulty of designing universal primers that can amplify the genes for MLSA in every Vibrionaceae species, some clades had yet to be defined. In this study, we present a better picture of an updated molecular phylogeny for 86 described vibrio species and 10 genome sequenced Vibrionaceae strains, using 8 housekeeping gene sequences. This new study places special emphasis on (1) eight newly identified clades (Damselae, Mediterranei, Pectenicida, Phosphoreum, Profundum, Porteresiae, Rosenbergii, and Rumoiensis); (2) clades amended since the 2007 proposal with recently described new species; (3) orphan clades of genomospecies F6 and F10; (4) phylogenetic positions defined in 3 genome-sequenced strains (N418, EX25, and EJY3); and (5) description of V. tritonius sp. nov., which is a member of the “Porteresiae” clade. PMID:24409173

Sawabe, Tomoo; Ogura, Yoshitoshi; Matsumura, Yuta; Feng, Gao; Amin, AKM Rohul; Mino, Sayaka; Nakagawa, Satoshi; Sawabe, Toko; Kumar, Ramesh; Fukui, Yohei; Satomi, Masataka; Matsushima, Ryoji; Thompson, Fabiano L.; Gomez-Gil, Bruno; Christen, Richard; Maruyama, Fumito; Kurokawa, Ken; Hayashi, Tetsuya

2013-01-01

218

Genomics of Pathogenic Vibrio Species  

NASA Astrophysics Data System (ADS)

Members of the heterotrophic bacterial family Vibrionaceae are native inhabitants of aquatic environments worldwide, constituting a diverse and abundant component of marine microbial organisms. Over 60 species of the genus Vibrio have been identified (Thompson et al., 2004) and their phenotypic heterogeneity is well documented. The ecology of the genus remains less well understood, however, despite reports that vibrios are the dominant microorganisms inhabiting the superficial water layer and colonizing the chitinous exoskeleton of zooplankton (e.g., copepods, Thompson et al., 2004). Although some species were originally isolated from seawater as free living organisms, most were isolated in association with marine life such as bivalves, fish, eels, or shrimp.

Dziejman, Michelle; Yildiz, Fitnat H.

219

Gram-Negative Bacterial Sensors for Eukaryotic Signal Molecules  

PubMed Central

Ample evidence exists showing that eukaryotic signal molecules synthesized and released by the host can activate the virulence of opportunistic pathogens. The sensitivity of prokaryotes to host signal molecules requires the presence of bacterial sensors. These prokaryotic sensors, or receptors, have a double function: stereospecific recognition in a complex environment and transduction of the message in order to initiate bacterial physiological modifications. As messengers are generally unable to freely cross the bacterial membrane, they require either the presence of sensors anchored in the membrane or transporters allowing direct recognition inside the bacterial cytoplasm. Since the discovery of quorum sensing, it was established that the production of virulence factors by bacteria is tightly growth-phase regulated. It is now obvious that expression of bacterial virulence is also controlled by detection of the eukaryotic messengers released in the micro-environment as endocrine or neuro-endocrine modulators. In the presence of host physiological stress many eukaryotic factors are released and detected by Gram-negative bacteria which in return rapidly adapt their physiology. For instance, Pseudomonas aeruginosa can bind elements of the host immune system such as interferon-? and dynorphin and then through quorum sensing circuitry enhance its virulence. Escherichia coli sensitivity to the neurohormones of the catecholamines family appears relayed by a recently identified bacterial adrenergic receptor. In the present review, we will describe the mechanisms by which various eukaryotic signal molecules produced by host may activate Gram-negative bacteria virulence. Particular attention will be paid to Pseudomonas, a genus whose representative species, P. aeruginosa, is a common opportunistic pathogen. The discussion will be particularly focused on the pivotal role played by these new types of pathogen sensors from the sensing to the transduction mechanism involved in virulence factors regulation. Finally, we will discuss the consequence of the impact of host signal molecules on commensally or opportunistic pathogens associated with different human tissue. PMID:22399982

Lesouhaitier, Olivier; Veron, Wilfried; Chapalain, Annelise; Madi, Amar; Blier, Anne-Sophie; Dagorn, Audrey; Connil, Nathalie; Chevalier, Sylvie; Orange, Nicole; Feuilloley, Marc

2009-01-01

220

Retrocyclins neutralize bacterial toxins by potentiating their unfolding.  

PubMed

Defensins are a class of immune peptides with a broad range of activities against bacterial, fungal and viral pathogens. Besides exerting direct anti-microbial activity via dis-organization of bacterial membranes, defensins are also able to neutralize various unrelated bacterial toxins. Recently, we have demonstrated that in the case of human ?- and ?-defensins, this later ability is achieved through exploiting toxins' marginal thermodynamic stability, i.e. defensins act as molecular anti-chaperones unfolding toxin molecules and exposing their hydrophobic regions and thus promoting toxin precipitation and inactivation [Kudryashova et al. (2014) Immunity 41, 709-721]. Retrocyclins (RCs) are humanized synthetic ?-defensin peptides that possess unique cyclic structure, differentiating them from ?- and ?-defensins. Importantly, RCs are more potent against some bacterial and viral pathogens and more stable than their linear counterparts. However, the mechanism of bacterial toxin inactivation by RCs is not known. In the present study, we demonstrate that RCs facilitate unfolding of bacterial toxins. Using differential scanning fluorimetry (DSF), limited proteolysis and collisional quenching of internal tryptophan fluorescence, we show that hydrophobic regions of toxins normally buried in the molecule interior become more exposed to solvents and accessible to proteolytic cleavage in the presence of RCs. The RC-induced unfolding of toxins led to their precipitation and abrogated activity. Toxin inactivation by RCs was strongly diminished under reducing conditions, but preserved at physiological salt and serum concentrations. Therefore, despite significant structural diversity, ?-, ?- and ?-defensins employ similar mechanisms of toxin inactivation, which may be shared by anti-microbial peptides from other families. PMID:25670244

Kudryashova, Elena; Seveau, Stephanie; Lu, Wuyuan; Kudryashov, Dmitri S

2015-04-15

221

Diversity of Bacterial Communities of Fitness Center Surfaces in a U.S. Metropolitan Area  

PubMed Central

Public fitness centers and exercise facilities have been implicated as possible sources for transmitting community-acquired bacterial infections. However, the overall diversity of the bacterial community residing on the surfaces in these indoor environments is still unknown. In this study, we investigated the overall bacterial ecology of selected fitness centers in a metropolitan area (Memphis, TN, USA) utilizing culture-independent pyrosequencing of the 16S rRNA genes. Samples were collected from the skin-contact surfaces (e.g., exercise instruments, floor mats, handrails, etc.) within fitness centers. Taxonomical composition revealed the abundance of Firmicutes phyla, followed by Proteobacter and Actinobacteria, with a total of 17 bacterial families and 25 bacterial genera. Most of these bacterial genera are of human and environmental origin (including, air, dust, soil, and water). Additionally, we found the presence of some pathogenic or potential pathogenic bacterial genera including Salmonella, Staphylococcus, Klebsiella, and Micrococcus. Staphylococcus was found to be the most prevalent genus. Presence of viable forms of these pathogens elevates risk of exposure of any susceptible individuals. Several factors (including personal hygiene, surface cleaning and disinfection schedules of the facilities) may be the reasons for the rich bacterial diversity found in this study. The current finding underscores the need to increase public awareness on the importance of personal hygiene and sanitation for public gym users. PMID:25479039

Mukherjee, Nabanita; Dowd, Scot E.; Wise, Andy; Kedia, Sapna; Vohra, Varun; Banerjee, Pratik

2014-01-01

222

Recombinant bacterial amylopullulanases  

PubMed Central

Pullulanases are endo-acting enzymes capable of hydrolyzing ?-1, 6-glycosidic linkages in starch, pullulan, amylopectin, and related oligosaccharides, while amylopullulanases are bifunctional enzymes with an active site capable of cleaving both ?-1, 4 and ?-1, 6 linkages in starch, amylose and other oligosaccharides, and ?-1, 6 linkages in pullulan. The amylopullulanases are classified in GH13 and GH57 family enzymes based on the architecture of catalytic domain and number of conserved sequences. The enzymes with two active sites, one for the hydrolysis of ?-1, 4- glycosidic bond and the other for ?-1, 6-glycosidic bond, are called ?-amylase-pullulanases, while amylopullulanases have only one active site for cleaving both ?-1, 4- and ?-1, 6-glycosidic bonds. The amylopullulanases produced by bacteria find applications in the starch and baking industries as a catalyst for one step starch liquefaction-saccharification for making various sugar syrups, as antistaling agent in bread and as a detergent additive. PMID:23645215

Nisha, M; Satyanarayana, T

2013-01-01

223

Parents FamiliesGuide PARENT & FAMILY RESOURCES  

E-print Network

Parents FamiliesGuide #12;11 Contents: PARENT & FAMILY RESOURCES Welcome from Vice Presidents ---------- 2 Parents Program Welcome --------------- 3 Parents & Families Weekend Information ---------------------- 5 Partnering with Penn State ------------- 6 The Role of the Student ------------------- 6 Penn

Thompson, Anne

224

New Functions for the Ancient DedA Membrane Protein Family  

PubMed Central

The DedA protein family is a highly conserved and ancient family of membrane proteins with representatives in most sequenced genomes, including those of bacteria, archaea, and eukarya. The functions of the DedA family proteins remain obscure. However, recent genetic approaches have revealed important roles for certain bacterial DedA family members in membrane homeostasis. Bacterial DedA family mutants display such intriguing phenotypes as cell division defects, temperature sensitivity, altered membrane lipid composition, elevated envelope-related stress responses, and loss of proton motive force. The DedA family is also essential in at least two species of bacteria: Borrelia burgdorferi and Escherichia coli. Here, we describe the phylogenetic distribution of the family and summarize recent progress toward understanding the functions of the DedA membrane protein family. PMID:23086209

Sikdar, Rakesh; Kumar, Sujeet; Boughner, Lisa A.

2013-01-01

225

NLRP3 Inflammasome and Host Protection against Bacterial Infection  

PubMed Central

The inflammasome is a multi-protein complex that induces maturation of inflammatory cytokines interleukin (IL)-1? and IL-18 through activation of caspase-1. Several nucleotide binding oligomerization domain-like receptor family members, including NLRP3, recognize unique microbial and danger components and play a central role in inflammasome activation. The NLRP3 inflammasome is critical for maintenance of homeostasis against pathogenic infections. However, inflammasome activation acts as a double-edged sword for various bacterial infections. When the IL-1 family of cytokines is secreted excessively, they cause tissue damage and extensive inflammatory responses that are potentially hazardous for the host. Emerging evidence has shown that diverse bacterial pathogens or their components negatively regulate inflammasome activation to escape the immune response. In this review, we discuss the current knowledge of the roles and regulation of the NLRP3 inflammasome during bacterial infections. Activation and regulation of the NLRP3 inflammasome should be tightly controlled to prevent virulence and pathology during infections. Understanding the roles and regulatory mechanisms of the NLRP3 inflammasome is essential for developing potential treatment approaches against pathogenic infections. PMID:24133343

Kim, Jwa-Jin

2013-01-01

226

Bacterial killing via a type IV secretion system.  

PubMed

Type IV secretion systems (T4SSs) are multiprotein complexes that transport effector proteins and protein-DNA complexes through bacterial membranes to the extracellular milieu or directly into the cytoplasm of other cells. Many bacteria of the family Xanthomonadaceae, which occupy diverse environmental niches, carry a T4SS with unknown function but with several characteristics that distinguishes it from other T4SSs. Here we show that the Xanthomonas citri T4SS provides these cells the capacity to kill other Gram-negative bacterial species in a contact-dependent manner. The secretion of one type IV bacterial effector protein is shown to require a conserved C-terminal domain and its bacteriolytic activity is neutralized by a cognate immunity protein whose 3D structure is similar to peptidoglycan hydrolase inhibitors. This is the first demonstration of the involvement of a T4SS in bacterial killing and points to this special class of T4SS as a mediator of both antagonistic and cooperative interbacterial interactions. PMID:25743609

Souza, Diorge P; Oka, Gabriel U; Alvarez-Martinez, Cristina E; Bisson-Filho, Alexandre W; Dunger, German; Hobeika, Lise; Cavalcante, Nayara S; Alegria, Marcos C; Barbosa, Leandro R S; Salinas, Roberto K; Guzzo, Cristiane R; Farah, Chuck S

2015-01-01

227

Pathogenicity Islands in Bacterial Pathogenesis  

PubMed Central

In this review, we focus on a group of mobile genetic elements designated pathogenicity islands (PAI). These elements play a pivotal role in the virulence of bacterial pathogens of humans and are also essential for virulence in pathogens of animals and plants. Characteristic molecular features of PAI of important human pathogens and their role in pathogenesis are described. The availability of a large number of genome sequences of pathogenic bacteria and their benign relatives currently offers a unique opportunity for the identification of novel pathogen-specific genomic islands. However, this knowledge has to be complemented by improved model systems for the analysis of virulence functions of bacterial pathogens. PAI apparently have been acquired during the speciation of pathogens from their nonpathogenic or environmental ancestors. The acquisition of PAI not only is an ancient evolutionary event that led to the appearance of bacterial pathogens on a timescale of millions of years but also may represent a mechanism that contributes to the appearance of new pathogens within a human life span. The acquisition of knowledge about PAI, their structure, their mobility, and the pathogenicity factors they encode not only is helpful in gaining a better understanding of bacterial evolution and interactions of pathogens with eukaryotic host cells but also may have important practical implications such as providing delivery systems for vaccination, tools for cell biology, and tools for the development of new strategies for therapy of bacterial infections. PMID:14726454

Schmidt, Herbert; Hensel, Michael

2004-01-01

228

Taxonomy of bacterial fish pathogens  

PubMed Central

Bacterial taxonomy has progressed from reliance on highly artificial culture-dependent techniques involving the study of phenotype (including morphological, biochemical and physiological data) to the modern applications of molecular biology, most recently 16S rRNA gene sequencing, which gives an insight into evolutionary pathways (= phylogenetics). The latter is applicable to culture-independent approaches, and has led directly to the recognition of new uncultured bacterial groups, i.e. "Candidatus", which have been associated as the cause of some fish diseases, including rainbow trout summer enteritic syndrome. One immediate benefit is that 16S rRNA gene sequencing has led to increased confidence in the accuracy of names allocated to bacterial pathogens. This is in marked contrast to the previous dominance of phenotyping, and identifications, which have been subsequently challenged in the light of 16S rRNA gene sequencing. To date, there has been some fluidity over the names of bacterial fish pathogens, with some, for example Vibrio anguillarum, being divided into two separate entities (V. anguillarum and V. ordalii). Others have been combined, for example V. carchariae, V. harveyi and V. trachuri as V. harveyi. Confusion may result with some organisms recognized by more than one name; V. anguillarum was reclassified as Beneckea and Listonella, with Vibrio and Listonella persisting in the scientific literature. Notwithstanding, modern methods have permitted real progress in the understanding of the taxonomic relationships of many bacterial fish pathogens. PMID:21314902

2011-01-01

229

New Treatments for Bacterial Keratitis  

PubMed Central

Purpose. To review the newer treatments for bacterial keratitis. Data Sources. PubMed literature search up to April 2012. Study Selection. Key words used for literature search: “infectious keratitis”, “microbial keratitis”, “infective keratitis”, “new treatments for infectious keratitis”, “fourth generation fluoroquinolones”, “moxifloxacin”, “gatifloxacin”, “collagen cross-linking”, and “photodynamic therapy”. Data Extraction. Over 2400 articles were retrieved. Large scale studies or publications at more recent dates were selected. Data Synthesis. Broad spectrum antibiotics have been the main stay of treatment for bacterial keratitis but with the emergence of bacterial resistance; there is a need for newer antimicrobial agents and treatment methods. Fourth-generation fluoroquinolones and corneal collagen cross-linking are amongst the new treatments. In vitro studies and prospective clinical trials have shown that fourth-generation fluoroquinolones are better than the older generation fluoroquinolones and are as potent as combined fortified antibiotics against common pathogens that cause bacterial keratitis. Collagen cross-linking was shown to improve healing of infectious corneal ulcer in treatment-resistant cases or as an adjunct to antibiotics treatment. Conclusion. Fourth-generation fluoroquinolones are good alternatives to standard treatment of bacterial keratitis using combined fortified topical antibiotics. Collagen cross-linking may be considered in treatment-resistant infectious keratitis or as an adjunct to antibiotics therapy. PMID:22991650

Wong, Raymond L. M.; Gangwani, R. A.; Yu, Lester W. H.; Lai, Jimmy S. M.

2012-01-01

230

Roles within the Family  

MedlinePLUS

... family unit, and which rights, privileges, obligations, and roles are assigned to each family member. In most families parents are expected to be the leaders or executives of the family; children are expected to follow the ...

231

Single Parent Families  

MedlinePLUS

... Families > Single Parent Families Family Life Listen Single Parent Families Article Body Single parenthood can be one ... in the United States live with only one parent. Most single-parent situations result from divorce, but ...

232

DEPLOYMENT & THE MILITARY FAMILY  

E-print Network

1 DEPLOYMENT & THE MILITARY FAMILY NEW ORLEANS, LOUISIANA ACTIVE DUTY MILITARY FAMILY MEMBERS: THE FLEET AND FAMILY SUPPORT CENTER ................. 3 II. POINTS OF CONTACT (POC).............................................................................................. 3 III. HEALTH & MENTAL HEALTH RESOURCES FOR IMMEDIATE FAMILY MEMBERS OF ACTIVE DUTY MILITARY

233

Families Experiencing Homelessness  

MedlinePLUS

... which may compound the stress the family feels. Families experiencing homelessness: Are typically comprised of a mother ... of other women. The Relationship Between Homelessness and Family Separation: Families who have experienced homelessness have much ...

234

eCAMBer: efficient support for large-scale comparative analysis of multiple bacterial strains  

PubMed Central

Background Inconsistencies are often observed in the genome annotations of bacterial strains. Moreover, these inconsistencies are often not reflected by sequence discrepancies, but are caused by wrongly annotated gene starts as well as mis-identified gene presence. Thus, tools are needed for improving annotation consistency and accuracy among sets of bacterial strain genomes. Results We have developed eCAMBer, a tool for efficiently supporting comparative analysis of multiple bacterial strains within the same species. eCAMBer is a highly optimized revision of our earlier tool, CAMBer, scaling it up for significantly larger datasets comprising hundreds of bacterial strains. eCAMBer works in two phases. First, it transfers gene annotations among all considered bacterial strains. In this phase, it also identifies homologous gene families and annotation inconsistencies. Second, eCAMBer, tries to improve the quality of annotations by resolving the gene start inconsistencies and filtering out gene families arising from annotation errors propagated in the previous phase. Conculsions eCAMBer efficiently identifies and resolves annotation inconsistencies among closely related bacterial genomes. It outperforms other competing tools both in terms of running time and accuracy of produced annotations. Software, user manual, and case study results are available at the project website: http://bioputer.mimuw.edu.pl/ecamber. PMID:24597904

2014-01-01

235

Abdominal radiation causes bacterial translocation  

SciTech Connect

The purpose of this study was to determine if a single dose of radiation to the rat abdomen leads to bacterial translocation into the mesenteric lymph nodes (MLN). A second issue addressed was whether translocation correlates with anatomic damage to the mucosa. The radiated group (1100 cGy) which received anesthesia also was compared with a control group and a third group which received anesthesia alone but no abdominal radiation. Abdominal radiation lead to 100% positive cultures of MLN between 12 hr and 4 days postradiation. Bacterial translocation was almost nonexistent in the control and anesthesia group. Signs of inflammation and ulceration of the intestinal mucosa were not seen until Day 3 postradiation. Mucosal damage was maximal by Day 4. Bacterial translocation onto the MLN after a single dose of abdominal radiation was not apparently dependent on anatomical, histologic damage of the mucosa.

Guzman-Stein, G.; Bonsack, M.; Liberty, J.; Delaney, J.P.

1989-02-01

236

Bacterial Degradation of Aromatic Compounds  

PubMed Central

Aromatic compounds are among the most prevalent and persistent pollutants in the environment. Petroleum-contaminated soil and sediment commonly contain a mixture of polycyclic aromatic hydrocarbons (PAHs) and heterocyclic aromatics. Aromatics derived from industrial activities often have functional groups such as alkyls, halogens and nitro groups. Biodegradation is a major mechanism of removal of organic pollutants from a contaminated site. This review focuses on bacterial degradation pathways of selected aromatic compounds. Catabolic pathways of naphthalene, fluorene, phenanthrene, fluoranthene, pyrene, and benzo[a]pyrene are described in detail. Bacterial catabolism of the heterocycles dibenzofuran, carbazole, dibenzothiophene, and dibenzodioxin is discussed. Bacterial catabolism of alkylated PAHs is summarized, followed by a brief discussion of proteomics and metabolomics as powerful tools for elucidation of biodegradation mechanisms. PMID:19440284

Seo, Jong-Su; Keum, Young-Soo; Li, Qing X.

2009-01-01

237

Bacterial toxins: friends or foes?  

PubMed Central

Many emerging and reemerging bacterial pathogens synthesize toxins that serve as primary virulence factors. We highlight seven bacterial toxins produced by well-established or newly emergent pathogenic microbes. These toxins, which affect eukaryotic cells by a variety of means, include Staphylococcus aureus alpha-toxin, Shiga toxin, cytotoxic necrotizing factor type 1, Escherichia coli heat-stable toxin, botulinum and tetanus neurotoxins, and S. aureus toxic-shock syndrome toxin. For each, we discuss the information available on its synthesis and structure, mode of action, and contribution to virulence. We also review the role certain toxins have played in unraveling signal pathways in eukaryotic cells and summarize the beneficial uses of toxins and toxoids. Our intent is to illustrate the importance of the analysis of bacterial toxins to both basic and applied sciences. PMID:10221874

Schmitt, C. K.; Meysick, K. C.; O'Brien, A. D.

1999-01-01

238

Bacterial thermotaxis by speed modulation  

NASA Astrophysics Data System (ADS)

One of the most important factors that affects bacterial migration and is sensitive to thermal changes is the bacterial swimming speed controlled by the rotation of the flagellar motors. In the natural habitats of bacteria, gradients often extend over relatively long distances such that their steepness is too small for bacteria to detect. We studied the bacterial behavior in such thermal gradients and found that they migrate along shallow thermal gradients due to a change in their swimming speed resulting from the effect of temperature on the intracellular pH. When nutrients are scarce the bacteria's intracellular pH and consequently the swimming speed decreases with increasing temperature, which causes them to drift towards the warm end of the gradient. However, when serine is added to the medium at concentrations >300microM, the intracellular pH increases causing the swimming speed to increase continuously with increasing temperature, and the bacteria to drift towards the cold end of the gradient. This directional migration is not a result of bacterial thermotaxis in the classical sense, because the steepness of the gradients is below the sensing threshold of bacteria. Nevertheless, our results show that the directional switch requires the presence of the bacterial sensing receptors which seem to be involved in regulating the intracellular pH. Additionally, it is also important to understand how thermal fluctuations and rate of thermal changes experienced by bacteria during their excursion in natural environments affect their run speed. To this end we have studied the dynamics of the bacterial flagellar motor's speed in response to thermal fluctuations by tethering bacteria to a glass surface through their flagella. Our results show that under heavy load the response of the motor to fast linear thermal changes is instantaneous. However, when subjected to thermal fluctuations with varying frequency, they exhibit a resonant response to specific frequencies reflecting the complex internal dynamics of the motor.

Demir, Mahmut

239

Positive Family Functioning.  

ERIC Educational Resources Information Center

The persistence of the nuclear family as the primary social unit in the United States and most all other societies, especially complex ones, is a fact. Values shape the definition of family, especially the "good family," and the "great debate" of this period on family failure, family corruption and the family's near demise originates in…

Sussman, Marvin B.

240

Reclaiming Family Privilege  

ERIC Educational Resources Information Center

The pull for family is strong, almost primeval, most likely it is evolutionary, and for those lacking the benefit of family or Family Privilege, the loss of family is painful and profoundly sad. Young people who struggle to cope without stable family connections are profoundly aware of their lack of "Family Privilege." In this article, the author…

Seita, John

2012-01-01

241

Curved microchannels and bacterial streamers  

NASA Astrophysics Data System (ADS)

Bacterial biofilms are commonly identified as microbial communities attached to a surface and encased in a self-secreted extracellular matrix. Due to their increased resistance to antimicrobial agents, biofilms have an enormous impact on health and medicine (e.g., wound healing, implant-associated infections, disease transmission). On the other hand, they constitute a major component of the stream ecosystem by increasing transport of nutrients and retention of suspended particles. In this talk, we present an experimental study of bacterial biofilm development in a microfluidic device. In particular, we show the formation of filamentous structures, or streamers, in curved channels and how these suspended biofilms are linked to the underlying hydrodynamics.

Rusconi, Roberto; Lecuyer, Sigolene; Guglielmini, Laura; Stone, Howard

2010-03-01

242

FMLA: Family & Medical FLA: Family Leave Act  

E-print Network

FMLA: Family & Medical Leave Act FLA: Family Leave Act DVL: Domestic Violence Leave Faculty Sick Leave FCAL: Family Care Act Leave Parental Leave & Leave Without Salary Who is · Faculty (9 month calendar weeks during one academic year (26 calendar weeks if eligible for "Service Member Family Leave

Borenstein, Elhanan

243

A Novel Bacterial Mucinase, Glycosulfatase, Is Associated with Bacterial Vaginosis  

Microsoft Academic Search

The modifications to the vaginal habitat accompanying a change to vaginal flora in bacterial vaginosis (BV) are poorly understood. In this study enzymes involved in mucin degradation were measured, including a novel glycosulfatase assay. Women attending an emergency walk-in sexually transmitted disease clinic were studied. One high vaginal swab (HVS) was used to prepare a gram-stained smear to determine BV

Anthony M. Roberton; Rebecca Wiggins; Patrick J. Horner; Rosemary Greenwood; Theresa Crowley; Arnold Fernandes; Monica Berry; Anthony P. Corfield

244

Bacterial Communities of Diverse Drosophila Species: Ecological Context of a Host–Microbe Model System  

PubMed Central

Drosophila melanogaster is emerging as an important model of non-pathogenic host–microbe interactions. The genetic and experimental tractability of Drosophila has led to significant gains in our understanding of animal–microbial symbiosis. However, the full implications of these results cannot be appreciated without the knowledge of the microbial communities associated with natural Drosophila populations. In particular, it is not clear whether laboratory cultures can serve as an accurate model of host–microbe interactions that occur in the wild, or those that have occurred over evolutionary time. To fill this gap, we characterized natural bacterial communities associated with 14 species of Drosophila and related genera collected from distant geographic locations. To represent the ecological diversity of Drosophilids, examined species included fruit-, flower-, mushroom-, and cactus-feeders. In parallel, wild host populations were compared to laboratory strains, and controlled experiments were performed to assess the importance of host species and diet in shaping bacterial microbiome composition. We find that Drosophilid flies have taxonomically restricted bacterial communities, with 85% of the natural bacterial microbiome composed of only four bacterial families. The dominant bacterial taxa are widespread and found in many different host species despite the taxonomic, ecological, and geographic diversity of their hosts. Both natural surveys and laboratory experiments indicate that host diet plays a major role in shaping the Drosophila bacterial microbiome. Despite this, the internal bacterial microbiome represents only a highly reduced subset of the external bacterial communities, suggesting that the host exercises some level of control over the bacteria that inhabit its digestive tract. Finally, we show that laboratory strains provide only a limited model of natural host–microbe interactions. Bacterial taxa used in experimental studies are rare or absent in wild Drosophila populations, while the most abundant associates of natural Drosophila populations are rare in the lab. PMID:21966276

Bhatnagar, Srijak; Eisen, Jonathan A.; Kopp, Artyom

2011-01-01

245

A Cross-Taxon Analysis of Insect-Associated Bacterial Diversity  

PubMed Central

Although it is well known that plants and animals harbor microbial symbionts that can influence host traits, the factors regulating the structure of these microbial communities often remain largely undetermined. This is particularly true for insect-associated microbial communities, as few cross-taxon comparisons have been conducted to date. To address this knowledge gap and determine how host phylogeny and ecology affect insect-associated microbial communities, we collected 137 insect specimens representing 39 species, 28 families, and 8 orders, and characterized the bacterial communities associated with each specimen via 16S rRNA gene sequencing. Bacterial taxa within the phylum Proteobacteria were dominant in nearly all insects sampled. On average, the insect-associated bacterial communities were not very diverse, with individuals typically harboring fewer than 8 bacterial phylotypes. Bacterial communities also tended to be dominated by a single phylotype; on average, the most abundant phylotype represented 54.7% of community membership. Bacterial communities were significantly more similar among closely related insects than among less-related insects, a pattern driven by within-species community similarity but detected at every level of insect taxonomy tested. Diet was a poor predictor of bacterial community composition. Individual insect species harbored remarkably unique communities: the distribution of 69.0% of bacterial phylotypes was limited to unique insect species, whereas only 5.7% of phylotypes were detected in more than five insect species. Together these results suggest that host characteristics strongly regulate the colonization and assembly of bacterial communities across insect lineages, patterns that are driven either by co-evolution between insects and their symbionts or by closely related insects sharing conserved traits that directly select for similar bacterial communities. PMID:23613815

Jones, Ryan Thomas; Sanchez, Leticia Gonzales; Fierer, Noah

2013-01-01

246

Mapping of QTL for bacterial cold water disease resistance in rainbow trout  

Technology Transfer Automated Retrieval System (TEKTRAN)

Bacterial cold water disease (BCWD) causes significant economic loss in salmonid aquaculture. We previously detected genetic variation in survival following challenge with Flavobacterium psychrophilum, the causative agent of BCWD in rainbow trout, and a family-based selection program to improve res...

247

An insight into the origin and functional evolution of bacterial aromatic ring-hydroxylating oxygenases  

Microsoft Academic Search

Bacterial aromatic ring-hydroxylating oxygenases (RHOs) are multicomponent enzyme systems which have potential utility in bioremediation of aromatic compounds in the environment. To cope with the enormous diversity of aromatic compounds in the environment, this enzyme family has evolved remarkably exhibiting broad substrate specificity. RHOs are multicomponent enzymes comprising of a homo- or hetero-multimeric terminal oxygenase and one or more electron

Joydeep Chakraborty; Debajyoti Ghosal; Arindam Dutta; Tapan K. Dutta

2012-01-01

248

Response to selection for bacterial cold water disease resistance in rainbow trout  

Technology Transfer Automated Retrieval System (TEKTRAN)

A family-based selection program was initiated at the National Center for Cool and Cold Water Aquaculture in 2005 to improve resistance to bacterial cold water disease (BCWD) in rainbow trout. The objective of this study was to estimate response to 2 generations of selection. A total of 14,841 juven...

249

Mapping of QTL for bacterial cold water disease resistance in rainbow trout  

Technology Transfer Automated Retrieval System (TEKTRAN)

Bacterial cold water disease (BCWD) causes significant economic loss in salmonid aquaculture. We previously detected genetic variation in survival following challenge with Flavobacterium psychrophilum (Fp), the causative agent of BCWD in rainbow trout, and a family-based selection program to improv...

250

Antibiotic resistance of bacterial strains isolated from children in Child Health Center, Warsaw  

Microsoft Academic Search

This study examines the antibiotic susceptibility of 1792 bacterial strains isolated from hospitalized children between January and December 1993. A total of 1015 Gram-negative rods represented by members of Enterobacteriaceae family (770) and nonfermenters (245) were isolated. The most resistant strains were noticed among Klebsiella pneumoniae and Enterobacter cloacae. From 38% to 46% of K. pneumoniae strains were resistant to

D. Dzier?anowska; U. ?opaciuk; W. Kami?ska; J. Wieczy?ska; A. Pawi?ska; J. Patzer

1995-01-01

251

Development of an engineered ‘bioluminescent’ reporter phage for the detection of bacterial blight of crucifers  

Technology Transfer Automated Retrieval System (TEKTRAN)

Bacterial blight, caused by the phytopathogen Pseudomonas cannabina pv. alisalensis, is an emerging disease afflicting important members of the Brassica family. The disease is often misdiagnosed as peppery leaf spot, a much less severe disease caused by the closely related pathogen Pseudomonas syrin...

252

Bacterial endosymbiont infections in 'living fossils': a case study of North American vaejovid scorpions.  

PubMed

Bacterial endosymbionts are common among arthropods, and maternally inherited forms can affect the reproductive and behavioural traits of their arthropod hosts. The prevalence of bacterial endosymbionts and their role in scorpion evolution have rarely been investigated. In this study, 61 samples from 40 species of scorpion in the family Vaejovidae were screened for the presence of the bacterial endosymbionts Cardinium, Rickettsia, Spiroplasma and Wolbachia. No samples were infected by these bacteria. However, one primer pair specifically designed to amplify Rickettsia amplified nontarget genes of other taxa. Similar off-target amplification using another endosymbiont-specific primer was also found during preliminary screenings. Results caution against the overreliance on previously published screening primers to detect bacterial endosymbionts in host taxa and suggest that primer specificity may be higher in primers targeting nuclear rather than mitochondrial genes. PMID:24373187

Bryson, Robert W

2014-07-01

253

The protective role of endogenous bacterial communities in chironomid egg masses and larvae  

PubMed Central

Insects of the family Chironomidae, also known as chironomids, are distributed worldwide in a variety of water habitats. These insects display a wide range of tolerance toward metals and organic pollutions. Bacterial species known for their ability to degrade toxicants were identified from chironomid egg masses, leading to the hypothesis that bacteria may contribute to the survival of chironomids in polluted environments. To gain a better understanding of the bacterial communities that inhabit chironomids, the endogenous bacteria of egg masses and larvae were studied by 454-pyrosequencing. The microbial community of the egg masses was distinct from that of the larval stage, most likely due to the presence of one dominant bacterial Firmicutes taxon, which consisted of 28% of the total sequence reads from the larvae. This taxon may be an insect symbiont. The bacterial communities of both the egg masses and the larvae were found to include operational taxonomic units, which were closely related to species known as toxicant degraders. Furthermore, various bacterial species with the ability to detoxify metals were isolated from egg masses and larvae. Koch-like postulates were applied to demonstrate that chironomid endogenous bacterial species protect the insect from toxic heavy metals. We conclude that chironomids, which are considered pollution tolerant, are inhabited by stable endogenous bacterial communities that have a role in protecting their hosts from toxicants. This phenomenon, in which bacteria enable the continued existence of their host in hostile environments, may not be restricted only to chironomids. PMID:23804150

Senderovich, Yigal; Halpern, Malka

2013-01-01

254

Distinct antimicrobial peptide expression determines host species-specific bacterial associations.  

PubMed

Animals are colonized by coevolved bacterial communities, which contribute to the host's health. This commensal microbiota is often highly specific to its host-species, inferring strong selective pressures on the associated microbes. Several factors, including diet, mucus composition, and the immune system have been proposed as putative determinants of host-associated bacterial communities. Here we report that species-specific antimicrobial peptides account for different bacterial communities associated with closely related species of the cnidarian Hydra. Gene family extensions for potent antimicrobial peptides, the arminins, were detected in four Hydra species, with each species possessing a unique composition and expression profile of arminins. For functional analysis, we inoculated arminin-deficient and control polyps with bacterial consortia characteristic for different Hydra species and compared their selective preferences by 454 pyrosequencing of the bacterial microbiota. In contrast to control polyps, arminin-deficient polyps displayed decreased potential to select for bacterial communities resembling their native microbiota. This finding indicates that species-specific antimicrobial peptides shape species-specific bacterial associations. PMID:24003149

Franzenburg, Sören; Walter, Jonas; Künzel, Sven; Wang, Jun; Baines, John F; Bosch, Thomas C G; Fraune, Sebastian

2013-09-24

255

Distinct antimicrobial peptide expression determines host species-specific bacterial associations  

PubMed Central

Animals are colonized by coevolved bacterial communities, which contribute to the host’s health. This commensal microbiota is often highly specific to its host-species, inferring strong selective pressures on the associated microbes. Several factors, including diet, mucus composition, and the immune system have been proposed as putative determinants of host-associated bacterial communities. Here we report that species-specific antimicrobial peptides account for different bacterial communities associated with closely related species of the cnidarian Hydra. Gene family extensions for potent antimicrobial peptides, the arminins, were detected in four Hydra species, with each species possessing a unique composition and expression profile of arminins. For functional analysis, we inoculated arminin-deficient and control polyps with bacterial consortia characteristic for different Hydra species and compared their selective preferences by 454 pyrosequencing of the bacterial microbiota. In contrast to control polyps, arminin-deficient polyps displayed decreased potential to select for bacterial communities resembling their native microbiota. This finding indicates that species-specific antimicrobial peptides shape species-specific bacterial associations. PMID:24003149

Franzenburg, Sören; Walter, Jonas; Künzel, Sven; Wang, Jun; Baines, John F.; Bosch, Thomas C. G.; Fraune, Sebastian

2013-01-01

256

Therapy of Bacterial Fish Diseases  

Microsoft Academic Search

During the past decade considerable progress has been made in the therapy of bacterial fish diseases. This progress was possible largely because of the introduction of powerful chemotherapeutic agents such as sulfonamides and antibiotics.Fish furunculosis can be treated with very good results with sulfamerazine, sulfamethazine, and sulfaguanidine as well as by chloramphenicol and terramycin. Ulcer disease caused by Hemophilus piscium

S. F. Snieszko

1954-01-01

257

Tyrosine phosphorylation and bacterial virulence  

PubMed Central

Protein phosphorylation on tyrosine has emerged as a key device in the control of numerous cellular functions in bacteria. In this article, we review the structure and function of bacterial tyrosine kinases and phosphatases. Phosphorylation is catalyzed by autophosphorylating adenosine triphosphate-dependent enzymes (bacterial tyrosine (BY) kinases) that are characterized by the presence of Walker motifs. The reverse reaction is catalyzed by three classes of enzymes: the eukaryotic-like phosphatases (PTPs) and dual-specific phosphatases; the low molecular weight protein-tyrosine phosphatases (LMW-PTPs); and the polymerase–histidinol phosphatases (PHP). Many BY kinases and tyrosine phosphatases can utilize host cell proteins as substrates, thereby contributing to bacterial pathogenicity. Bacterial tyrosine phosphorylation/dephosphorylation is also involved in biofilm formation and community development. The Porphyromonas gingivalis tyrosine phosphatase Ltp1 is involved in a restraint pathway that regulates heterotypic community development with Streptococcus gordonii. Ltp1 is upregulated by contact with S. gordonii and Ltp1 activity controls adhesin expression and levels of the interspecies signal AI-2. PMID:22388693

Whitmore, Sarah E; Lamont, Richard J

2012-01-01

258

Bacterial Growth H. L. Smith  

E-print Network

. Exercise 1 The gut bacteria E. coli can divide every thirty minutes when nutrients are abundantBacterial Growth H. L. Smith 1 Simple Models Bacteria are the dominant form of life on the planet but a source of sustenance for bacteria. Humans have learned to harness bacteria and other microbes to produce

Smith, Hal

259

Disease notes - Bacterial root rot  

Technology Transfer Automated Retrieval System (TEKTRAN)

Bacterial root rot initiated by lactic acid bacteria, particularly Leuconostoc, occurs every year in Idaho sugarbeet fields. Hot fall weather seems to make the problem worse. Although Leuconostoc initiates the rot, other bacteria and yeast frequently invade the tissue as well. The acetic acid bac...

260

Mutation discovery in bacterial genomes  

E-print Network

, a gastric pathogen implicated in peptic ulcer disease and gastric cancer4,5. H. pylori infections are oftenMutation discovery in bacterial genomes: metronidazole resistance in Helicobacter pylori Thomas J it to study metronidazole resistance in H. pylori. CGS identified mutations in several genes, most likely

Cai, Long

261

Prostatitis- bacterial - self-care  

MedlinePLUS

You have been diagnosed with bacterial prostatitis . This is an infection that involves the prostate gland. ... If you have acute prostatitis, your symptoms started quickly. You may still feel ill, with fever, chills, and flushing. It may hurt a lot when ...

262

Multiple Forms of Bacterial Hydrogenases  

PubMed Central

Ackrell, B. A. C. (University of Hawaii, Honolulu), R. N. Asato, and H. F. Mower. Multiple forms of bacterial hydrogenases. J. Bacteriol. 92:828–838. 1966.—Extracts of certain bacterial species have been shown by disc electrophoresis on polyacrylamide gel to contain multiple hydrogenase systems. The hydrogenase enzymes comprising these systems have different electrophoretic mobilities and produce a band pattern that is unique for each bacterial species. Of 20 bacterial species known to possess hydrogenase activity and which were examined by this technique, only the activities of Clostridium tetanomorphum and C. thermosaccharolyticum could be attributed, at pH 8.3, to a single hydrogenase enzyme. This multiplicity of hydrogenase forms was found both in bacteria which contain mostly soluble hydrogenases and in those where the hydrogenase is predominantly associated with particulate material. When solubilization of this particulate material could be effected, at least two solubilized hydrogenases were released, and, of these, one would have the same electrophoretic properties (i.e., RF) as one of the soluble hydrogenases already present in small amounts within the cell. Different growth conditions for various types of bacteria, such as the nitrogen source, the degree of aeration, and photosynthetic versus aerobic growth in the dark, as well as the conditions under which the cells were stored, markedly affected the hydrogenase activity of the cells, but not their hydrogenase band pattern. The disc electrophoresis technique proved to be 10 times more sensitive than the manometric technique in detecting hydrogenase activity. PMID:5926752

Ackrell, B. A. C.; Asato, R. N.; Mower, H. F.

1966-01-01

263

BACTERIAL INHIBITORS IN LAKE WATER  

EPA Science Inventory

The populations of six bacterial genera fell rapidly after their addition to sterile lake water but not after their addition to buffer. The decline in numbers of two species that were studied further, Klebsiella pneumoniae and Micrococcus flavus, occurred even when the buffer was...

264

Bacterial Transformation (Chemically Competent Cells)  

E-print Network

'-30'. 5) Heat shock at 42o C for EXACTLY 45". Do not exceed 45". 6) Allow cells to recover on wet iceBacterial Transformation (Chemically Competent Cells) Leslie Vosshall 1/22/2001 1) Retrieve transformation. Once thawed, aliquots cannot be re-frozen, so discard extra cell volume if you are only

265

Bacterial kidney disease (Renibacterium salmoninarum)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Bacterial kidney disease (BKD), caused by Renibacterium salmoninarum, is a prevalent disease of salmonid fish that impacts sustainable production for consumption and species conservation efforts. The disease is chronic in nature and mortality most often occurs in juvenile salmonids and prespawning a...

266

Bacterial infection after liver transplantation  

PubMed Central

Infectious complications are major causes of morbidity and mortality after liver transplantation, despite recent advances in the transplant field. Bacteria, fungi, viruses and parasites can cause infection before and after transplantation. Among them, bacterial infections are predominant during the first two months post-transplantation and affect patient and graft survival. They might cause surgical site infections, including deep intra-abdominal infections, bacteremia, pneumonia, catheter-related infections and urinary tract infections. The risk factors for bacterial infections differ between the periods after transplant, and between centers. Recently, the emergence of multi-drug resistant bacteria is great concern in liver transplant (LT) patients. The instructive data about effects of infections with extended-spectrum beta lactamase producing bacteria, carbapenem-resistant gram-negative bacteria, and glycopeptide-resistant gram-positive bacteria were reported on a center-by-center basis. To prevent post-transplant bacterial infections, proper strategies need to be established based upon center-specific data and evidence from well-controlled studies. This article reviewed the recent epidemiological data, risk factors for each type of infections and important clinical issues in bacterial infection after LT. PMID:24876741

Kim, Sang Il

2014-01-01

267

Quorum sensing and bacterial cooperation Anand Pai  

E-print Network

Quorum sensing and bacterial cooperation Anand Pai CTMS Graduate Fellow of cooperation benefits bacteria. Fig. 1: Schematic of bacterial communication The equation depicts the dynamics of population density N under logistic growth. Its

Wolpert, Robert L

268

SIMPLAS: A Simulation of Bacterial Plasmid Maintenance.  

ERIC Educational Resources Information Center

This article describes a computer simulation of bacterial physiology during growth in a chemostat. The program was designed to help students to appreciate and understand the related effects of parameters which influence plasmid persistence in bacterial populations. (CW)

Dunn, A.; And Others

1988-01-01

269

What is Bacterial Vaginosis? Bacterial Vaginosis (BV) is the most common kind of  

E-print Network

What is Bacterial Vaginosis? Bacterial Vaginosis (BV) is the most common kind of vaginal infection) often have BV in conjunction with the STI. BACTERIAL VAGINOSIS IS NOT A YEAST INFECTION Many women have of alcohol in many liquid medications may cause nausea and vomiting if taking metronidazole. BACTERIAL

Virginia Tech

270

Molecular target of synthetic antimicrobial oligomer in bacterial membranes  

NASA Astrophysics Data System (ADS)

Antimicrobial peptides comprises a key component of innate immunity for a wide range of multicellular organisms. It has been shown that natural antimicrobial peptides and their synthetic analogs have demonstrated broad-spectrum antimicrobial activity via permeating bacterial membranes selectively. Synthetic antimicrobials with tunable structure and toxicological profiles are ideal for investigations of selectivity mechanisms. We investigate interactions and self-assembly using a prototypical family of antimicrobials based on phenylene ethynylene. Results from synchrotron small angle x-ray scattering (SAXS) results and in vitro microbicidal assays on genetically modified `knock-out' bacteria will be presented.

Yang, Lihua; Gordon, Vernita; Som, Abhigyan; Cronan, John; Tew, Gregory; Wong, Gerard

2008-03-01

271

Familial Hypercholesterolaemia  

PubMed Central

Familial hypercholesterolaemia (FH), defined as the heritable occurrence of severe hypercholesterolaemia with cholesterol deposits in tendons and premature heart disease, is caused by at least four genes in sterol and lipoprotein pathways and displays varying gene-dose effects. The genes are the low-density lipoprotein (LDL) receptor, apolipoprotein (apo) B, proprotein convertase subtilisin/kexin 9, and the autosomal recessive hypercholesterolaemia (ARH) adaptor protein. All of these disorders have in common defective clearance of LDL within a complex system of lipid and lipoprotein metabolism and regulation. Normal cellular cholesterol and lipoprotein metabolism is reviewed before describing the disorders, their metabolic derangements and their clinical effects. FH is classified as two simplified phenotypes of disease according to the severity of the metabolic derangement. The dominantly inherited heterozygous phenotype comprises defects in the LDL receptor, apoB100, and neural apoptosis regulatory cleavage protein. The homozygous phenotype is co-dominant in defects of the LDL receptor, and occurs also as the ARH of adapter protein mutations. Defective binding of apoB100 does not result in a significant gene dose effect, but enhances the severity of heterozygotes for LDL receptor mutations. The genetic diagnosis of FH has provided greater accuracy in definition and detection of disease and exposes information about migration of populations. All of these disorders pose a high risk of atherosclerosis, especially in the homozygous phenotype. Studies of influences on the phenotype and responses to treatment are also discussed in the context of the metabolic derangements. PMID:18516203

Marais, A David

2004-01-01

272

BACTERIAL GROWTH EFFICIENCY IN NATURAL AQUATIC SYSTEMS  

Microsoft Academic Search

Heterotrophic bacteria perform two major functions in the transformation of or- ganic matter: They produce new bacterial biomass (bacterial secondary produc- tion (BP)), and they respire organic C to inorganic C (bacterial respiration (BR)). For planktonic bacteria, a great deal has been learned about BP and its regulation during the past several decades but far less has been learned about

Paul A. del Giorgio; Jonathan J. Cole

1998-01-01

273

Bacterial Growth on Allochthonous Carbon in Humic  

E-print Network

Bacterial Growth on Allochthonous Carbon in Humic and Nutrient-enriched Lakes: Results from Whole biomass con- sisted of 43­46% allochthonous C. In Tuesday Lake more than 75% of bacterial growth the relative importance of autochtho- nous and allochthonous C in supporting bacterial production. For 35 days

Pace, Michael L.

274

Mast Cells in Bacterial Infections Elin Rnnberg  

E-print Network

Mast Cells in Bacterial Infections Elin Rönnberg Faculty of Veterinary Medicine and Animal Science-91-576-8010-5 © 2014 Elin Rönnberg, Uppsala Print: SLU Service/Repro, Uppsala 2014 #12;Mast Cells in Bacterial Infections Abstract Mast cells are implicated in immunity towards bacterial infection, but the molecular

275

Resistance to Bacterial Pathogens in Plants  

E-print Network

). Disease symptoms caused by bacterial pathogens include wilts, galls, specks, spots, cankers and chlorosis in causing soft-rot diseases in- duced by bacteria in the Erwinia genus. Basal Defence against BacterialResistance to Bacterial Pathogens in Plants Jules Ade, Indiana University, Bloomington, Indiana

Innes, Roger

276

Delayed infection, family size and malignant lymphomas  

PubMed Central

BACKGROUND—The annual incidence of non-Hodgkin's lymphomas (NHL) is increasing by 3%-4% in different parts of the developed world. Excesses of NHL have been observed in populations exposed to immunosuppressants and to HIV, but these causes do not explain the increasing trends. It is suggested that delayed infection could explain NHL trends, through an impairment of the Th1/Th2 lymphocyte patterns.?METHODS—In a population-based study on 1388 patients with NHL, 354 with Hodgkin's disease (HD) and 1718 healthy controls, the age of first occurrence of bacterial and viral diseases was investigated. Clinical records were perused in one centre to check the anamnestic data.?FINDINGS—The age of occurrence of bacterial and viral diseases was significantly higher among NHL patients than in the controls. The association between later age at first bacterial or viral disease was limited to small families (OR= 1.95; 95% confidence intervals 1.26, 3.00, for age 4-8 at first infection; OR=1.91; 1.19, 3.06, for age 9+, compared with less than 4). The association was more obvious for bacterial diseases (possibly for the lower degree of misclassification). High grade lymphomas showed the strongest association. The later age of occurrence of bacterial or viral diseases in NHL patients is consistent with a higher incidence of lymphomas observed in higher social groups. No clear association was found between HD and age at first bacterial or viral diseases.?INTERPRETATION—It is proposed that delayed infection could explain the increasing NHL trends, through an impairment of the Th1/Th2 lymphocyte patterns. The model of delayed infection has been proposed also to explain increasing prevalence rates of asthma.?? PMID:11076986

Vineis, P; Miligi, L; Crosignani, P; Fontana, A; Masala, G; Nanni, O; Ramazzotti, V; Rodella, S; Stagnaro, E; Tumino, R; Vigano, C; Vindigni, C; Costantini, A

2000-01-01

277

Family and family therapy in Russia.  

PubMed

This article represents the information about family and family therapy in the context of culture, traditions and contemporary changes of social situations in Russia. The legislation of family rights are mentioned within items about marriage and family in the Constitution, Civil Code and Family Code of the Russian Federation which has changed during recent years. The definition of family and description of family structure are given through the prism of the current demographic situation, dynamics of statistics of marriage and divorce rates, mental disorders, disabilities and such phenomena as social abandonment. The actual curriculum, teaching of family therapy and its disadvantages, system of continuous education, supervision and initiatives of the Institute of Integrative Family Therapy in improvement of preparing of specialists who can provide qualified psychosocial assistance for the family according to the actual needs of society are noted. The directions of state and private practice of family counselling and therapy both for psychiatric patients and medical patients, for adults and children in a family systemic approach are highlighted with an indication of the spectrum of techniques and methods used by Russian professionals. The main obstacles and perspectives of development of family therapy in Russia are summarized. PMID:22515460

Bebtschuk, Marina; Smirnova, Daria; Khayretdinov, Oleg

2012-04-01

278

Families with Gifted Adolescents  

ERIC Educational Resources Information Center

Studies of families with gifted adolescents have revealed conflicting results. Adolescents, mothers, and fathers of 84 families with a gifted adolescent and of 95 families with a non-gifted adolescent evaluated their family system independently. Dependent variables were cohesion, democratic family style (adaptability), organisation, achievement…

Schilling, Susanne R.; Sparfeldt, Jorn; Rost, Detlef H.

2006-01-01

279

The Changing Family Structure.  

ERIC Educational Resources Information Center

This newsletter issue contains feature articles and short reports on how and why family structures are undergoing substantial change in many parts of the world. These articles include: (1) "The Changing Family Structure," a review of how families are changing and why; (2) "Peru: Families in the Andes"; (3) "Thailand: Families of the Garbage Dump";…

Bernard van Leer Foundation Newsletter, 1993

1993-01-01

280

Family Treatment Unit.  

ERIC Educational Resources Information Center

The document describes the Family Treatment Unit, a demonstration program to provide a variety of family treatment services to status offenders (11 to 17 years old) and their families. The goals of the program are: (1) to provide family services to families of status offenders; (2) to maintain status offenders in their natural homes by…

Sawicki, Donna

281

Boston University Family Medicine  

E-print Network

Boston University Family Medicine Global Health CollaborativeFamily Medicine As part of the Department of Family Medicine at Boston University, the Collaborative is committed to introducing and improving Family Medicine programs around the world. Family Medicine is a holistic specialty that attends

Spence, Harlan Ernest

282

Family Reading Night  

ERIC Educational Resources Information Center

This book offers clear and practical guidelines to help engage families in student success. It shows families how to conduct a successful Family Reading Night at their school. Family Night themes include Scary Stories, Books We Love, Reading Olympics, Dr. Seuss, and other themes. Family reading nights invite parents to come to school with their…

Hutchins, Darcy; Greenfeld, Marsha; Epstein, Joyce

2007-01-01

283

The truncated nuclear family  

Microsoft Academic Search

The truncated nuclear family is defined: it is the garden-variety family “pathology” found. The critical role of polarized continuity and discontinuity values in producing the truncated nuclear family is discussed. There is a brief review of factors in American society which, over the decades since the Second World War, have evolved the nuclear family as a dominant family unit, and

Gerald H. Zuk

1985-01-01

284

Inhibitors of bacterial tubulin target bacterial membranes in vivo.  

PubMed

FtsZ is a homolog of eukaryotic tubulin that is widely conserved among bacteria and coordinates the assembly of the cell division machinery. FtsZ plays a central role in cell replication and is a target of interest for antibiotic development. Several FtsZ inhibitors have been reported. We characterized the mechanism of these compounds in bacteria and found that many of them disrupt the localization of membrane-associated proteins, including FtsZ, by reducing the transmembrane potential or perturbing membrane permeability. We tested whether the reported phenotypes of a broad collection of FtsZ inhibitors disrupt the transmembrane potential in Bacillus subtilis strain 168. Using a combination of flow cytometry and microscopy, we found that zantrin Z1, cinnamaldehyde, totarol, sanguinarine, and viriditoxin decreased the B. subtilis transmembrane potential or perturbed membrane permeability, and influenced the localization of the membrane-associated, division protein MinD. These studies demonstrate that small molecules that disrupt membrane function in bacterial cells produce phenotypes that are similar to the inhibition of proteins associated with membranes in vivo, including bacterial cytoskeleton homologs, such as FtsZ. The results provide a new dimension for consideration in the design and testing of inhibitors of bacterial targets that are membrane-associated and provide additional insight into the structural characteristics of antibiotics that disrupt the membrane. PMID:23539337

Foss, Marie H; Eun, Ye-Jin; Grove, Charles I; Pauw, Daniel A; Sorto, Nohemy A; Rensvold, Jarred W; Pagliarini, David J; Shaw, Jared T; Weibel, Douglas B

2013-01-01

285

Relationships between host phylogeny, host type and bacterial community diversity in cold-water coral reef sponges.  

PubMed

Cold-water coral reefs are known to locally enhance the diversity of deep-sea fauna as well as of microbes. Sponges are among the most diverse faunal groups in these ecosystems, and many of them host large abundances of microbes in their tissues. In this study, twelve sponge species from three cold-water coral reefs off Norway were investigated for the relationship between sponge phylogenetic classification (species and family level), as well as sponge type (high versus low microbial abundance), and the diversity of sponge-associated bacterial communities, taking also geographic location and water depth into account. Community analysis by Automated Ribosomal Intergenic Spacer Analysis (ARISA) showed that as many as 345 (79%) of the 437 different bacterial operational taxonomic units (OTUs) detected in the dataset were shared between sponges and sediments, while only 70 (16%) appeared purely sponge-associated. Furthermore, changes in bacterial community structure were significantly related to sponge species (63% of explained community variation), sponge family (52%) or sponge type (30%), whereas mesoscale geographic distances and water depth showed comparatively small effects (<5% each). In addition, a highly significant, positive relationship between bacterial community dissimilarity and sponge phylogenetic distance was observed within the ancient family of the Geodiidae. Overall, the high diversity of sponges in cold-water coral reefs, combined with the observed sponge-related variation in bacterial community structure, support the idea that sponges represent heterogeneous, yet structured microbial habitats that contribute significantly to enhancing bacterial diversity in deep-sea ecosystems. PMID:23393586

Schöttner, Sandra; Hoffmann, Friederike; Cárdenas, Paco; Rapp, Hans Tore; Boetius, Antje; Ramette, Alban

2013-01-01

286

Bacterial cheating limits antibiotic resistance  

NASA Astrophysics Data System (ADS)

The widespread use of antibiotics has led to the evolution of resistance in bacteria. Bacteria can gain resistance to the antibiotic ampicillin by acquiring a plasmid carrying the gene beta-lactamase, which inactivates the antibiotic. This inactivation may represent a cooperative behavior, as the entire bacterial population benefits from removing the antibiotic. The cooperative nature of this growth suggests that a cheater strain---which does not contribute to breaking down the antibiotic---may be able to take advantage of cells cooperatively inactivating the antibiotic. Here we find experimentally that a ``sensitive'' bacterial strain lacking the plasmid conferring resistance can invade a population of resistant bacteria, even in antibiotic concentrations that should kill the sensitive strain. We observe stable coexistence between the two strains and find that a simple model successfully explains the behavior as a function of antibiotic concentration and cell density. We anticipate that our results will provide insight into the evolutionary origin of phenotypic diversity and cooperative behaviors.

Xiao Chao, Hui; Yurtsev, Eugene; Datta, Manoshi; Artemova, Tanya; Gore, Jeff

2012-02-01

287

Bacterial contamination of amniotic membrane  

PubMed Central

AIM—In the light of interest being shown in amniotic membrane grafts for use in ocular surgery, this study aims to identify the bacterial contaminants commonly found on placental membranes from both caesarean and vaginal deliveries.?METHODS—Samples of placental membrane were taken following both elective caesarean and normal vaginal deliveries. Bacterial contaminants were identified.?RESULTS—All samples were contaminated. A greater number of different species were recovered from the vaginal deliveries, including several which were actually or potentially pathogenic.?CONCLUSION—There is a greater risk of contamination from pathogenic bacteria on placentas from vaginal deliveries. It is recommended that amnion for use in ocular surface procedures should be retrieved only from placentas following elective caesarean deliveries.?? PMID:11159493

Adds, P.; Hunt, C.; Hartley, S.

2001-01-01

288

Functional Taxonomy of Bacterial Hyperstructures  

PubMed Central

The levels of organization that exist in bacteria extend from macromolecules to populations. Evidence that there is also a level of organization intermediate between the macromolecule and the bacterial cell is accumulating. This is the level of hyperstructures. Here, we review a variety of spatially extended structures, complexes, and assemblies that might be termed hyperstructures. These include ribosomal or “nucleolar” hyperstructures; transertion hyperstructures; putative phosphotransferase system and glycolytic hyperstructures; chemosignaling and flagellar hyperstructures; DNA repair hyperstructures; cytoskeletal hyperstructures based on EF-Tu, FtsZ, and MreB; and cell cycle hyperstructures responsible for DNA replication, sequestration of newly replicated origins, segregation, compaction, and division. We propose principles for classifying these hyperstructures and finally illustrate how thinking in terms of hyperstructures may lead to a different vision of the bacterial cell. PMID:17347523

Norris, Vic; den Blaauwen, Tanneke; Cabin-Flaman, Armelle; Doi, Roy H.; Harshey, Rasika; Janniere, Laurent; Jimenez-Sanchez, Alfonso; Jin, Ding Jun; Levin, Petra Anne; Mileykovskaya, Eugenia; Minsky, Abraham; Saier, Milton; Skarstad, Kirsten

2007-01-01

289

Autophagy and bacterial infectious diseases  

PubMed Central

Autophagy is a housekeeping process that maintains cellular homeostasis through recycling of nutrients and degradation of damaged or aged cytoplasmic constituents. Over the past several years, accumulating evidence has suggested that autophagy can function as an intracellular innate defense pathway in response to infection with a variety of bacteria and viruses. Autophagy plays a role as a specialized immunologic effector and regulates innate immunity to exert antimicrobial defense mechanisms. Numerous bacterial pathogens have developed the ability to invade host cells or to subvert host autophagy to establish a persistent infection. In this review, we have summarized the recent advances in our understanding of the interaction between antibacterial autophagy (xenophagy) and different bacterial pathogens. PMID:22257885

Yuk, Jae-Min; Yoshimori, Tamotsu

2012-01-01

290

Electromagnetic Signals from Bacterial DNA  

E-print Network

Chemical reactions can be induced at a distance due to the propagation of electromagnetic signals during intermediate chemical stages. Although is is well known at optical frequencies, e.g. photosynthetic reactions, electromagnetic signals hold true for muck lower frequencies. In E. coli bacteria such electromagnetic signals can be generated by electric transitions between energy levels describing electrons moving around DNA loops. The electromagnetic signals between different bacteria within a community is a "wireless" version of intercellular communication found in bacterial communities connected by "nanowires". The wireless broadcasts can in principle be of both the AM and FM variety due to the magnetic flux periodicity in electron energy spectra in bacterial DNA orbital motions.

A. Widom; J. Swain; Y. N. Srivastava; S. Sivasubramanian

2012-02-09

291

Family Research and Family Therapy: A Reunion?  

ERIC Educational Resources Information Center

Identifies several of the most important forms of recent and current family research and family therapy that are important to clinicians. Suggests that the reunion of clinical and research interests signifies a new growth of the family therapy field. (Author/JAC)

Wynne, Lyman C.

1983-01-01

292

Family Capital: Implications for Interventions with Families  

ERIC Educational Resources Information Center

Social capital has been extensively discussed in the literature as building blocks that individuals and communities utilize to leverage system resources. Similarly, some families also create capital, which can enable members of the family, such as children, to successfully negotiate the outside world. Families in poverty confront serious…

Belcher, John R.; Peckuonis, Edward V.; Deforge, Bruce R.

2011-01-01

293

Importance of Family Routines  

MedlinePLUS

... Pediatric First Aid for Caregivers and Teachers (PedFACTs) Teaching Package First Aid for Families (PedFACTs) Allergies and Asthma Family Life Health Management - Medical Home Family Dynamics Adoption & Foster Care Communication & Discipline Types ...

294

Family Reunion Health Guide  

MedlinePLUS

... HEALTH GUIDE 1. Send a Kidney Health Message Hi Family, I came across this information and thought ... mails to family members. Before the Reunion 1. Hi family! Taking care of your kidneys is important. ...

295

Graduate School INTERNATIONAL FAMILY  

E-print Network

Graduate School Graduate School INTERNATIONAL FAMILY AND COMMUNITY STUDIES Doctor of Philosophy Certificate the doctoral program in International Family and community Studies educates professionals to generate, diffuse, and apply knowledge needed to strengthen communities' capacity for family support

Stuart, Steven J.

296

Choosing a Family Doctor  

MedlinePLUS

... do? Family doctors take care of the physical, mental and emotional health of both their patients and their patients' families. They know your family's health history and how it can affect you. They are ...

297

Media Time Family Pledge  

MedlinePLUS

... Media Time Family Pledge Family Life Listen Media Time Family Pledge Article Body At the beginning and ... them. Kids learn best with small lessons over time as opposed to one big lecture or sit- ...

298

About Familial Pulmonary Fibrosis  

MedlinePLUS

About Familial Pulmonary Fibrosis An estimated 10-15 percent of patients with idiopathic pulmonary fibrosis (IPF) have a form of the pulmonary fibrosis that runs in families. This is called Familial ...

299

Functional Bacterial Amyloids in Biofilms  

Microsoft Academic Search

\\u000a Functional bacterial amyloids constitute a group of important proteinaceous surface structures. Most amyloids are highly insoluble\\u000a in water and resistant to most enzymes and thermal and chemical denaturants. Their functions in bacteria are still not well\\u000a described but seem to include fimbriae and other cell appendages for adhesion and biofilm formation, cell envelope components,\\u000a spore coating, formation of large extracellular

Per Halkjær Nielsen; Morten Simonsen Dueholm; Trine Rolighed Thomsen; Jeppe Lund Nielsen; Daniel Otzen

300

Identification of bacterial guanylate cyclases.  

PubMed

The ability of bacteria to use cGMP as a second messenger has been controversial for decades. Recently, nucleotide cyclases from Rhodospirillum centenum, GcyA, and Xanthomonas campestris, GuaX, have been shown to possess guanylate cyclase activities. Enzymatic activities of these guanylate cyclases measured in vitro were low, which makes interpretation of the assays ambiguous. Protein sequence analysis at present is insufficient to distinguish between bacterial adenylate and guanylate cyclases, both of which belong to nucleotide cyclases of type III. We developed a simple method for discriminating between guanylate and adenylate cyclase activities in a physiologically relevant bacterial system. The method relies on the use of a mutant cAMP receptor protein, CRPG , constructed here. While wild-type CRP is activated exclusively by cAMP, CRPG can be activated by either cAMP or cGMP. Using CRP- and CRPG -dependent lacZ expression in two E. coli strains, we verified that R. centenum GcyA and X. campestris GuaX have primarily guanylate cyclase activities. Among two other bacterial nucleotide cyclases tested, one, GuaA from Azospillrillum sp. B510, proved to have guanylate cyclase activity, while the other one, Bradyrhizobium japonicum CyaA, turned out to function as an adenylate cyclase. The results obtained with this reporter system were in excellent agreement with direct measurements of cyclic nucleotides secreted by E. coli expressing nucleotide cyclase genes. The simple genetic screen developed here is expected to facilitate identification of bacterial guanylate cyclases and engineering of guanylate cyclases with desired properties. Proteins 2015; 83:799-804. © 2015 Wiley Periodicals, Inc. PMID:25645367

Ryu, Min-Hyung; Youn, Hwan; Kang, In-Hye; Gomelsky, Mark

2015-05-01

301

Information Processing in Bacterial Chemotaxis  

NSDL National Science Digital Library

Motile bacteria respond to attractants and repellents in their environment by changing their movement. Stock et al. describe the similarities of the bacterial chemotaxis signaling system to eukaryotic signaling cascades. Also included is a discussion of how the ordered signaling complex of the receptor, the kinase CheA, and the kinase regulator CheW can be thought of as a primitive "probrain" to allow the integration of signals to produce the optimal cellular response.

Jeffry B. Stock (Princeton University; Department of Molecular Biology REV)

2002-05-14

302

Protein Secretion in Bacterial Cells  

Microsoft Academic Search

Approximately 20% of the proteins synthesized in a bacterial cell are transported outside of the cytoplasm. These proteins\\u000a are localized either within the different compartments of the cell envelope or are released into the extracellular growth\\u000a medium. Bacteria have evolved multiple pathways to secrete proteins across their cell envelopes. In this chapter, we examine\\u000a similarities and differences among the several

Christos Stathopoulos; Yihfen T. Yen; Casey Tsang; Todd Cameron

303

Vaginal immunity in bacterial vaginosis  

Microsoft Academic Search

Vaginal immunity in response to microbial perturbation is still poorly understood and may be crucial for protection from adverse\\u000a outcomes associated with bacterial vaginosis (BV). BV is the most prevalent vaginal disorder in adult women worldwide. However,\\u000a its pathogenesis is still elusive. In BVpositive women, inflammatory signs are scant—approximately 50% of women are asymptomatic.\\u000a The number of vaginal neutrophils in

Sabina Cauci

2004-01-01

304

Bacterial Contamination of Blood Components  

PubMed Central

Blood for transfusion is a potential source of infection by a variety of known and unknown transmissible agents. Over the last 20 years, astounding reductions in the risk of viral infection via allogeneic blood have been achieved. As a result of this success, bacterial contamination of blood products has emerged as the greatest residual source of transfusion-transmitted disease. This paper summarizes the current status of detection, prevention, and elimination of bacteria in blood products for transfusion. PMID:15653826

Brecher, Mark E.; Hay, Shauna N.

2005-01-01

305

Bacterial motion in narrow capillaries.  

PubMed

Motile bacteria often have to pass through small tortuous pores in soil or tissue of higher organisms. However, their motion in this prevalent type of niche is not fully understood. Here, we modeled it with narrow glass capillaries and identified a critical radius (Rc) for bacterial motion. Near the surface of capillaries narrower than that, the swimming trajectories are helices. In larger capillaries, they swim in distorted circles. Under non-slip condition, the peritrichous Escherichia coli swam in left-handed helices with an Rc of ?10 ?m near glass surface. However, slipping could occur in the fast monotrichous Pseudomonas fluorescens, when a speed threshold was exceeded, and thus both left-handed and right-handed helices were executed in glass capillaries. In the natural non-cylindrical pores, the near-surface trajectories would be spirals and twisted loops. Engaging in such motions reduces the bacterial migration rate. With a given pore size, the run length and the tumbling angle of the bacterium determine the probability and duration of their near-surface motion. Shear flow and chemotaxis potentially enhance it. Based on this observation, the puzzling previous observations on bacterial migration in porous environments can be interpreted. PMID:25764548

Ping, Liyan; Wasnik, Vaibhav; Emberly, Eldon

2015-02-01

306

Mechanism of Bacterial Pyrite Oxidation  

PubMed Central

The oxidation by Ferrobacillus ferrooxidans of untreated pyrite (FeS2) as well as HCl-pretreated pyrite (from which most of the acid-soluble iron species were removed) was studied manometrically. Oxygen uptake was linear during bacterial oxidation of untreated pyrite, whereas with HCl-pretreated pyrite both a decrease in oxygen uptake at 2 hr and nonlinear oxygen consumption were observed. Ferric sulfate added to HCl-pretreated pyrite restored approximately two-thirds of the decrease in total bacterial oxygen uptake and caused oxygen uptake to revert to nearly linear kinetics. Ferric sulfate also oxidized pyrite in the absence of bacteria and O2; recovery of ferric and ferrous ions was in excellent agreement with the reaction Fe2(SO4)3 + FeS2 = 3FeSO4 + 2S, but the elemental sulfur produced was negligible. Neither H2S nor S2O32? was a product of the reaction. It is probable that two mechanisms of bacterial pyrite oxidation operate concurrently: the direct contact mechanism which requires physical contact between bacteria and pyrite particles for biological pyrite oxidation, and the indirect contact mechanism according to which the bacteria oxidize ferrous ions to the ferric state, thereby regenerating the ferric ions required for chemical oxidation of pyrite. PMID:6051342

Silverman, Melvin P.

1967-01-01

307

Phylogenetic mapping of bacterial morphology  

NASA Technical Reports Server (NTRS)

The availability of a meaningful molecular phylogeny for bacteria provides a context for examining the historical significance of various developments in bacterial evolution. Herein, the classical morphological descriptions of selected members of the domain Bacteria are mapped upon the genealogical ancestry deduced from comparison of small-subunit rRNA sequences. For the species examined in this study, a distinct pattern emerges which indicates that the coccus shape has arisen and accumulated independently multiple times in separate lineages and typically survived as a persistent end-state morphology. At least two other morphologies persist but have evolved only once. This study demonstrates that although bacterial morphology is not useful in defining bacterial phylogeny, it is remarkably consistent with that phylogeny once it is known. An examination of the experimental evidence available for morphogenesis as well as microbial fossil evidence corroborates these findings. It is proposed that the accumulation of persistent morphologies is a result of the biophysical properties of peptidoglycan and their genetic control, and that an evolved body-plan strategy based on peptidoglycan may have been a fate-sealing step in the evolution of Bacteria. More generally, this study illustrates that significant evolutionary insights can be obtained by examining biological and biochemical data in the context of a reliable phylogenetic structure.

Siefert, J. L.; Fox, G. E.

1998-01-01

308

Dialkylresorcinols as bacterial signaling molecules.  

PubMed

It is well recognized that bacteria communicate via small diffusible molecules, a process termed quorum sensing. The best understood quorum sensing systems are those that use acylated homoserine lactones (AHLs) for communication. The prototype of those systems consists of a LuxI-like AHL synthase and a cognate LuxR receptor that detects the signal. However, many proteobacteria possess LuxR receptors, yet lack any LuxI-type synthase, and thus these receptors are referred to as LuxR orphans or solos. In addition to the well-known AHLs, little is known about the signaling molecules that are sensed by LuxR solos. Here, we describe a novel cell-cell communication system in the insect and human pathogen Photorhabdus asymbiotica. We identified the LuxR homolog PauR to sense dialkylresorcinols (DARs) and cyclohexanediones (CHDs) instead of AHLs as signals. The DarABC synthesis pathway produces the molecules, and the entire system emerged as important for virulence. Moreover, we have analyzed more than 90 different Photorhabdus strains by HPLC/MS and showed that these DARs and CHDs are specific to the human pathogen P. asymbiotica. On the basis of genomic evidence, 116 other bacterial species are putative DAR producers, among them many human pathogens. Therefore, we discuss the possibility of DARs as novel and widespread bacterial signaling molecules and show that bacterial cell-cell communication goes far beyond AHL signaling in nature. PMID:25550519

Brameyer, Sophie; Kresovic, Darko; Bode, Helge B; Heermann, Ralf

2015-01-13

309

Physics of the Bacterial Chromosome  

NASA Astrophysics Data System (ADS)

Genomic DNA in bacteria is concentrated in a distinct structure, the bacterial chromosome or nucleoid [Pettijohn, D.E. (1996) The Nucleoid. In Neidhardt, F.C., Curtis III, R., Ingraham, J.L., Lin, E.C.C., Low, K.B., Magasanik, B., Reznikoff, W.S., Riley, M., Schaechter, M. and Umbarger, H.E. (eds.), Escherichia coli and Salmonella. ASM Press, Washington D.C., pp. 158-166; Trun, N.J. and Marko, J.F. (1998) Architecture of a bacterial chromosome. Am. Soc. Microbiol. Rev., 64, 276-283]. Stripped of all bound proteins and RNA being produced during transcription and then stretched, the length of the DNA is circa 1.5 mm, a factor of about a thousandfold larger than typical bacterial dimensions. Thus, bacteria, like all living organisms, face the daunting challenge of compacting their genome to fit inside the cell in such a way that the information encoded in the DNA will be accessible for gene expression and replication of the genome. In the case of bacteria, members of the prokaryote world (cells without a nucleus), natural selection resulted in three mechanisms that act together to compact the genome and produce a functional, dynamic architecture: supercoiling, macromolecular crowding, and the association of the DNA with a class of nucleoid-associated or histone-like proteins. I will now describe briefly these mechanisms.

Stavans, Joel

2006-01-01

310

Detergent-compatible bacterial amylases.  

PubMed

Proteases, lipases, amylases, and cellulases are enzymes used in detergent formulation to improve the detergency. The amylases are specifically supplemented to the detergent to digest starchy stains. Most of the solid and liquid detergents that are currently manufactured contain alkaline enzymes. The advantages of using alkaline enzymes in the detergent formulation are that they aid in removing tough stains and the process is environmentally friendly since they reduce the use of toxic detergent ingredients. Amylases active at low temperature are preferred as the energy consumption gets reduced, and the whole process becomes cost-effective. Most microbial alkaline amylases are used as detergent ingredients. Various reviews report on the production, purification, characterization, and application of amylases in different industry sectors, but there is no specific review on bacterial or fungal alkaline amylases or detergent-compatible amylases. In this mini-review, an overview on the production and property studies of the detergent bacterial amylases is given, and the stability and compatibility of the alkaline bacterial amylases in the presence of the detergents and the detergent components are highlighted. PMID:25129040

Niyonzima, Francois N; More, Sunil S

2014-10-01

311

Diversity of aquatic bacterial populations  

SciTech Connect

A study was designed to evaluate the feasibility of adapting the automated Quantum II for the identification of bacterial fish pathogens. Optimal incubation conditions were determined for each of the species used, and, by using a Chi-square goodness of fit test, it was shown that isolates could be sorted into like-species groups with a Ward's hierarchical cluster analysis technique. In a second study, population profiles, growth kinetics, and transformation kinetics were evaluated for bacteria isolated from 4 aquatic environments located in the southeastern United States. Gradual long-term accumulation of organic acids in the waters of the Okefenokee Swamp, located in southeast Georgia and northeast Florida, has resulted in acidic water ranging from pH 3.5 to 4.5. A study was designed to evaluate the metabolic efficiency of surface-water gram-negative nonfermentative bacteria and ascertain whether aquatic bacterial populations exhibit adaptation to the low pH conditions. Using the computerized AMBIS the uptake and incorporation of {sup 35}S-methionine into bacterial proteins under 5 levels of pH was quantitated for each of the test organisms.

Teska, J.D.

1988-01-01

312

Sulfate decomposition by bacterial leaching  

SciTech Connect

Sulfate disposal is the main problem of many industrial effluents, such as excess sulfuric acid, gypsum, coal desulfurization byproducts, acid-mine waters, and general metallurgical effluents. It has been established that sulfate present in wastes can be converted to elemental sulfur by bacterial mutualism. This study presents the results of an investigation of the industrial feasibility of utilizing a biological system capable of converting hydrous calcium sulfate (gypsum) to elemental sulfur. Gypsum, which was used in this study, is a byproduct of the fertilizer industry. The biological system is referred to as a bacterial mutualism, and involves Desulfovibrio desulfuricans for sulfate conversion and Chlorobium thiosulfatophilum for hydrogen sulfide conversion. Bacterial mutualism and utilization of sulfate were investigated by means of a two-stage anaerobic system. In the first stage, a gas purge system was used for sulfate conversion to sulfide, and it was found that maximum conversion is 34%. In the second stage, a static culture system was used for sulfide conversion to sulfur with a conversion of 92%. 14 refs., 5 tabs.

Deveci, N.; Delaloglu, C.G. [Istanbul Technical Univ. (Turkey)

1995-04-01

313

Antimicrobial peptide LL-37 promotes bacterial phagocytosis by human macrophages.  

PubMed

LL-37/hCAP-18 is the only human member of the cathelicidin family and plays an important role in killing various pathogens, as well as in immune modulation. In this study, we investigated the effect of LL-37 on bacterial phagocytosis by macrophages and demonstrate that LL-37 enhances phagocytosis of IgG-opsonized Gram-negative and Gram-positive bacteria in a dose- and time-dependent manner by dTHP-1 cells. In addition, LL-37 enhanced phagocytosis of nonopsonized Escherichia coli by human macrophages. Consistently, LL-37 elevated the expression of Fc?Rs on macrophages but not the complement receptors CD11b and -c. Further studies revealed that the expression of TLR4 and CD14 is also increased on LL-37-treated macrophages. Several lines of evidence indicated that the FPR2/ALX receptor mediated LL-37-induced phagocytosis. However, TLR4 signaling was also coupled to the phagocytic response, as a specific TLR4 antibody significantly suppressed phagocytosis of IgG-opsonized E. coli and nonopsonized E. coli by dTHP-1 cells. Finally, macrophages from Cnlp(-/-) mice exhibited diminished bacterial phagocytosis compared with macrophages from their WT littermates. In conclusion, we demonstrate a novel, immune-modulatory mechanism of LL-37, which may contribute to bacterial clearance. PMID:24550523

Wan, Min; van der Does, Anne M; Tang, Xiao; Lindbom, Lennart; Agerberth, Birgitta; Haeggström, Jesper Z

2014-06-01

314

Three computational tools for predicting bacterial essential genes.  

PubMed

Essential genes are those genes indispensable for the survival of any living cell. Bacterial essential genes constitute the cornerstones of synthetic biology and are often attractive targets in the development of antibiotics and vaccines. Because identification of essential genes with wet-lab ways often means expensive economic costs and tremendous labor, scientists changed to seek for alternative way of computational prediction. Aiming to help to solve this issue, our research group (CEFG: group of Computational, Comparative, Evolutionary and Functional Genomics, http://cefg.uestc.edu.cn) has constructed three online services to predict essential genes in bacterial genomes. These freely available tools are applicable for single gene sequences without annotated functions, single genes with definite names, and complete genomes of bacterial strains. To ensure reliable predictions, the investigated species should belong to the same family (for EGP) or phylum (for CEG_Match and Geptop) with one of the reference species, respectively. As the pilot software for the issue, predicting accuracies of them have been assessed and compared with existing algorithms, and note that all of other published algorithms have not any formed online services. We hope these services at CEFG will help scientists and researchers in the field of essential genes. PMID:25636621

Guo, Feng-Biao; Ye, Yuan-Nong; Ning, Lu-Wen; Wei, Wen

2015-01-01

315

Changing Family, Changing Education  

Microsoft Academic Search

\\u000a Sociologists of education increasingly have recognized the crucial role that families assume in children’s educational development.\\u000a Meanwhile, sociologists have identified major changes in family structure and contemporary family life—among these, increases\\u000a in the number of single-parent and step-parent families, families with older parents, and same-sex families, adoptive families,\\u000a and multiracial families. These changes have compelled sociologists of education to redirect

Laura Hamilton; Regina Werum; Lala Carr Steelman; Brian Powell

316

Surface micropattern limits bacterial contamination  

PubMed Central

Background Bacterial surface contamination contributes to transmission of nosocomial infections. Chemical cleansers used to control surface contamination are often toxic and incorrectly implemented. Additional non-toxic strategies should be combined with regular cleanings to mitigate risks of human error and further decrease rates of nosocomial infections. The Sharklet micropattern (MP), inspired by shark skin, is an effective tool for reducing bacterial load on surfaces without toxic additives. The studies presented here were carried out to investigate the MP surfaces capability to reduce colonization of methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant S. aureus (MRSA) compared to smooth control surfaces. Methods The MP and smooth surfaces produced in acrylic film were compared for remaining bacterial contamination and colonization following inoculation. Direct sampling of surfaces was carried out after inoculation by immersion, spray, and/or touch methods. Ultimately, a combination assay was developed to assess bacterial contamination after touch transfer inoculation combined with drying (persistence) to mimic common environmental contamination scenarios in the clinic or hospital environment. The combination transfer and persistence assay was then used to test antimicrobial copper beside the MP for the ability to reduce MSSA and MRSA challenge. Results The MP reduced bacterial contamination with log reductions ranging from 87-99% (LR?=?0.90-2.18; p?

2014-01-01

317

Ecology and population structure of vibrionaceae in the coastal ocean  

E-print Network

Extensive genetic diversity has been discovered in the microbial world, yet mechanisms that shape and maintain this diversity remain poorly understood. This thesis investigates to what extent populations of the ...

Preheim, Sarah Pacocha

2010-01-01

318

Family Court counselling with separating families.  

PubMed

Family Court counsellors, attached to the Family Court, see married couples who are separating, particularly those already involved, or likely to be, in Court disputes concerning their children. Children seen by the counsellors are from families in crises, and are usually detrimentally affected by family separation, and more so by any accompanying conflict. The impact on them depends on their developmental stage and position in the family system, and may be manifested in aggressive behaviour, general anxiety, psychosomatic symptoms, or manipulation and 'acting out'. The examination of the whole family system is essential to defuse the situation and thereby move the focus from the children; the close cooperation of all professionals working with the family is necessary to achieve this. PMID:7225212

Scambler, D

1980-08-01

319

Transport of Magnesium by a Bacterial Nramp-Related Gene  

PubMed Central

Magnesium is an essential divalent metal that serves many cellular functions. While most divalent cations are maintained at relatively low intracellular concentrations, magnesium is maintained at a higher level (?0.5–2.0 mM). Three families of transport proteins were previously identified for magnesium import: CorA, MgtE, and MgtA/MgtB P-type ATPases. In the current study, we find that expression of a bacterial protein unrelated to these transporters can fully restore growth to a bacterial mutant that lacks known magnesium transporters, suggesting it is a new importer for magnesium. We demonstrate that this transport activity is likely to be specific rather than resulting from substrate promiscuity because the proteins are incapable of manganese import. This magnesium transport protein is distantly related to the Nramp family of proteins, which have been shown to transport divalent cations but have never been shown to recognize magnesium. We also find gene expression of the new magnesium transporter to be controlled by a magnesium-sensing riboswitch. Importantly, we find additional examples of riboswitch-regulated homologues, suggesting that they are a frequent occurrence in bacteria. Therefore, our aggregate data discover a new and perhaps broadly important path for magnesium import and highlight how identification of riboswitch RNAs can help shed light on new, and sometimes unexpected, functions of their downstream genes. PMID:24968120

Rodionov, Dmitry A.; Freedman, Benjamin G.; Senger, Ryan S.; Winkler, Wade C.

2014-01-01

320

A microbial detection array (MDA) for viral and bacterial detection  

PubMed Central

Background Identifying the bacteria and viruses present in a complex sample is useful in disease diagnostics, product safety, environmental characterization, and research. Array-based methods have proven utility to detect in a single assay at a reasonable cost any microbe from the thousands that have been sequenced. Methods We designed a pan-Microbial Detection Array (MDA) to detect all known viruses (including phages), bacteria and plasmids and developed a novel statistical analysis method to identify mixtures of organisms from complex samples hybridized to the array. The array has broader coverage of bacterial and viral targets and is based on more recent sequence data and more probes per target than other microbial detection/discovery arrays in the literature. Family-specific probes were selected for all sequenced viral and bacterial complete genomes, segments, and plasmids. Probes were designed to tolerate some sequence variation to enable detection of divergent species with homology to sequenced organisms, and to have no significant matches to the human genome sequence. Results In blinded testing on spiked samples with single or multiple viruses, the MDA was able to correctly identify species or strains. In clinical fecal, serum, and respiratory samples, the MDA was able to detect and characterize multiple viruses, phage, and bacteria in a sample to the family and species level, as confirmed by PCR. Conclusions The MDA can be used to identify the suite of viruses and bacteria present in complex samples. PMID:21108826

2010-01-01

321

Bacterial serine/threonine protein kinases in host-pathogen interactions.  

PubMed

In bacterial pathogenesis, monitoring and adapting to the dynamically changing environment in the host and an ability to disrupt host immune responses are critical. The virulence determinants of pathogenic bacteria include the sensor/signaling proteins of the serine/threonine protein kinase (STPK) family that have a dual role of sensing the environment and subverting specific host defense processes. STPKs can sense a wide range of signals and coordinate multiple cellular processes to mount an appropriate response. Here, we review some of the well studied bacterial STPKs that are essential virulence factors and that modify global host responses during infection. PMID:24554701

Canova, Marc J; Molle, Virginie

2014-04-01

322

Avian Incubation Inhibits Growth and Diversification of Bacterial Assemblages on Eggs  

PubMed Central

Microbial infection is a critical source of mortality for early life stages of oviparous vertebrates, but parental defenses against infection are less well known. Avian incubation has been hypothesized to reduce the risk of trans-shell infection by limiting microbial growth of pathogenic bacteria on eggshells, while enhancing growth of commensal or beneficial bacteria that inhibit or competitively exclude pathogens. We tested this hypothesis by comparing bacterial assemblages on naturally incubated and experimentally unincubated eggs at laying and late incubation using a universal 16S rRNA microarray containing probes for over 8000 bacterial taxa. Before treatment, bacterial assemblages on individual eggs from both treatment groups were dissimilar to one another, as measured by clustering in non-metric dimensional scaling (NMDS) ordination space. After treatment, assemblages of unincubated eggs were similar to one another, but those of incubated eggs were not. Furthermore, assemblages of unincubated eggs were characterized by high abundance of six indicator species while incubated eggs had no indicator species. Bacterial taxon richness remained static on incubated eggs, but increased significantly on unincubated eggs, especially in several families of Gram-negative bacteria. The relative abundance of individual bacterial taxa did not change on incubated eggs, but that of 82 bacterial taxa, including some known to infect the interior of eggs, increased on unincubated eggs. Thus, incubation inhibits all of the relatively few bacteria that grow on eggshells, and does not appear to promote growth of any bacteria. PMID:19225566

Shawkey, Matthew D.; Firestone, Mary K.; Brodie, Eoin L.; Beissinger, Steven R.

2009-01-01

323

Distinct soil bacterial communities revealed under a diversely managed agroecosystem.  

PubMed

Land-use change and management practices are normally enacted to manipulate environments to improve conditions that relate to production, remediation, and accommodation. However, their effect on the soil microbial community and their subsequent influence on soil function is still difficult to quantify. Recent applications of molecular techniques to soil biology, especially the use of 16S rRNA, are helping to bridge this gap. In this study, the influence of three land-use systems within a demonstration farm were evaluated with a view to further understand how these practices may impact observed soil bacterial communities. Replicate soil samples collected from the three land-use systems (grazed pine forest, cultivated crop, and grazed pasture) on a single soil type. High throughput 16S rRNA gene pyrosequencing was used to generate sequence datasets. The different land use systems showed distinction in the structure of their bacterial communities with respect to the differences detected in cluster analysis as well as diversity indices. Specific taxa, particularly Actinobacteria, Acidobacteria, and classes of Proteobacteria, showed significant shifts across the land-use strata. Families belonging to these taxa broke with notions of copio- and oligotrphy at the class level, as many of the less abundant groups of families of Actinobacteria showed a propensity for soil environments with reduced carbon/nutrient availability. Orders Actinomycetales and Solirubrobacterales showed their highest abundance in the heavily disturbed cultivated system despite the lowest soil organic carbon (SOC) values across the site. Selected soil properties ([SOC], total nitrogen [TN], soil texture, phosphodiesterase [PD], alkaline phosphatase [APA], acid phosphatase [ACP] activity, and pH) also differed significantly across land-use regimes, with SOM, PD, and pH showing variation consistent with shifts in community structure and composition. These results suggest that use of pyrosequencing along with traditional analysis of soil physiochemical properties may provide insight into the ecology of descending taxonomic groups in bacterial communities. PMID:22844402

Shange, Raymon S; Ankumah, Ramble O; Ibekwe, Abasiofiok M; Zabawa, Robert; Dowd, Scot E

2012-01-01

324

Phylogenetically and Spatially Close Marine Sponges Harbour Divergent Bacterial Communities  

PubMed Central

Recent studies have unravelled the diversity of sponge-associated bacteria that may play essential roles in sponge health and metabolism. Nevertheless, our understanding of this microbiota remains limited to a few host species found in restricted geographical localities, and the extent to which the sponge host determines the composition of its own microbiome remains a matter of debate. We address bacterial abundance and diversity of two temperate marine sponges belonging to the Irciniidae family - Sarcotragus spinosulus and Ircinia variabilis – in the Northeast Atlantic. Epifluorescence microscopy revealed that S. spinosulus hosted significantly more prokaryotic cells than I. variabilis and that prokaryotic abundance in both species was about 4 orders of magnitude higher than in seawater. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) profiles of S. spinosulus and I. variabilis differed markedly from each other – with higher number of ribotypes observed in S. spinosulus – and from those of seawater. Four PCR-DGGE bands, two specific to S. spinosulus, one specific to I. variabilis, and one present in both sponge species, affiliated with an uncultured sponge-specific phylogenetic cluster in the order Acidimicrobiales (Actinobacteria). Two PCR-DGGE bands present exclusively in S. spinosulus fingerprints affiliated with one sponge-specific phylogenetic cluster in the phylum Chloroflexi and with sponge-derived sequences in the order Chromatiales (Gammaproteobacteria), respectively. One Alphaproteobacteria band specific to S. spinosulus was placed in an uncultured sponge-specific phylogenetic cluster with a close relationship to the genus Rhodovulum. Our results confirm the hypothesized host-specific composition of bacterial communities between phylogenetically and spatially close sponge species in the Irciniidae family, with S. spinosulus displaying higher bacterial community diversity and distinctiveness than I. variabilis. These findings suggest a pivotal host-driven effect on the shape of the marine sponge microbiome, bearing implications to our current understanding of the distribution of microbial genetic resources in the marine realm. PMID:23300853

Hardoim, Cristiane C. P.; Esteves, Ana I. S.; Pires, Francisco R.; Gonçalves, Jorge M. S.; Cox, Cymon J.; Xavier, Joana R.; Costa, Rodrigo

2012-01-01

325

Analytical solutions for bacterial energy taxis (chemotaxis): Traveling bacterial bands  

NASA Astrophysics Data System (ADS)

Motile bacteria may form bands that travel with a constant speed of propagation through a medium containing a dissolved substrate, to which they respond energy tactically. We generalize the analytical solution by Keller and Segel for such bands by accounting for (1) the presence of a porous medium, (2) substrate consumption described by a Monod kinetics model, and (3) an energy tactic response model derived by Rivero et al. Specifically, we determine the concentration profiles of the bacteria and the substrate. We also derive various expressions for the band velocity. The band velocity is also shown to equal the energy tactic velocity at the bacterial peak divided by tortuosity.

Long, Wei; Hilpert, Markus

2007-11-01

326

Attached bacterial populations shared by four species of aquatic angiosperms.  

PubMed

Symbiotic relationships between microbes and plants are common and well studied in terrestrial ecosystems, but little is known about such relationships in aquatic environments. We compared the phylogenetic diversities of leaf- and root-attached bacteria from four species of aquatic angiosperms using denaturing gradient gel electrophoresis (DGGE) and DNA sequencing of PCR-amplified 16S rRNA genes. Plants were collected from three beds in Chesapeake Bay at sites characterized as freshwater (Vallisneria americana), brackish (Potomogeton perfoliatus and Stuckenia pectinata), and marine (Zostera marina). DGGE analyses showed that bacterial communities were very similar for replicate samples of leaves from canopy-forming plants S. pectinata and P. perfoliatus and less similar for replicate samples of leaves from meadow-forming plants Z. marina and V. americana and of roots of all species. In contrast, bacterial communities differed greatly among plant species and between leaves and roots. DNA sequencing identified 154 bacterial phylotypes, most of which were restricted to single plant species. However, 12 phylotypes were found on more than one plant species, and several of these phylotypes were abundant in clone libraries and represented the darkest bands in DGGE banding patterns. Root-attached phylotypes included relatives of sulfur-oxidizing Gammaproteobacteria and sulfate-reducing Deltaproteobacteria. Leaf-attached phylotypes included relatives of polymer-degrading Bacteroidetes and phototrophic Alphaproteobacteria. Also, leaves and roots of three plant species hosted relatives of methylotrophic Betaproteobacteria belonging to the family Methylophilaceae. These results suggest that aquatic angiosperms host specialized communities of bacteria on their surfaces, including several broadly distributed and potentially mutualistic bacterial populations. PMID:18676705

Crump, Byron C; Koch, Evamaria W

2008-10-01

327

Bacterial expression of self-assembling peptide hydrogelators  

NASA Astrophysics Data System (ADS)

For tissue regeneration and drug delivery applications, various architectures are explored to serve as biomaterial tools. Via de novo design, functional peptide hydrogel materials have been developed as scaffolds for biomedical applications. The objective of this study is to investigate bacterial expression as an alternative method to chemical synthesis for the recombinant production of self-assembling peptides that can form rigid hydrogels under physiological conditions. The Schneider and Pochan Labs have designed and characterized a 20 amino acid beta-hairpin forming amphiphilic peptide containing a D-residue in its turn region (MAX1). As a result, this peptide must be prepared chemically. Peptide engineering, using the sequence of MAX1 as a template, afforded a small family of peptides for expression (EX peptides) that have different turn sequences consisting of natural amino acids and amenable to bacterial expression. Each sequence was initially chemically synthesized to quickly assess the material properties of its corresponding gel. One model peptide EX1, was chosen to start the bacterial expression studies. DNA constructs facilitating the expression of EX1 were designed in such that the peptide could be expressed with different fusion partners and subsequently cleaved by enzymatic or chemical means to afford the free peptide. Optimization studies were performed to increase the yield of pure peptide that ultimately allowed 50 mg of pure peptide to be harvested from one liter of culture, providing an alternate means to produce this hydrogel-forming peptide. Recombinant production of other self-assembling hairpins with different turn sequences was also successful using this optimized protocol. The studies demonstrate that new beta-hairpin self-assembling peptides that are amenable to bacterial production and form rigid hydrogels at physiological conditions can be designed and produced by fermentation in good yield at significantly reduced cost when compared to chemical synthesis.

Sonmez, Cem

328

Aedesin: structure and antimicrobial activity against multidrug resistant bacterial strains.  

PubMed

Multidrug resistance, which is acquired by both Gram-positive and Gram-negative bacteria, causes infections that are associated with significant morbidity and mortality in many clinical settings around the world. Because of the rapidly increasing incidence of pathogens that have become resistant to all or nearly all available antibiotics, there is a need for a new generation of antimicrobials with a broad therapeutic range for specific applications against infections. Aedesin is a cecropin-like anti-microbial peptide that was recently isolated from dengue virus-infected salivary glands of the Aedes aegypti mosquito. In the present study, we have refined the analysis of its structural characteristics and have determined its antimicrobial effects against a large panel of multidrug resistant bacterial strains, directly isolated from infected patients. Based the results from nuclear magnetic resonance spectroscopy analysis, Aedesin has a helix-bend-helix structure typical for a member of the family of ?-helix anti-microbial peptides. Aedesin efficiently killed Gram-negative bacterial strains that display the most worrisome resistance mechanisms encountered in the clinic, including resistance to carbapenems, aminoglycosides, cephalosporins, 4th generation fluoroquinolones, folate inhibitors and monobactams. In contrast, Gram-positive strains were insensitive to the lytic effects of the peptide. The anti-bacterial activity of Aedesin was found to be salt-resistant, indicating that it is active under physiological conditions encountered in body fluids characterized by ionic salt concentrations. In conclusion, because of its strong lytic activity against multidrug resistant Gram-negative bacterial strains displaying all types of clinically relevant resistance mechanisms known today, Aedesin might be an interesting candidate for the development of alternative treatment for infections caused by these types of bacteria. PMID:25162372

Godreuil, Sylvain; Leban, Nadia; Padilla, André; Hamel, Rodolphe; Luplertlop, Natthanej; Chauffour, Aurélie; Vittecoq, Marion; Hoh, François; Thomas, Frédéric; Sougakoff, Wladimir; Lionne, Corinne; Yssel, Hans; Missé, Dorothée

2014-01-01

329

Aedesin: Structure and Antimicrobial Activity against Multidrug Resistant Bacterial Strains  

PubMed Central

Multidrug resistance, which is acquired by both Gram-positive and Gram-negative bacteria, causes infections that are associated with significant morbidity and mortality in many clinical settings around the world. Because of the rapidly increasing incidence of pathogens that have become resistant to all or nearly all available antibiotics, there is a need for a new generation of antimicrobials with a broad therapeutic range for specific applications against infections. Aedesin is a cecropin-like anti-microbial peptide that was recently isolated from dengue virus-infected salivary glands of the Aedes aegypti mosquito. In the present study, we have refined the analysis of its structural characteristics and have determined its antimicrobial effects against a large panel of multidrug resistant bacterial strains, directly isolated from infected patients. Based the results from nuclear magnetic resonance spectroscopy analysis, Aedesin has a helix-bend-helix structure typical for a member of the family of ?-helix anti-microbial peptides. Aedesin efficiently killed Gram-negative bacterial strains that display the most worrisome resistance mechanisms encountered in the clinic, including resistance to carbapenems, aminoglycosides, cephalosporins, 4th generation fluoroquinolones, folate inhibitors and monobactams. In contrast, Gram-positive strains were insensitive to the lytic effects of the peptide. The anti-bacterial activity of Aedesin was found to be salt-resistant, indicating that it is active under physiological conditions encountered in body fluids characterized by ionic salt concentrations. In conclusion, because of its strong lytic activity against multidrug resistant Gram-negative bacterial strains displaying all types of clinically relevant resistance mechanisms known today, Aedesin might be an interesting candidate for the development of alternative treatment for infections caused by these types of bacteria. PMID:25162372

Padilla, André; Hamel, Rodolphe; Luplertlop, Natthanej; Chauffour, Aurélie; Vittecoq, Marion; Hoh, François; Thomas, Frédéric; Sougakoff, Wladimir; Lionne, Corinne; Yssel, Hans; Missé, Dorothée

2014-01-01

330

Changing Family Forms.  

ERIC Educational Resources Information Center

Explores the definition of family. Considers three facets of the contemporary family measured by U.S. Census statistics: (1) marriage and divorce trends; (2) declining fertility; and (3) the rise in single-headed families. Addresses the societal changes (economic, cultural, legal, and technological) that have influenced the changes in family…

Seibert, M. Therese; Willetts, Marion C.

2000-01-01

331

Families in Transition .  

ERIC Educational Resources Information Center

Focuses on disrupted families and the role of the school counselor in helping children adjust. Describes characteristics of healthy families, and discusses the transition to the blended family, effects of divorce groups on children's classroom behavior, counseling children in stepfamilies, single-parent families, and parenting strengths of single…

Bundy, Michael L., Ed.; Gumaer, James, Ed.

1984-01-01

332

THE FAMILY FLAVIVIRIDAE  

Technology Transfer Automated Retrieval System (TEKTRAN)

The family Flaviviridae, commonly referred to as the flavivirus family, contains viruses important to both human and veterinary medicine. The term flavivirus can be confusing because it is used both to refer to the family and one of the three genera within that family. The proper name of the viral...

333

Black Families. Third Edition.  

ERIC Educational Resources Information Center

The chapters of this collection explore the experiences of black families in the United States and Africa, today and in the past. They are: (1) "African American Families: A Historical Note" (John Hope Franklin); (2) "African American Families and Family Values" (Niara Sudarkasa); (3) "Old-Time Religion: Benches Can't Say 'Amen'" (William Harrison…

McAdoo, Harriette Pipes, Ed.

334

Insight into the bacterial gut microbiome of the North American moose (Alces alces)  

PubMed Central

Background The work presented here provides the first intensive insight into the bacterial populations in the digestive tract of the North American moose (Alces alces). Eight free-range moose on natural pasture were sampled, producing eight rumen samples and six colon samples. Second generation (G2) PhyloChips were used to determine the presence of hundreds of operational taxonomic units (OTUs), representing multiple closely related species/strains (>97% identity), found in the rumen and colon of the moose. Results A total of 789 unique OTUs were used for analysis, which passed the fluorescence and the positive fraction thresholds. There were 73 OTUs, representing 21 bacterial families, which were found exclusively in the rumen samples: Lachnospiraceae, Prevotellaceae and several unclassified families, whereas there were 71 OTUs, representing 22 bacterial families, which were found exclusively in the colon samples: Clostridiaceae, Enterobacteriaceae and several unclassified families. Overall, there were 164 OTUs that were found in 100% of the samples. The Firmicutes were the most dominant bacteria phylum in both the rumen and the colon. Microarray data available at ArrayExpress, accession number E-MEXP-3721. Conclusions Using PhyloTrac and UniFrac computer software, samples clustered into two distinct groups: rumen and colon, confirming that the rumen and colon are distinct environments. There was an apparent correlation of age to cluster, which will be validated by a larger sample size in future studies, but there were no detectable trends based upon gender. PMID:22992344

2012-01-01

335

Phenotypic Signatures Arising from Unbalanced Bacterial Growth  

PubMed Central

Fluctuations in the growth rate of a bacterial culture during unbalanced growth are generally considered undesirable in quantitative studies of bacterial physiology. Under well-controlled experimental conditions, however, these fluctuations are not random but instead reflect the interplay between intra-cellular networks underlying bacterial growth and the growth environment. Therefore, these fluctuations could be considered quantitative phenotypes of the bacteria under a specific growth condition. Here, we present a method to identify “phenotypic signatures” by time-frequency analysis of unbalanced growth curves measured with high temporal resolution. The signatures are then applied to differentiate amongst different bacterial strains or the same strain under different growth conditions, and to identify the essential architecture of the gene network underlying the observed growth dynamics. Our method has implications for both basic understanding of bacterial physiology and for the classification of bacterial strains. PMID:25101949

Tan, Cheemeng; Smith, Robert Phillip; Tsai, Ming-Chi; Schwartz, Russell; You, Lingchong

2014-01-01

336

Bacterial Adhesion at Synthetic Surfaces  

PubMed Central

A systematic investigation into the effect of surface chemistry on bacterial adhesion was carried out. In particular, a number of physicochemical factors important in defining the surface at the molecular level were assessed for their effect on the adhesion of Listeria monocytogenes, Salmonella typhimurium, Staphylococcus aureus, and Escherichia coli. The primary experiments involved the grafting of groups varying in hydrophilicity, hydrophobicity, chain length, and chemical functionality onto glass substrates such that the surfaces were homogeneous and densely packed with functional groups. All of the surfaces were found to be chemically well defined, and their measured surface energies varied from 15 to 41 mJ · m?2. Protein adsorption experiments were performed with 3H-labelled bovine serum albumin and cytochrome c prior to bacterial attachment studies. Hydrophilic uncharged surfaces showed the greatest resistance to protein adsorption; however, our studies also showed that the effectiveness of poly(ethyleneoxide) (PEO) polymers was not simply a result of its hydrophilicity and molecular weight alone. The adsorption of the two proteins approximately correlated with short-term cell adhesion, and bacterial attachment for L. monocytogenes and E. coli also correlated with the chemistry of the underlying substrate. However, for S. aureus and S. typhimurium a different pattern of attachment occurred, suggesting a dissimilar mechanism of cell attachment, although high-molecular-weight PEO was still the least-cell-adsorbing surface. The implications of this for in vivo attachment of cells suggest that hydrophilic passivating groups may be the best method for preventing cell adsorption to synthetic substrates provided they can be grafted uniformly and in sufficient density at the surface. PMID:10543814

Cunliffe, D.; Smart, C. A.; Alexander, C.; Vulfson, E. N.

1999-01-01

337

Continuous monitoring of bacterial attachment  

NASA Technical Reports Server (NTRS)

A major concern with the Space Station Freedom (SSF) water supply system is the control of longterm microbial contamination and biofilm development in the water storage and distribution systems. These biofilms have the potential for harboring pathogens as well as microbial strains containing resistance factors that could negatively influence crew health. The proposed means for disinfecting the water system on SSF (iodine) may encourage the selection of resistant strains. In fact, biofilm bacteria were observed in water lines from the Space Shuttle Columbia (OV-102); therefore, an alternative remediation method is required to disinfect spacecraft water lines. A thorough understanding of colonization events and the physiological parameters that will influence bacteria adhesion is required. The limiting factor for development of this technology is the ability to continuously monitor adhesion events and the effects of biocides on sessile bacteria. Methods were developed to allow bacterial adhesion and subsequent biocidal treatment to be monitored continuously. This technique couples automated image analysis with a continuous flow of a bacterial suspension through an optical flow cell. A strain of Pseudomonas cepacia isolated from the water supply of the Space Shuttle Discovery (OV-103) during STS-39 was grown in a nitrogen-limited continuous culture. This culture was challenged continuously with iodine during growth, and the adhesion characteristics of this strain was measure with regard to flow rate. Various biocides (ozone, hypochlorite, and iodine) were added to the flow stream to evaluate how well each chemical removed the bacteria. After biocide treatment, a fresh bacterial suspension was introduced into the flow cell, and the attachment rate was evaluated on the previously treated surface. This secondary fouling was again treated with biocide to determine the efficacy of multiple batch chemical treatments in removing biofilm.

Koeing, D. W.; Mishra, S. K.; Pierson, D. L.

1994-01-01

338

Familial malignant retroperitoneal paraganglioma.  

PubMed Central

Paragangliomas are neuroendocrine tumours and those occurring in the head and neck have well recognized familial association. Retroperitoneal paragangliomas are uncommon and we present two cases of familial malignant retroperitoneal paraganglioma. Review of the literature revealed marked differences in the incidence and malignant potential of familial and non-familial paraganglioma. In contrast to the cases reported here, familial tumours are generally benign, though they may occur at multiple sites. Familial and non-familial paragangliomas may indeed be different disease entities. Images Figure 1 Figure 2 Figure 3 PMID:2559401

Sebastian, J. P.; Williams, S. E.; Wells, M.; Peake, M. D.

1989-01-01

339

Impacts of different salinities on bacterial biofilm communities in fresh water.  

PubMed

Natural and anthropogenic salinization continuously impacts inland aquatic ecosystems. Associated bacterial biofilms respond rapidly to environmental conditions and are potential bioindicators for changes in water quality. This study evaluates the effects of different salinity concentrations (0.3‰-10‰) on bacterial biofilms communities grown in fresh water from Lake Bosten. Bacterial communities associated with biofilms were analyzed using terminal restriction fragment length polymorphism and clone library analyses of 16S rRNA genes. Results indicated that the attached bacterial community composition (ABCC) changed over several weeks of biofilm growth, but all followed similar bacterial successional trends in the different salinity groups. Detailed analysis showed the following. (i) ABCC did not differ (P > 0.05) in the low-salinity groups (0.3‰-3.5‰), which may be related to the lower osmotic pressure and the shorter time scale (weeks) of their present habitats. (ii) There were significant differences between the oligosaline (3.5‰) and saline (10‰) groups (P < 0.05). In particular, genus Flavobacterium became dominant in attached bacterial communities in the saline groups. The higher abundance of genus Flavobacterium was possibly due to the biological and metabolic characteristics of the bacteria. (iii) Some bacterial taxa can maintain the higher abundance within attached bacteria in the entire process of biofilms growth, such as the genera Hydrogenophaga and Methyloversatilis in Betaproteobacteria and the family Sphingomonadaceae in Alphaproteobacteria. These data suggested that the bacterial successional trends within biofilms seem almost unaffected by salinity (0.3‰-10‰), but ABCC in saline groups (10‰) are notably changed. PMID:24802939

Zhang, Lei; Gao, Guang; Tang, Xiangming; Shao, Keqiang

2014-05-01

340

Genome comparison of bacterial pathogens.  

PubMed

Bacterial pathogens are being sequenced at an increasing rate. To many microbiologists, it appears that there simply is not enough time to digest all the information suddenly available. In this chapter we present several tools for comparison of sequenced pathogenic genomes, and discuss differences between pathogens and non-pathogens. The presented tools allow comparison of large numbers of genomes in a hypothesis-driven manner. Visualization of the results is very important for clear presentation of the results and various ways of graphical representation are introduced. PMID:19696490

Wassenaar, T M; Bohlin, J; Binnewies, T T; Ussery, D W

2009-01-01

341

3D Side View of Bacterial Biofilm  

NSDL National Science Digital Library

Confocal scanning laser microscopy image of a bacterial biofilm composed of Pseudomonas aeruginosa, Pseudomonas fluorescens, and Klebsiella pneumoniae growing on the wall of a polycarbonate flow cell.

American Society For Microbiology

2002-01-01

342

Ibsen's truth, family secrets, and family therapy.  

PubMed

In certain Ibsen plays a character (would-be family therapist) enters during a crisis revolving around family secrets. Taking two such plays as models, this paper examines family processes and clinical issues surrounding secrets and myths. In Ghosts, Ibsen demonstrates the tragic foreclosure visited upon the Alvings' lives by a generation of secrecy. For contrast, in The Wild Duck the would-be reformer Gregers brings out the truth, to expose and correct consequences of his father's past machinations. The biographical roots of Ibsen's obsession with truth and illusion are explored. Lastly, the notion that Ibsen and early family therapist were reformers is viewed in historical perspective. PMID:6628642

Grolnick, L

1983-09-01

343

A Chinese family with phenylketonuria and maternal phenylketonuria detected by family screening.  

PubMed

A 16-year-old boy with classical phenylketonuria (PKU) and mild mental retardation (IQ 69) was detected by the screening of mentally retarded school children in Taiwan with Guthrie's bacterial inhibition assay. The follow-up family study showed that one of his married elder sisters suffered from borderline mental retardation (IQ 75) and was also diagnosed as a classical case of PKU. She had borne one boy and one girl, both suffering from mild mental retardation, microcephaly, delay in linguistic development and severe growth retardation. This is the first known Chinese family with maternal PKU. To prevent future mental retardation caused by maternal PKU, the simultaneous establishment of a register system with a neonatal screening programme, is indicated for the follow-up of PKU girls, screening of the whole family of newly discovered PKU cases, and to exclude unrecognized maternal PKU in women who have given birth to a microcephalic child. PMID:3792388

Hsiao, K J; Chen, C H; Chiu, P C; Huang, S C; Wuu, K D

1986-10-01

344

Organization of the bacterial chromosome.  

PubMed Central

Recent progress in studies on the bacterial chromosome is summarized. Although the greatest amount of information comes from studies on Escherichia coli, reports on studies of many other bacteria are also included. A compilation of the sizes of chromosomal DNAs as determined by pulsed-field electrophoresis is given, as well as a discussion of factors that affect gene dosage, including redundancy of chromosomes on the one hand and inactivation of chromosomes on the other hand. The distinction between a large plasmid and a second chromosome is discussed. Recent information on repeated sequences and chromosomal rearrangements is presented. The growing understanding of limitations on the rearrangements that can be tolerated by bacteria and those that cannot is summarized, and the sensitive region flanking the terminator loci is described. Sources and types of genetic variation in bacteria are listed, from simple single nucleotide mutations to intragenic and intergenic recombinations. A model depicting the dynamics of the evolution and genetic activity of the bacterial chromosome is described which entails acquisition by recombination of clonal segments within the chromosome. The model is consistent with the existence of only a few genetic types of E. coli worldwide. Finally, there is a summary of recent reports on lateral genetic exchange across great taxonomic distances, yet another source of genetic variation and innovation. PMID:2087223

Krawiec, S; Riley, M

1990-01-01

345

Chromophore-enhanced bacterial photothermolysis  

NASA Astrophysics Data System (ADS)

The use of chromophore dyes to enhance the bactericidal effect of laser energy was studied as a means to optimize laser treatment for the decontamination of wound. Using an in vitro study, various concentrations of indocyanine green (ICG), carbon black, and fluorescein were mixed with a suspension of bacteria and plated on tryptic soy agar. Plates were exposed to a laser beam of 10-15 watts for times ranging from 0 to 180 seconds, incubated overnight, and colony counts were performed. Bacteria not mixed with chromophore were used as controls. Six bacterial strains encompassing a range of bacterial types were used: Staphylococcus aureau, Streptococcus pyogenes, Escherichia coli, Pseudomonas aeruginosa, Bacillus cereus spore suspensions, and Clostridium perfringens. Laser treatment alone had no effect on any of the bacteria. Significant killing of gram-positive bacteria, including spores of Bacillus cereus, was observed only with the use of ICG and diode laser energy. No effect was observed using any of the chromophores on the gram-negative bacteria. The results of this study indicate that successful killing of gram-positive bacteria can be achieved using ICG combined with appropriate laser energy and wavelength. Efforts to enhance the susceptibility of gram-negative bacteria to photothermolysis by laser energy were unsuccessful.

Huckleby, Jana K.; Morton, Rebecca J.; Bartels, Kenneth E.

1999-06-01

346

The bacterial translation stress response.  

PubMed

Throughout their life, bacteria need to sense and respond to environmental stress. Thus, such stress responses can require dramatic cellular reprogramming, both at the transcriptional as well as the translational level. This review focuses on the protein factors that interact with the bacterial translational apparatus to respond to and cope with different types of environmental stress. For example, the stringent factor RelA interacts with the ribosome to generate ppGpp under nutrient deprivation, whereas a variety of factors have been identified that bind to the ribosome under unfavorable growth conditions to shut-down (RelE, pY, RMF, HPF and EttA) or re-program (MazF, EF4 and BipA) translation. Additional factors have been identified that rescue ribosomes stalled due to stress-induced mRNA truncation (tmRNA, ArfA, ArfB), translation of unfavorable protein sequences (EF-P), heat shock-induced subunit dissociation (Hsp15), or antibiotic inhibition (TetM, FusB). Understanding the mechanism of how the bacterial cell responds to stress will not only provide fundamental insight into translation regulation, but will also be an important step to identifying new targets for the development of novel antimicrobial agents. PMID:25135187

Starosta, Agata L; Lassak, Jürgen; Jung, Kirsten; Wilson, Daniel N

2014-11-01

347

Bacterial Strain Diversity Within Wounds  

PubMed Central

Significance: Rare bacterial taxa (taxa of low relative frequency) are numerous and ubiquitous in virtually any sample—including wound samples. In addition, even the high-frequency genera and species contain multiple strains. These strains, individually, are each only a small fraction of the total bacterial population. Against the view that wounds contain relatively few kinds of bacteria, this newly recognized diversity implies a relatively high rate of migration into the wound and the potential for diversification during infection. Understanding the biological and medical importance of these numerous taxa is an important new element of wound microbiology. Recent Advances: Only recently have these numerous strains been discovered; the technology to detect, identify, and characterize them is still in its infancy. Multiple strains of both gram-negative and gram-positive bacteria have been found in a single wound. In the few cases studied, the distribution of the bacteria suggests microhabitats and biological interactions. Critical Issues: The distribution of the strains, their phenotypic diversity, and their interactions are still largely uncharacterized. The technologies to investigate this level of genomic detail are still developing and have not been largely deployed to investigate wounds. Future Directions: As advanced metagenomics, single-cell genomics, and advanced microscopy develop, the study of wound microbiology will better address the complex interplay of numerous individually rare strains with both the host and each other. PMID:25566411

Kirkup, Benjamin C.

2015-01-01

348

Analyzing bacterial movements on surfaces.  

PubMed

Bacteria have long been ideal model systems for studying many biological phenomena. But when it comes to motility, we are quite often just figuring out the mechanisms underlying their ability to move in liquid or on surfaces. In the last few decades, research has emphasized the importance for bacteria to be able to adhere to and move on surfaces in order to form complex bacterial communities called biofilms. To better understand the multiple chemical and biophysical mechanisms responsible for the initial interactions of bacteria on surfaces that develop into biofilms, we present here low-cost and easy-to-implement protocols to quantitatively analyze the movement of single bacteria on surfaces by microscopy. These protocols are presented in the case of the human pathogen Neisseria gonorrhoeae that moves on surfaces solely powered by Type IV pili, motility referred to as twitching motility. These methods, however, are applicable for any motile bacteria interacting with surfaces. The precise quantification of motility coupled with genetic tools will enable us to precisely dissect the mechanisms and dynamics of bacterial surface motility which are still poorly understood. PMID:25640444

Munteanu, E Laura; Spielman, Ingrid; Biais, Nicolas

2015-01-01

349

Positional Homology in Bacterial Genomes  

PubMed Central

In comparative genomic studies, syntenic groups of homologous sequence in the same order have been used as supplementary information that can be used in helping to determine the orthology of the compared sequences. The assumption is that ortholo-gous gene copies are more likely to share the same genome positions and share the same gene neighbors. In this study we have defined positional homologs as those that also have homologous neighboring genes and we investigated the usefulness of this distinction for bacterial comparative genomics. We considered the identification of positionaly homologous gene pairs in bacterial genomes using protein and DNA sequence level alignments and found that the positional homologs had on average relatively lower rates of substitution at the DNA level (synonymous substitutions) than duplicate homologs in different genomic locations, regardless of the level of protein sequence divergence (measured with non-synonymous substitution rate). Since gene order conservation can indicate accuracy of orthology assignments, we also considered the effect of imposing certain alignment quality requirements on the sensitivity and specificity of identification of protein pairs by BLAST and FASTA when neighboring information is not available and in comparisons where gene order is not conserved. We found that the addition of a stringency filter based on the second best hits was an efficient way to remove dubious ortholog identifications in BLAST and FASTA analyses. Gene order conservation and DNA sequence homology are useful to consider in comparative genomic studies as they may indicate different orthology assignments than protein sequence homology alone. PMID:19455203

Burgetz, Ingrid J.; Shariff, Salimah; Pang, Andy; Tillier, Elisabeth R. M.

2007-01-01

350

Bacterial community assemblages associated with the phyllosphere, dermosphere, and rhizosphere of tree species of the Atlantic forest are host taxon dependent.  

PubMed

Bacterial communities associated with tree canopies have been shown to be specific to their plant hosts, suggesting that plant species-specific traits may drive the selection of microbial species that comprise their microbiomes. To further examine the degree to which the plant taxa drive the assemblage of bacterial communities in specific plant microenvironments, we evaluated bacterial community structures associated with the phyllosphere, dermosphere, and rhizosphere of seven tree species representing three orders, four families and four genera of plants from a pristine Dense Ombrophilous Atlantic forest in Brazil, using a combination of PCR-DGGE of 16S rRNA genes and clone library sequencing. Results indicated that each plant species selected for distinct bacterial communities in the phyllosphere, dermosphere, and rhizosphere, and that the bacterial community structures are significantly related to the plant taxa, at the species, family, and order levels. Further characterization of the bacterial communities of the phyllosphere and dermosphere of the tree species showed that they were inhabited predominantly by species of Gammaproteobacteria, mostly related to Pseudomonas. In contrast, the rhizosphere bacterial communities showed greater species richness and evenness, and higher frequencies of Alphaproteobacteria and Acidobacteria Gp1. With individual tree species each selecting for their specific microbiomes, these findings greatly increase our estimates of the bacterial species richness in tropical forests and provoke questions concerning the ecological functions of the microbial communities that exist on different plant parts. PMID:24889284

Lambais, Marcio R; Lucheta, Adriano R; Crowley, David E

2014-10-01

351

Intestinal microbiota in metabolic diseases: from bacterial community structure and functions to species of pathophysiological relevance.  

PubMed

The trillions of bacterial cells that colonize the mammalian digestive tract influence both host physiology and the fate of dietary compounds. Gnotobionts and fecal transplantation have been instrumental in revealing the causal role of intestinal bacteria in energy homeostasis and metabolic dysfunctions such as type-2 diabetes. However, the exact contribution of gut bacterial metabolism to host energy balance is still unclear and knowledge about underlying molecular mechanisms is scant. We have previously characterized cecal bacterial community functions and host responses in diet-induced obese mice using omics approaches. Based on these studies, we here discuss issues on the relevance of mouse models, give evidence that the metabolism of cholesterol-derived compounds by gut bacteria is of particular importance in the context of metabolic disorders and that dominant species of the family Coriobacteriaceae are good models to study these functions. PMID:25003516

Clavel, Thomas; Desmarchelier, Charles; Haller, Dirk; Gérard, Philippe; Rohn, Sascha; Lepage, Patricia; Daniel, Hannelore

2014-07-01

352

A Simulation Tool for the Study of Symmetric Inversions in Bacterial Genomes  

NASA Astrophysics Data System (ADS)

We present the tool SIB that simulates genomic inversions in bacterial chromosomes. The tool simulates symmetric inversions but allows the appearance of nonsymmetric inversions by simulating small syntenic blocks frequently observed on bacterial genome comparisons. We evaluate SIB by comparing its results to real genome alignments. We develop measures that allow quantitative comparisons between real pairwise alignments (in terms of dotplots) and simulated ones. These measures allow an evaluation of SIB in terms of dendrograms. We evaluate SIB by comparing its results to whole chromosome alignments and maximum likelihood trees for three bacterial groups (the Pseudomonadaceae family and the Xanthomonas and Shewanella genera). We demonstrate an application of SIB by using it to evaluate the ancestral genome reconstruction tool MGR.

Dias, Ulisses; Dias, Zanoni; Setubal, João C.

353

Effect of heavy metals on bacterial transport  

NASA Astrophysics Data System (ADS)

Adsorption of metals onto bacteria and soil takes place as stormwater runoff infiltrates into the subsurface. Changes in both bacterial surfaces and soil elemental content have been observed, and may alter the attachment of bacteria to soil surfaces. In this study, scanning electron microscopy (SEM) and Energy Dispersive X-ray Spectrometry (EDS) analyses were performed on soil samples equilibrated with synthetic stormwater amended with copper, lead and zinc. The results demonstrate the presence of copper and zinc on soil surfaces. To investigate bacterial attachment behavior, sets of batch sorption experiments were conducted on Escherichia Coli (E. coli) under different chemical conditions by varying solution compositions (nutrient solution vs synthetic stormwater). The adsorption data is best described using theoretical linear isotherms. The equilibrium coefficient (Kd) of E. coli is higher in synthetic stormwater than in nutrient solution without heavy metals. The adsorption of heavy metals onto bacterial surfaces significantly decreases their negative surface charge as determined via zeta potential measurements (-17.0±5.96mv for E. coli equilibrated with synthetic stormwater vs -21.6±5.45mv for E. coli equilibrated with nutrient solution), indicating that bacterial attachment may increase due to the attachment of metals onto bacterial surfaces and their subsequent change in surface charge. The attachment efficiency (?) of bacteria was also calculated and compared for both solution chemistries. Bacterial attachment efficiency (?) in synthetic stormwater is 0.997, which is twice as high as that in nutrient solution(? 0.465). The ratio of bacterial diameter : collector diameter suggests minimal soil straining during bacterial transport. Results suggest that the presence of metals in synthetic stormwater leads to an increase in bacterial attachment to soil surfaces. In terms of designing stormwater infiltration basins, the presence of heavy metals seems to reduce the soil depth required to achieve certain levels of bacterial removal. This study demonstrates the effect of chemical constituents in stormwater runoff on bacterial transport in the subsurface.

Zhang, H.; Olson, M. S.

2010-12-01

354

Family assessment: Centripetal and centrifugal family systems  

Microsoft Academic Search

A consideration of interactional style is useful to both researchers and clinicians interested in family assessment. This paper offers data and process evaluation scales designed to determine family interactional style, conceptualized as a continuum ranging from centripetal (CP) to centrifugal (CF), and containing at the midpoint a mixed area in which facets of both the CP and the CF styles

Martha Kelsey-smith; W. Robert Beavers M. D

1981-01-01

355

The Family Relationships Grid: Measuring Family Structure.  

ERIC Educational Resources Information Center

This study examined the Family Relationships Grid (FRG), a new measure of family structure that evaluates alliances, identification, isolation, and the relative strength of sibling and marital relationships. Subjects were 52 female and 35 male adolescents who were recruited through a university course and who each had at least one sibling.…

Copeland, Anne P.; And Others

356

The potential use of bacterial community succession in forensics as described by high throughput metagenomic sequencing.  

PubMed

Decomposition studies of vertebrate remains primarily focus on data that can be seen with the naked eye, such as arthropod or vertebrate scavenger activity, with little regard for what might be occurring with the microorganism community. Here, we discuss the necrobiome, or community of organisms associated with the decomposition of remains, specifically, the "epinecrotic" bacterial community succession throughout decomposition of vertebrate carrion. Pyrosequencing was used to (1) detect and identify bacterial community abundance patterns that described discrete time points of the decomposition process and (2) identify bacterial taxa important for estimating physiological time, a time-temperature metric that is often commensurate with minimum post-mortem interval estimates, via thermal summation models. There were significant bacterial community structure differences in taxon richness and relative abundance patterns through the decomposition process at both phylum and family taxonomic classification levels. We found a significant negative linear relationship for overall phylum and family taxon richness as decomposition progressed. Additionally, we developed a statistical model using high throughput sequencing data of epinecrotic bacterial communities on vertebrate remains that explained 94.4 % of the time since placement of remains in the field, which was within 2-3 h of death. These bacteria taxa are potentially useful for estimating the minimum post-mortem interval. Lastly, we provide a new framework and standard operating procedure of how this novel approach of using high throughput metagenomic sequencing has remarkable potential as a new forensic tool. Documenting and identifying differences in bacterial communities is key to advancing knowledge of the carrion necrobiome and its applicability in forensic science. PMID:23749255

Pechal, Jennifer L; Crippen, Tawni L; Benbow, M Eric; Tarone, Aaron M; Dowd, Scot; Tomberlin, Jeffery K

2014-01-01

357

Invest in Family*  

PubMed Central

The family is an integral part of one's life. It is very essential that every individual employed or unemployed invests time therein. The family is a source of support and growth for an individual, and the lack of family support or loneliness may be a causative factor in the genesis of psychiatric disorders, especially depression. In India, family plays a paramount role when it comes to mental health of the individual. Tips on how one should invest time in one's family along with the role of a family in one's personal and social structure are discussed.

Shah, Nilesh; De Sousa, Avinash

2015-01-01

358

Evidence of major genes affecting resistance to bacterial cold water disease in rainbow trout using Bayesian methods of segregation analysis  

Technology Transfer Automated Retrieval System (TEKTRAN)

Bacterial cold water disease (BCWD) causes significant economic loss in salmonid aquaculture. We previously detected genetic variation for BCWD resistance in our rainbow trout population, and a family-based selection program to improve resistance was initiated at the National Center for Cool and Col...

359

Evidence of major genes affecting bacterial cold water disease resistance in rainbow trout using Bayesian methods of complex segregation analysis  

Technology Transfer Automated Retrieval System (TEKTRAN)

Bacterial cold water disease (BCWD) causes significant economic loss in salmonid aquaculture. We previously detected genetic variation for BCWD resistance in our rainbow trout population, and a family-based selection program to improve resistance was initiated at the NCCCWA in 2005. The main objec...

360

Biosorption of nickel and cadmium by metal resistant bacterial isolates from agricultural soil irrigated with industrial wastewater  

Microsoft Academic Search

Agricultural soil irrigated with industrial wastewater (more than two decades) analysed for heavy metals revealed high levels of Fe, Cr, Cu, Zn, Ni and Cd. Out of a total of 40 bacterial isolates obtained from these soils, 17 belonged to the family enterobacteriaceae and 10 were Pseudomonas spp. A maximum MIC of 200 for Cd, 400 for Zn and Cu,

Mohd Ikram Ansari; Abdul Malik

2007-01-01

361

Bacterial volatiles promote growth in Arabidopsis  

Microsoft Academic Search

Several chemical changes in soil are associated with plant growth-promoting rhizobacteria (PGPR). Some bacterial strains directly regulate plant physiology by mimicking synthesis of plant hormones, whereas others increase mineral and nitrogen availability in the soil as a way to augment growth. Identification of bacterial chemical messengers that trigger growth promotion has been limited in part by the understanding of how

Choong-Min Ryu; Mohamed A. Farag; Chia-Hui Hu; Munagala S. Reddy; Han-Xun Wei; Paul W. Paré; Joseph W. Kloepper

2003-01-01

362

Bose 4/2004 CHEMICAL TRANSFORMATION (BACTERIAL)  

E-print Network

, but more DNA does not always translate to good transformation efficiency.] 4. Heat shock at 42°C for 45Bose 4/2004 CHEMICAL TRANSFORMATION (BACTERIAL) Overview: This is a standard protocol for bacterial transformation. Materials and equipment: Competent cells Pre-chilled sterile eppendorfs DNA to be transformed

Doering, Tamara

363

Leading Edge Bacterial Genomics and Pathogen Evolution  

E-print Network

Leading Edge Review Bacterial Genomics and Pathogen Evolution David M. Raskin,1 Rekha Seshadri,2 Medical School, Boston, MA 02115, USA 2 The Institute for Genomic Research, 9712 Medical Center Drive.02.002 The availability of hundreds of bacterial genome sequences has altered the study of bacte- rial pathogenesis

Mekalanos, John

364

Use of Bacteriophages to control bacterial pathogens  

Technology Transfer Automated Retrieval System (TEKTRAN)

Lytic bacteriophages can provide a natural method and an effective alternative to antibiotics to reduce bacterial pathogens in animals, foods, and other environments. Bacteriophages (phages) are viruses which infect bacterial cells and eventually kill them through lysis, and represent the most abun...

365

Bacterial Monitoring for the Buck Creek Watershed  

E-print Network

The “Bacterial Monitoring for the Buck Creek Watershed” project was developed in response to the creek’s listing on the Texas Water Quality Inventory and 303(d) List due to a bacterial impairment and subsequent total maximum daily load (TMDL...

366

Recent advances in bacterial heme protein biochemistry  

PubMed Central

Recent progress in genetics, fed by the burst in genome sequence data, has led to the identification of a host of novel bacterial heme proteins that are now being characterized in structural and mechanistic terms. The following short review highlights very recent work with bacterial heme proteins involved in the uptake, biosynthesis, degradation, and use of heme in respiration and sensing. PMID:21339081

Mayfield, Jeffery A.; Dehner, Carolyn A.; DuBois, Jennifer L.

2011-01-01

367

Bacterial Colonization of Particles: Growth and Interactions  

Microsoft Academic Search

Marine particles in the ocean are exposed to diverse bacterial communities, and colonization and growth of attached bacteria are important processes in the degradation and transformation of the particles. In an earlier study, we showed that the initial colonization of model particles by individual bacterial strains isolated from marine aggregates was a function of attachment and detachment. In the present

Hans-Peter Grossart; T. Kiorboe; Kam Tang; Helle Ploug

2003-01-01

368

Bacterial Cellulose Production from Beet Molasses  

Microsoft Academic Search

Bacterial friendly cellulose is produced from beet molasses using Gluconacetobacter xylinus ATCC 10245. The yield of the bacterial cellulose (BC) produced from beet molasses was higher than that using glucose as a sole carbon source. The structure of BC produced in presence of beet molasses was studied using IR spectroscopy and X-ray diffractometry. IR spectra show the relative absorbance of

Sherif M. A. S. Keshk; Taha M. A. Razek; Kazuhiko Sameshima

2006-01-01

369

Bacterial Colonization In Suspected Sexually Abused Children  

Microsoft Academic Search

ObjectivePrevious studies concluded that symptomatic prepubertal children with Gardnerella vaginalis infection should be investigated for child sexual abuse. Gardnerella vaginalis is only one out of a group of organism that cause bacterial vaginosis. The aim of the study was to report the frequency of bacterial colonization as well as sexually transmitted diseases and to correlate these data with patient characteristics.

Petra Kohlberger; Dagmar Bancher-Todesca

2007-01-01

370

Asymptomatic bacterial vaginosis: Response to therapy  

Microsoft Academic Search

Objective: Bacterial vaginosis causes symptomatic vaginal discharge and has been associated with preterm birth and with the acquisition of human immunodeficiency virus. Half of all women with bacterial vaginosis are free of symptoms, and treatment of these women is controversial. The objective of this study was to determine the extent of poor symptom recognition in this group of women. Study

Jane R. Schwebke

2000-01-01

371

Bacterial strategies to overcome insect defences  

Microsoft Academic Search

Recent genetic and molecular analyses have revealed how several strategies enable bacteria to persist and overcome insect immune defences. Genetic and genomic tools that can be used with Drosophila melanogaster have enabled the characterization of the pathways that are used by insects to detect bacterial invaders and combat infection. Conservation of bacterial virulence factors and insect immune repertoires indicates that

Isabelle Vallet-Gely; Bruno Lemaitre; Frédéric Boccard

2008-01-01

372

Sharing of quorum-sensing signals and role of interspecies communities in a bacterial plant disease  

PubMed Central

Pathogenic bacteria interact not only with the host organism but most probably also with the resident microbial flora. In the knot disease of the olive tree (Olea europaea), the causative agent is the bacterium Pseudomonas savastanoi pv. savastanoi (Psv). Two bacterial species, namely Pantoea agglomerans and Erwinia toletana, which are not pathogenic and are olive plant epiphytes and endophytes, have been found very often to be associated with the olive knot. We identified the chemical signals that are produced by strains of the three species isolated from olive knot and found that they belong to the N-acyl-homoserine lactone family of QS signals. The luxI/R family genes responsible for the production and response to these signals in all three bacterial species have been identified and characterized. Genomic knockout mutagenesis and in planta experiments showed that virulence of Psv critically depends on QS; however, the lack of signal production can be complemented by wild-type E. toletana or P. agglomerans. It is also apparent that the disease caused by Psv is aggravated by the presence of the two other bacterial species. In this paper we discuss the potential role of QS in establishing a stable consortia leading to a poly-bacterial disease. PMID:21677694

Hosni, Taha; Moretti, Chiaraluce; Devescovi, Giulia; Suarez-Moreno, Zulma Rocio; Fatmi, M' Barek; Guarnaccia, Corrado; Pongor, Sandor; Onofri, Andrea; Buonaurio, Roberto; Venturi, Vittorio

2011-01-01

373

Composition, uniqueness and variability of the epiphytic bacterial community of the green alga Ulva australis  

PubMed Central

Green Ulvacean marine macroalgae are distributed worldwide in coastal tidal and subtidal ecosystems. As for many living surfaces in the marine environment, little is known concerning the epiphytic bacterial biofilm communities that inhabit algal surfaces. This study reports on the largest published libraries of near full-length 16S rRNA genes from a marine algal surface (5293 sequences from six samples) allowing for an in-depth assessment of the diversity and phylogenetic profile of the bacterial community on a green Ulvacean alga. Large 16S rRNA gene libraries of surrounding seawater were also used to determine the uniqueness of this bacterial community. The surface of Ulva australis is dominated by sequences of Alphaproteobacteria and the Bacteroidetes, especially within the Rhodobacteriaceae, Sphingomonadaceae, Flavobacteriaceae and Sapropiraceae families. Seawater libraries were also dominated by Alphaproteobacteria and Bacteroidetes sequences, but were shown to be clearly distinct from U. australis libraries through the clustering of sequences into operational taxonomic units and Bray–Curtis similarity analysis. Almost no similarity was observed between these two environments at the species level, and only minor similarity was observed at levels of sequence clustering representing clades of bacteria within family and genus taxonomic groups. Variability between libraries of U. australis was relatively high, and a consistent sub-population of bacterial species was not detected. The competitive lottery model, originally derived to explain diversity in coral reef fishes, may explain the pattern of colonization of this algal surface. PMID:21048801

Burke, Catherine; Thomas, Torsten; Lewis, Matt; Steinberg, Peter; Kjelleberg, Staffan

2011-01-01

374

Bacterial detection: from microscope to smartphone.  

PubMed

The ubiquitous nature of bacteria enables them to survive in a wide variety of environments. Hence, the rise of various pathogenic species that are harmful to human health raises the need for the development of accurate sensing systems. Sensing systems are necessary for diagnosis and epidemiological control of pathogenic organism, especially in the food-borne pathogen and sanitary water treatment facility' bacterial populations. Bacterial sensing for the purpose of diagnosis can function in three ways: bacterial morphological visualization, specific detection of bacterial component and whole cell detection. This paper provides an overview of the currently available bacterial detection systems that ranges from microscopic observation to state-of-the-art smartphone-based detection. PMID:24836016

Gopinath, Subash C B; Tang, Thean-Hock; Chen, Yeng; Citartan, Marimuthu; Lakshmipriya, Thangavel

2014-10-15

375

21 CFR 868.5260 - Breathing circuit bacterial filter.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Breathing circuit bacterial filter. 868.5260...Therapeutic Devices § 868.5260 Breathing circuit bacterial filter. (a) Identification. A breathing circuit bacterial filter is a...

2010-04-01

376

21 CFR 868.5260 - Breathing circuit bacterial filter.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Breathing circuit bacterial filter. 868.5260...Therapeutic Devices § 868.5260 Breathing circuit bacterial filter. (a) Identification. A breathing circuit bacterial filter is a...

2011-04-01

377

21 CFR 868.5260 - Breathing circuit bacterial filter.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Breathing circuit bacterial filter. 868.5260...Therapeutic Devices § 868.5260 Breathing circuit bacterial filter. (a) Identification. A breathing circuit bacterial filter is a...

2013-04-01

378

21 CFR 868.5260 - Breathing circuit bacterial filter.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Breathing circuit bacterial filter. 868.5260...Therapeutic Devices § 868.5260 Breathing circuit bacterial filter. (a) Identification. A breathing circuit bacterial filter is a...

2012-04-01

379

21 CFR 868.5260 - Breathing circuit bacterial filter.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Breathing circuit bacterial filter. 868.5260...Therapeutic Devices § 868.5260 Breathing circuit bacterial filter. (a) Identification. A breathing circuit bacterial filter is a...

2014-04-01

380

Bacterial interactions in dental biofilm  

PubMed Central

Biofilms are masses of microorganisms that bind to and multiply on a solid surface, typically with a fluid bathing the microbes. The microorganisms that are not attached but are free-floating in an aqueous environment are termed planktonic cells. Traditionally, microbiology research has addressed results from planktonic bacterial cells. However, many recent studies have indicated that biofilms are the preferred form of growth of most microbes and particularly those of a pathogenic nature. Biofilms on animal hosts have significantly increased resistance to various antimicrobials compared to planktonic cells. These microbial communities form microcolonies that interact with each other using very sophisticated communication methods (i.e., quorum-sensing). The development of unique microbiological tools to detect and assess the various biofilms around us is a tremendously important focus of research in many laboratories. In the present review, we discuss the major biofilm mechanisms and the interactions among oral bacteria. PMID:21778817

Huang, Ruijie; Li, Mingyun

2011-01-01

381

Fluid Dynamics of Bacterial Turbulence  

NASA Astrophysics Data System (ADS)

Self-sustained turbulent structures have been observed in a wide range of living fluids, yet no quantitative theory exists to explain their properties. We report experiments on active turbulence in highly concentrated 3D suspensions of Bacillus subtilis and compare them with a minimal fourth-order vector-field theory for incompressible bacterial dynamics. Velocimetry of bacteria and surrounding fluid, determined by imaging cells and tracking colloidal tracers, yields consistent results for velocity statistics and correlations over 2 orders of magnitude in kinetic energy, revealing a decrease of fluid memory with increasing swimming activity and linear scaling between kinetic energy and enstrophy. The best-fit model allows for quantitative agreement with experimental data.

Dunkel, Jörn; Heidenreich, Sebastian; Drescher, Knut; Wensink, Henricus H.; Bär, Markus; Goldstein, Raymond E.

2013-05-01

382

Bacterial nutrients in drinking water.  

PubMed Central

Regrowth of coliform bacteria in distribution systems has been a problem for a number of water utilities. Efforts to solve the regrowth problem have not been totally successful. The current project, which was conducted at the New Jersey American Water Co.-Swimming River Treatment Plant, showed that the occurrence of coliform bacteria in the distribution system could be associated with rainfall, water temperatures greater than 15 degrees C, total organic carbon levels greater than 2.4 mg/liter, and assimilable organic carbon levels greater than 50 micrograms of acetate carbon equivalents per liter. A multiple linear regression model based on free chlorine residuals present in dead-end sections of the distribution system and temperature predicted 83.8% of the heterotrophic plate count bacterial variation. To limit the growth of coliform bacteria in drinking water, the study concludes that assimilable organic carbon levels should be reduced to less than 50 micrograms/liter. PMID:2039235

LeChevallier, M W; Schulz, W; Lee, R G

1991-01-01

383

Bacterial oncogenesis in the colon  

PubMed Central

The human colon plays host to a diverse and metabolically complex community of microorganisms. While the colonic microbiome has been suggested to contribute to the development of colorectal cancer (CRC), a definitive link has not been made. The role in which the colon microflora could contribute to the initiation and/or progression of CRC is explored in this review. Potential mechanisms of bacterial oncogenesis are presented, along with lines of evidence derived from animal models of microbially induced CRC. Particular focus is given to the oncogenic capabilities of enterotoxigenic Bacteroides fragilis. Recent progress in defining the microbiome of CRC in the human population is evaluated, and the future challenges of linking specific etiologic agents to CRC are emphasized. PMID:23534358

Dejea, Christine; Wick, Elizabeth; Sears, Cynthia L

2013-01-01

384

Bacterial Actins? An Evolutionary Perspective  

NASA Technical Reports Server (NTRS)

According to the conventional wisdom, the existence of a cytoskeleton in eukaryotes and its absence in prokaryotes constitute a fundamental divide between the two domains of life. An integral part of the dogma is that a cytoskeleton enabled an early eukaryote to feed upon prokaryotes, a consequence of which was the occasional endosymbiosis and the eventual evolution of organelles. Two recent papers present compelling evidence that actin, one of the principal components of a cytoskeleton, has a homolog in Bacteria that behaves in many ways like eukaryotic actin. Sequence comparisons reveml that eukaryotic actin and the bacterial homolog (mreB protein), unlike many other proteins common to eukaryotes and Bacteria, have very different and more highly extended evolutionary histories.

Doolittle, Russell F.; York, Amanda L.

2003-01-01

385

Bacterial sorption of heavy metals.  

PubMed Central

Four bacteria, Bacillus cereus, B. subtilis, Escherichia coli, and Pseudomonas aeruginosa, were examined for the ability to remove Ag+, Cd2+, Cu2+, and La3+ from solution by batch equilibration methods. Cd and Cu sorption over the concentration range 0.001 to 1 mM was described by Freundlich isotherms. At 1 mM concentrations of both Cd2+ and Cu2+, P. aeruginosa and B. cereus were the most and least efficient at metal removal, respectively. Freundlich K constants indicated that E. coli was most efficient at Cd2+ removal and B. subtilis removed the most Cu2+. Removal of Ag+ from solution by bacteria was very efficient; an average of 89% of the total Ag+ was removed from the 1 mM solution, while only 12, 29, and 27% of the total Cd2+, Cu2+, and La3+, respectively, were sorbed from 1 mM solutions. Electron microscopy indicated that La3+ accumulated at the cell surface as needlelike, crystalline precipitates. Silver precipitated as discrete colloidal aggregates at the cell surface and occasionally in the cytoplasm. Neither Cd2+ nor Cu2+ provided enough electron scattering to identify the location of sorption. The affinity series for bacterial removal of these metals decreased in the order Ag greater than La greater than Cu greater than Cd. The results indicate that bacterial cells are capable of binding large quantities of different metals. Adsorption equations may be useful for describing bacterium-metal interactions with metals such as Cd and Cu; however, this approach may not be adequate when precipitation of metals occurs. Images PMID:2515800

Mullen, M D; Wolf, D C; Ferris, F G; Beveridge, T J; Flemming, C A; Bailey, G W

1989-01-01

386

Oral bacterial DNA findings in pericardial fluid  

PubMed Central

Background We recently reported that large amounts of oral bacterial DNA can be found in thrombus aspirates of myocardial infarction patients. Some case reports describe bacterial findings in pericardial fluid, mostly done with conventional culturing and a few with PCR; in purulent pericarditis, nevertheless, bacterial PCR has not been used as a diagnostic method before. Objective To find out whether bacterial DNA can be measured in the pericardial fluid and if it correlates with pathologic–anatomic findings linked to cardiovascular diseases. Methods Twenty-two pericardial aspirates were collected aseptically prior to forensic autopsy at Tampere University Hospital during 2009–2010. Of the autopsies, 10 (45.5%) were free of coronary artery disease (CAD), 7 (31.8%) had mild and 5 (22.7%) had severe CAD. Bacterial DNA amounts were determined using real-time quantitative PCR with specific primers and probes for all bacterial strains associated with endodontic disease (Streptococcus mitis group, Streptococcus anginosus group, Staphylococcus aureus/Staphylococcus epidermidis, Prevotella intermedia, Parvimonas micra) and periodontal disease (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola, Fusobacterium nucleatus, and Dialister pneumosintes). Results Of 22 cases, 14 (63.6%) were positive for endodontic and 8 (36.4%) for periodontal-disease-associated bacteria. Only one case was positive for bacterial culturing. There was a statistically significant association between the relative amount of bacterial DNA in the pericardial fluid and the severity of CAD (p=0.035). Conclusions Oral bacterial DNA was detectable in pericardial fluid and an association between the severity of CAD and the total amount of bacterial DNA in pericardial fluid was found, suggesting that this kind of measurement might be useful for clinical purposes. PMID:25412607

Louhelainen, Anne-Mari; Aho, Joonas; Tuomisto, Sari; Aittoniemi, Janne; Vuento, Risto; Karhunen, Pekka J.; Pessi, Tanja

2014-01-01

387

Isolation and Characterization of a Fucoidan-Degrading Marine Bacterial Strain and Its Fucoidanase  

Microsoft Academic Search

A marine bacterial strain that degraded fucoidan from Kjellmaniella crassifolia (class Phaeophyceae, order Laminariales, family Laminariaceae) was isolated in our laboratory. The strain was gram-negative, ubiquinone 8 was the predominant respiratory quinone, and the GC-content of its genomic DNA was 36%. The cells of the strain were rod-shaped (2.0 ?m long × 1.0 ?m wide), and each cell was motile by means

Takeshi Sakai; Takashi Kawai; Ikunoshin Kato

2004-01-01

388

Efficient haplotyping for families  

E-print Network

Hapi is a novel dynamic programming algorithm for haplotyping nuclear families that outperforms contemporary family-based haplotyping algorithms. Haplotypes are useful for mapping and identifying genes which cause and ...

Williams, Amy Lynne, Ph.D. Massachusetts Institute of Technology

2010-01-01

389

EATING DISORDERS FAMILY PROBLEMS  

E-print Network

ANXIETY DEPRESSION EATING DISORDERS FAMILY PROBLEMS GENERAL CONCERNS INTERPERSONAL DIFFICULTIES.946.5117 Counselling and Cyber Counselling Services to Help With: · Anxiety · Depression · Eating disorders · Family

Toronto, University of

390

Improving Family Communications  

MedlinePLUS

... Pediatric First Aid for Caregivers and Teachers (PedFACTs) Teaching Package Infant CPR Anytime® (English/Spanish) Nutrition: What Every Parent Needs to Know Family Life Health Management - Medical Home Family Dynamics Adoption & Foster Care Communication & Discipline Types ...

391

Helping Friends and Family  

MedlinePLUS

... chapter Join our online community Helping Friends and Family Part of living well with Alzheimerâ??s is adjusting to your â??new normalâ? and helping family and friends do the same. Knowing what to ...

392

Family Policy in Scotland   

E-print Network

This briefing looks at the development of family policy in Scotland, considers the interplay between devolved and reserved matters, outlines the Departments of the Scottish Executive responsible for family policy, and considers the relationship...

Wasoff, Fran; Hill, Malcolm

393

Familial Periodic Paralyses  

MedlinePLUS

NINDS Familial Periodic Paralyses Information Page Synonym(s): Periodic Paralyses Table of Contents (click to jump to sections) What are Familial Periodic Paralyses? Is there any treatment? What is the prognosis? What research is ...

394

Fatherhood and Family Support.  

ERIC Educational Resources Information Center

On the assumption that fathers have been relatively absent from family support programs, this publication of the Family Resource Coalition addresses the role of fathers in family support programs, examines the impact of fathers on their children, and describes programs involving fathers successfully. Articles include: (1) "What's Behind the…

Goetz, Kathy, Ed.

1996-01-01

395

Year of the Family.  

ERIC Educational Resources Information Center

This special issue focuses on problems and challenges confronting the California family and on research and extension efforts to provide at least partial answers. Research briefs by staff include "Challenges Confront the California Family" (state trends in poverty, divorce, single-parent families, child abuse, delinquency, teen births, limited…

California Agriculture, 1994

1994-01-01

396

The Family Leukemia Association  

ERIC Educational Resources Information Center

An association of families of children with leukemia, the Family Leukemia Association (FLA), was recently established in Toronto. This paper discusses (a) philosophy of the FLA; (b) formative years of this organization; (c) problems encountered by leukemic children and their families; and (d) the FLA's past and future educational and social…

Pollitt, Eleanor

1976-01-01

397

Families for All Children.  

ERIC Educational Resources Information Center

This bulletin reflects the commitment of Syracuse University's Center on Human Policy to the idea that children belong with families. The bulletin contains a policy statement which recommends; that all children, regardless of disability, belong with families and need enduring relationships with adults; that families with severely disabled children…

Shoultz, Bonnie, Ed.; Kalyanpur, Maya, Ed.

398

Doing Better for Families  

ERIC Educational Resources Information Center

All OECD governments want to give parents more choice in their work and family decisions. This book looks at the different ways in which governments support families. It seeks to provide answers to questions like: Is spending on family benefits going up, and how does it vary by the age of the child? Has the crisis affected public support for…

OECD Publishing (NJ3), 2011

2011-01-01

399

Establishing Family Math.  

ERIC Educational Resources Information Center

The Family Math Program is an outgrowth of the Equals Program at the Lawrence Hall of Science at UC Berkeley. Piloted in 1982 in Richmond, California, this widespread program boasts a simple philosophy: Families "doing math" will get the same result as families who read--improved skills and enjoyment. The program also confronts parental math…

Bobango, Janet, Milgram, Joel

1993-01-01

400

The Family Farm Project  

NSDL National Science Digital Library

Kenyon College's Family Farm Project, "a three-year study exploring family farming and community life in Knox County, Ohio," presents an intimate multimedia view of the daily life of the family farm, which some consider a vanishing institution in America.

1996-01-01

401

Treatment of violent families.  

PubMed Central

Family violence is responsible for a significant proportion of homicides, a major cause of premature deaths in African-Americans. This article reviews the prevalence of family violence and explores associated risk factors. Principles and tips of treatment, along with a cognitive framework to guide the actual therapy, are outlined. Finally, issues of preventing family violence are discussed. PMID:2038079

Bell, C. C.; Chance-Hill, G.

1991-01-01

402

FAMILY MEDICINE* Definition Of  

E-print Network

healthcare in family medicine is the achievement of optimal physical and mental health through accessible the patient's total health needs, and provides personal care within one or more fields of medicine. The family in the context of the family and the community. This care emphasizes disease prevention and health promotion

Finley Jr., Russell L.

403

Family Life Cycle Stages  

Microsoft Academic Search

Individual life stages happen within the context of family life. This article describes Betty Carter's and Monica McGoldrick's Family Life Cycle stages as a context for Eric Erikson's stages of psychosocial development, Daniel Levinson's Stages of a Man's Life, and Jean Piaget's stages of cognitive development. The author juxtaposes the tasks of each family life stage with the individual life

M. A. Armour

1995-01-01

404

Religion and the Family.  

ERIC Educational Resources Information Center

Examines religion's place in the social sciences, reciprocal influences of family and religion, cohesion/polarization in American Catholic families, religion in Middletown, USA, gender and religion in Canadian and American students, domestic/religious individualism and suicide, and the New Christian Right's view of the family. (BH)

Thomas, Darwin L., Ed.

1985-01-01

405

Family Member Casualty Assistance  

E-print Network

Family Member Casualty Assistance Handbook Taking Care of Our Own #12;2 TABLE OF CONTENTS 1: Important Documents and Information p 22 Appendix 2: Developing Family Plans in Case Your.S. Army Corps of Engineer (USACE*) Family Members whose Soldier or Department of the Army (DA) Civilian

US Army Corps of Engineers

406

Family Housing Wysocki House  

E-print Network

Family Housing Wysocki House 911 North Pleasant Street University of Massachusetts Amherst, MA):________________________________________ STUDENT ENROLLMENT: Undergrad Graduate Are you a current Family Housing Tenant?_________ UMASS STAFF WOULD LIKE US TO KNOW? LIST REMARKS BELOW: SEE REVERSE SIDE FOR APARTMENT PREFERENCE SELECTION FAMILY

Massachusetts at Amherst, University of

407

Family Member Casualty Assistance  

E-print Network

Family Member Casualty Assistance Handbook Taking Care of Our Own #12;2 TABLE OF CONTENTS 1: Important Documents and Information p 18 Appendix 2: Developing a Family Plan in Case Your.S. Army Corps of Engineer (USACE*) Family Members whose Soldier or Department of the Army (DA) Civilian

US Army Corps of Engineers

408

Family Employability Development Plan.  

ERIC Educational Resources Information Center

In the Family Employability Development Plan (FEDP) process, a facilitator works with the family to help its members acquire the skills to develop their own plan for economic independence. The facilitator helps coordinate the interagency effort and helps the family become empowered to carry out its own plan. Carried out as a pilot project in 13…

Michigan State Dept. of Education, Lansing. Adult Extended Learning Services.

409

Employment Characteristics of Families  

NSDL National Science Digital Library

The Bureau of Labor Statistics site offers data on the employment characteristics of American families. The statistics include data on employment and unemployment in families by race, relationship, sex, marital status, presence of children in the family, and presence of children under three, among others. The data can be accessed from a table of contents or reviewed in an extensive news release.

410

Strengthening America's Families.  

ERIC Educational Resources Information Center

Improving parenting practices and the family environment is the most effective, enduring strategy for combating juvenile delinquency. Describes the Office of Juvenile Justice and Delinquency Prevention's Strengthening America's Families Initiative. Highlights several family-focused prevention programs identified as exemplary, explaining how they…

Alvarado, Rose; Kumpfer, Karol

2000-01-01

411

Socialization and Family Violence.  

ERIC Educational Resources Information Center

Community professionals are dealing increasingly with family conflict and violence but typically have little training in this area. Family dynamics in the causation and consequences of intra-family aggression were studied in a project involving seven groups of community professionals, including lawyers, ministers, physicians, police, nurses,…

Hutchison, Ira W.

412

Family Customs and Traditions.  

ERIC Educational Resources Information Center

Recognizing the importance of maintaining open communication with immediate and extended family members, this book provides a compilation of ideas for family traditions and customs that are grounded in compassion and human kindness. The traditions were gathered from families in the United States and Canada who responded to advertisements in…

MacGregor, Cynthia

413

Familial hyperuricemic nephropathy  

Microsoft Academic Search

This report describes a Polynesian family that had the rare combination of hyperuricemia, precocious gout, hypertension, and renal failure at an early age, with an autosomal dominant inheritance. One family member had renal biopsy evidence of interstitial urate crystal deposition, a surprisingly uncommon observation in such families, and most had decreased fractional excretion of urate, reflecting either decreased secretion or

Reiter Loretta; A. Mark Brown

1995-01-01

414

Families and Assisted Living  

ERIC Educational Resources Information Center

Purpose: Despite growing research on assisted living (AL) as a residential care option for older adults, the social ramifications of residents' transitions to AL are relatively unexplored. This article examines family involvement in AL, including family structures of residents, types of involvement from family members living outside the AL…

Gaugler, Joseph E.; Kane, Robert L.

2007-01-01

415

Selective detection of bacterial layers with terahertz plasmonic antennas  

PubMed Central

Current detection and identification of micro-organisms is based on either rather unspecific rapid microscopy or on more accurate but complex and time-consuming procedures. In a medical context, the determination of the bacteria Gram type is of significant interest. The diagnostic of microbial infection often requires the identification of the microbiological agent responsible for the infection, or at least the identification of its family (Gram type), in a matter of minutes. In this work, we propose to use terahertz frequency range antennas for the enhanced selective detection of bacteria types. Several microorganisms are investigated by terahertz time-domain spectroscopy: a fast, contactless and damage-free investigation method to gain information on the presence and the nature of the microorganisms. We demonstrate that plasmonic antennas enhance the detection sensitivity for bacterial layers and allow the selective recognition of the Gram type of the bacteria. PMID:23162730

Berrier, Audrey; Schaafsma, Martijn C.; Nonglaton, Guillaume; Bergquist, Jonas; Rivas, Jaime Gómez

2012-01-01

416

Bacterial Carbonic Anhydrases as Drug Targets: Toward Novel Antibiotics?  

PubMed Central

Carbonic anhydrases (CAs, EC 4.2.1.1) are metalloenzymes which catalyze the hydration of carbon dioxide to bicarbonate and protons. Many pathogenic bacteria encode such enzymes belonging to the ?-, ?-, and/or ?-CA families. In the last decade, the ?-CAs from Neisseria spp. and Helicobacter pylori as well as the ?-class enzymes from Escherichia coli, H. pylori, Mycobacterium tuberculosis, Brucella spp., Streptococcus pneumoniae, Salmonella enterica, and Haemophilus influenzae have been cloned and characterized in detail. For some of these enzymes the X-ray crystal structures were determined, and in vitro and in vivo inhibition studies with various classes of inhibitors, such as anions, sulfonamides and sulfamates reported. Although efficient inhibitors have been reported for many such enzymes, only for Neisseria spp., H. pylori, B. suis, and S. pneumoniae enzymes it has been possible to evidence inhibition of bacterial growth in vivo. Thus, bacterial CAs represent promising targets for obtaining antibacterials devoid of the resistance problems of the clinically used such agents but further studies are needed to validate these and other less investigated enzymes as novel drug targets. PMID:21779249

Supuran, Claudiu T.

2011-01-01

417

Family Emergency Preparedness Plan 1 Family Emergency Preparedness Plan  

E-print Network

#12;#12;Family Emergency Preparedness Plan 1 Family Emergency Preparedness Plan Why Plan Emergency Telephone Numbers.....................................................26 Credits The Family Military Department, Emergency Management Division. #12;2 Family Emergency Preparedness Plan Why plan

Noble, James S.

418

Postinfluenza Bacterial Pneumonia: Host Defenses Gone Awry  

PubMed Central

Influenza is a common respiratory pathogen causing both seasonal and pandemic disease. Influenza infection predisposes the host to secondary bacterial infection of the respiratory tract, which is a major cause of both morbidity and mortality in flu-related disease. In this review, we will discuss innate and adaptive antiviral responses during influenza infection, and review how these responses modulate protective immunity against secondary bacterial pathogens of the lung. Specific emphasis will be placed on implications of bacterial superinfection and mechanisms involved. PMID:20726789

Ballinger, Megan N.

2010-01-01

419

MICROBIOLOGY: A Bacterial Pathogen Sees the Light  

NSDL National Science Digital Library

Access to the article is free, however registration and sign-in are required. Photosensitive proteins abound in the bacterial kingdom, but their cellular functions often remain a mystery. In this Perspective Kennis and Crosson discuss how Swartz et al. identified a functional role for a new type of light sensor in bacteria--light, oxygen, or voltage (LOV) histidine kinase. In the notorious pathogen Brucella abortus, light increases the enzymatic activity of this kinase, which, remarkably, increases virulence of the bacterium. Related LOV histidine kinases are conserved across a range of bacterial taxa, suggesting that this virulence pathway could be one of many new photosensory pathways regulating bacterial physiology.

John T. M. Kennis (Faculty of Sciences, Vrije Universiteit; Biophysics Department)

2007-08-24

420

Nanoantennas as biomarkers for bacterial detection.  

PubMed

Understanding the biology of bacteria is critical for exploiting their beneficial properties and for preventing and treating bacterial diseases. Nanobioscience is an area that has recently seen major scientific progress. Here, we demonstrate that a raspberry-shaped nanostructure with a high density of gold nanoparticles acts like an excellent antenna due to its optical properties, which permit sensitive detection and analysis of bacterial cells. By using antibodies, these nanoantennas can be engineered to recognize only specific bacterial species. This system provides a new technique that will allow for more sensitive detection of specific bacteria. PMID:25782716

Shiigi, Hiroshi; Kinoshita, Takamasa; Fukuda, Maho; Le, Dung Quynh; Nishino, Tomoaki; Nagaoka, Tsutomu

2015-04-01

421

Family Ties: Communicating Identity Through Jointly Told Family Stories  

Microsoft Academic Search

Family stories work to construct family identity. Little research, however, has examined storytelling in families. This study examined storytelling content and process to assess the extent to which families jointly integrated or fragmented a shared sense of identity and how these discursive practices relate to family qualities. Results of a study involving 58 family triads indicate relationships between story theme

Jody Koenig Kellas

2005-01-01

422

[Host responses to bacterial infections].  

PubMed

Pathogenic bacteria and host defense system have been evolved by their offense and defense. In vivo research is crucial for elucidation of interactions between them. I have investigated their offence and defense by various standpoints using mouse models of Listeria monocytogenes and Staphylococcus aureus infections. Herein, the results of my research including the roles of endogenous cytokines in host defense, the attenuation of host defense mechanism in obesity and diabetes, the development of vaccines against S. aureus infection by staphylococcal enterotoxin (SE) family molecules, and the emesis-inducing mechanism of SEA are described. PMID:25186639

Nakane, Akio

2014-01-01

423

Molecular biology of bacterial bioluminescence.  

PubMed Central

The cloning and expression of the lux genes from different luminescent bacteria including marine and terrestrial species have led to significant advances in our knowledge of the molecular biology of bacterial bioluminescence. All lux operons have a common gene organization of luxCDAB(F)E, with luxAB coding for luciferase and luxCDE coding for the fatty acid reductase complex responsible for synthesizing fatty aldehydes for the luminescence reaction, whereas significant differences exist in their sequences and properties as well as in the presence of other lux genes (I, R, F, G, and H). Recognition of the regulatory genes as well as diffusible metabolites that control the growth-dependent induction of luminescence (autoinducers) in some species has advanced our understanding of this unique regulatory mechanism in which the autoinducers appear to serve as sensors of the chemical or nutritional environment. The lux genes have now been transferred into a variety of different organisms to generate new luminescent species. Naturally dark bacteria containing the luxCDABE and luxAB genes, respectively, are luminescent or emit light on addition of aldehyde. Fusion of the luxAB genes has also allowed the expression of luciferase under a single promoter in eukaryotic systems. The ability to express the lux genes in a variety of prokaryotic and eukaryotic organisms and the ease and sensitivity of the luminescence assay demonstrate the considerable potential of the widespread application of the lux genes as reporters of gene expression and metabolic function. Images PMID:2030669

Meighen, E A

1991-01-01

424

Radionuclide scintigraphy of bacterial nephritis  

SciTech Connect

Pyelonephritis is a leading cause of renal failure and is expected to cost as much as three billion dollars in 1984. The diagnosis of urinary tract infection is usually not difficult. However, localization of the infection within the renal parenchyma as opposed to the collecting system is much more difficult. Flank pain, fever, bacteiuria and evidence of parenchymal involvement by intravenous urography may be absent or unrecognized particularly in the infant. Ultrasound and Nuclear Medicine are advocated as better methods to define parenchymal involvement. Such definition is important in the consideration of treatment since parenchymal involvement of the kidney carries a much more ominous potential outcome than infection restricted to within the collecting system. 38 children with a clinical diagnosis of urinary tract infection were studied. 26 of the patients demonstrated abnormal renal parenchymal findings with Gallium-67 Citrate or Tc-99m Glucoheptonate scintigraphy. Intravenous urography was notably ineffective with only 5 of the 20 interpreted as abnormal due to parenchymal disease or decreased function. 11 were entirely normal while only 5 demonstrated scars or hydronephrosis. Only 10 of 17 patients demonstrated intranvesicoureteral reflux on x-ray or nuclear cystography. Ultrasound depicted 6 of 20 patients as having parenchymal abnormalities. Seven were normal. Nonspecific findings such as dilitation of the renal pelvis or renal enlargement was noted in 11 of the 20 patients. Radionuclide Scintigraphy is the most efficacious modality to detect since acute bacterial nephritis.

Conway, J.J.; Weiss, S.C.; Shkolnik, A.; Yogev, R.; Firlit, C.; Traisman, E.S.

1984-01-01

425

Phenotypic plasticity in bacterial plasmids.  

PubMed Central

Plasmid pB15 was previously shown to evolve increased horizontal (infectious) transfer at the expense of reduced vertical (intergenerational) transfer and vice versa, a key trade-off assumed in theories of parasite virulence. Whereas the models predict that susceptible host abundance should determine which mode of transfer is selectively favored, host density failed to mediate the trade-off in pB15. One possibility is that the plasmid's transfer deviates from the assumption that horizontal spread (conjugation) occurs in direct proportion to cell density. I tested this hypothesis using Escherichia coli/pB15 associations in laboratory serial culture. Contrary to most models of plasmid transfer kinetics, my data show that pB15 invades static (nonshaking) bacterial cultures only at intermediate densities. The results can be explained by phenotypic plasticity in traits governing plasmid transfer. As cells become more numerous, the plasmid's conjugative transfer unexpectedly declines, while the trade-off between transmission routes causes vertical transfer to increase. Thus, at intermediate densities the plasmid's horizontal transfer can offset selection against plasmid-bearing cells, but at high densities pB15 conjugates so poorly that it cannot invade. I discuss adaptive vs. nonadaptive causes for the phenotypic plasticity, as well as potential mechanisms that may lead to complex transfer dynamics of plasmids in liquid environments. PMID:15166133

Turner, Paul E

2004-01-01

426

THE ETIOLOGY OF BACTERIAL VAGINOSIS  

PubMed Central

Bacterial vaginosis (BV) is the most common vaginal infection among women of childbearing age. This condition is notorious for causing severe complications related to the reproductive health of women. Five decades of intense research established many risk factors for acquisition of BV, however due to the complexity of BV and due to lack of a reliable animal model for this condition, its exact etiology remains elusive. In this manuscript we use a historical perspective to critically review the development of major theories on the etiology of BV, ultimately implicating BV-related pathogens, healthy vaginal microbiota, bacteriophages and the immune response of the host. None of these theories on their own can reliably explain the epidemiological data. Instead, BV is caused by a complex interaction of multiple factors, which include the numerous components of the vaginal microbial ecosystem and their human host. Many of these factors are yet to be characterized because a clear understanding of their relative contribution to the etiology of BV is pivotal to formulation of an effective treatment for and prophylaxis of this condition. PMID:21332897

Turovskiy, Yevgeniy; Noll, Katia Sutyak; Chikindas, Michael L.

2011-01-01

427

Regulation of bacterial glycogen synthesis.  

PubMed

The formation of the alpha 1,4 glucosidic linkages of bacterial glycogen occurs first by synthesis of ADPglucose from ATP and alpha glucose 1-P and then transfer of the glucose moiety from the formed sugar nucleotide to a pre-existing glucan primer. Unlike mammalian glycogen synthesis, regulation occurs at the synthesis of the sugar nucleotide. Generally glycolytic intermediates activate ADPglucose synthesis while AMP, ADP and/or Pi inhibit ADPglucose synthesis. A variation of activator specificity is is seen when the enzyme is isolated from different bacteria and is thought to be related to the predominant type of carbon assimilation or dissimilation pathways present in the particular organism. Evidence indicating that the allosteric activation effects observed in vitro are physiologically pertinent for the regulation of glycogen synthesis is reviewed. The recent experiments in identifying the allosteric activator site of the Escherichia coli ADPglucose pyrophosphorylase as well as other chemical modification studies identifying amino acid residues essential for allosteric activation and for catalytic activity are discussed. Evidence is also presented for the covalent modification of the Rhodopseudomonas sphaeroides ADPglucose pyrophosphorylase by bromopyruvate at its allosteric activator site. Regulation of the biosynthesis of glycogen also occurs at the genetic level and the current evidence for the existence of a glycogen operon is presented. In addition the current studies concerning the cloning of the DNA region containing the Escherichia coli structural genes coding for the glycogen biosynthetic enzymes as well as the nucleotide sequence of the E. coli ADPglucose pyrophosphorylase are presented. PMID:6316123

Preiss, J; Yung, S G; Baecker, P A

1983-01-01

428

Isolation and Characterization of Bacterial DNA.  

ERIC Educational Resources Information Center

An inexpensive DNA preparation is presented which starts with commercially available frozen packed bacterial cells. Methods for analyzing the DNA are also presented, along with physical chemical experiments which can be done using the purified DNA. (BB)

Wilson, W. David; Davidson, Michael W.

1979-01-01

429

Meningococcal Disease (Bacterial Meningitis) Vaccine and Pregnancy  

MedlinePLUS

... online at: www.OTISpregnancy.org . Meningococcal Disease (Bacterial meningitis) Vaccine and Pregnancy In every pregnancy, a woman ... advice from your health care professional. What is meningitis? Meningitis is an infection of the lining that ...

430

BACTERIAL IMPACTS OF OCEAN OUTFALLS: LEGAL CHALLENGES  

EPA Science Inventory

Simple analytical methods are used to help establish wastewater treatment permit conditions. However, a recent lawsuit alleged one such screening method was inadequate to show bacterial water quality standards would be protected shoreward of Honolulu's Honouliuli outfall. In resp...

431

Aquatic microenvironments in bacterial ecology and diversity  

E-print Network

Molecular surveys have revealed tremendous bacterial diversity in the world's oceans; yet how do these diverse bacteria with the same essential nutrient requirements co-exist in the same environment? This study examines ...

Hunt, Dana E., Ph. D. Massachusetts Institute of Technology

2008-01-01

432

Vaccination against salmonid bacterial kidney disease  

Technology Transfer Automated Retrieval System (TEKTRAN)

Bacterial kidney disease (BKD) of salmonid fishes, caused by Renibacterium salmoninarum, has presented challenges for development of effective vaccines, despite several decades of research. The only vaccine against BKD that is commercially licensed is an injectable preparation containing live cells ...

433

Bacterial Production Lab State variables and processes  

E-print Network

Helium nuclei Electron Gamma ray For bacterial production, 3H and 14C used. Note, 3H and 14C are weak emitters, so shielding is not required. Units: Curie, Ci: 2.2 1012 disintegrations per min (DPM) (activity

Vallino, Joseph J.

434

BACTERIAL INDICATORS OF RECREATIONAL WATER QUALITY  

EPA Science Inventory

The selection of bacterial indicators of recreational water quality are considered with respect to suggested ideal characteristics, such as association with pathogens, growth in aquatic environments, resistance to disinfection and ease of enumeration, and through the use of epide...

435

Genomic insights into bacterial DMSP transformations.  

PubMed

Genomic and functional genomic methods applied to both model organisms and natural communities have rapidly advanced understanding of bacterial dimethylsulfoniopropionate (DMSP) degradation in the ocean. The genes for the two main pathways in bacterial degradation, routing DMSP to distinctly different biogeochemical fates, have recently been identified. The genes dmdA, -B, -C, and -D mediate the demethylation of DMSP and facilitate retention of carbon and sulfur in the marine microbial food web. The genes dddD, -L, -P, -Q, -W, and -Y mediate the cleavage of DMSP to dimethylsulfide (DMS), with important consequences for ocean-atmosphere sulfur flux. In ocean metagenomes, sufficient copies of these genes are present for approximately 60% of surface ocean bacterial cells to directly participate in DMSP degradation. The factors that regulate these two competing pathways remain elusive, but gene transcription analyses of natural bacterioplankton communities are making headway in unraveling the intricacies of bacterial DMSP processing in the ocean. PMID:22457986

Moran, Mary Ann; Reisch, Chris R; Kiene, Ronald P; Whitman, William B

2012-01-01

436

Genomic Insights into Bacterial DMSP Transformations  

NASA Astrophysics Data System (ADS)

Genomic and functional genomic methods applied to both model organisms and natural communities have rapidly advanced understanding of bacterial dimethylsulfoniopropionate (DMSP) degradation in the ocean. The genes for the two main pathways in bacterial degradation, routing DMSP to distinctly different biogeochemical fates, have recently been identified. The genes dmdA, -B, -C, and -D mediate the demethylation of DMSP and facilitate retention of carbon and sulfur in the marine microbial food web. The genes dddD, -L, -P, -Q, -W, and -Y mediate the cleavage of DMSP to dimethylsulfide (DMS), with important consequences for ocean-atmosphere sulfur flux. In ocean metagenomes, sufficient copies of these genes are present for ˜60% of surface ocean bacterial cells to directly participate in DMSP degradation. The factors that regulate these two competing pathways remain elusive, but gene transcription analyses of natural bacterioplankton communities are making headway in unraveling the intricacies of bacterial DMSP processing in the ocean.

Moran, Mary Ann; Reisch, Chris R.; Kiene, Ronald P.; Whitman, William B.

2012-01-01

437

Remodeling bacterial polysaccharides by metabolic pathway engineering  

PubMed Central

Introducing structural modifications into biomolecules represents a powerful approach to dissect their functions and roles in biological processes. Bacterial polysaccharides, despite their rich structural information and essential roles in bacterium-host interactions and bacterial virulence, have largely been unexplored for in vivo structural modifications. In this study, we demonstrate the incorporation of a panel of monosaccharide analogs into bacterial polysaccharides in a highly homogenous manner via metabolic engineering of a promiscuous sugar nucleotide biosynthetic pathway. In addition, the bioorthorgonal functional groups metabolically incorporated were exploited for cell surface labeling using in vitro selective chemical ligation reactions. In summary, our study presents a general, facile and effective approach for in vivo generation of novel tailor-made bacterial polysaccharides. PMID:19251666

Yi, Wen; Liu, Xianwei; Li, Yanhong; Li, Jianjun; Xia, Chengfeng; Zhou, Guangyan; Zhang, Wenpeng; Zhao, Wei; Chen, Xi; Wang, Peng George

2009-01-01

438

Bacterial patterning controlled by light exposure.  

PubMed

Patterning of multiple bacterial strains in one system is achieved by employing a single photo-activated antibiotic. Varying the light-exposure time results in zones with mixed and single populations. PMID:25530471

Velema, Willem A; van der Berg, Jan Pieter; Szymanski, Wiktor; Driessen, Arnold J M; Feringa, Ben L

2015-01-27

439

Phylogenetic approach for inferring the origin and functional evolution of bacterial ADP-ribosylation superfamily.  

PubMed

Bacterial ADP-ribosyltransferases (BADPRTs) are extensively contributed to determine the strain-specific virulence state and pathogenesis in human hosts. Understanding molecular evolution and functional diversity of the BADPRTs is an important standpoint to describe the fundamental behind in the vaccine designing for bacterial infections. In the present study, we have evaluated the origin and functional evolution of conserved domains within the BADPRTs by analyzing their sequence-function relationship. To represent the evolution history of BADPRTs, phylogenetic trees were constructed based on their protein sequence, structure and conserved domains using different evolutionary programs. Sequence divergence and genetic diversity were studied herein to deduce the functional evolution of conserved domains across the family and superfamily. The results of sequence similarity search have shown that three hypothetical proteins (above 90%) were identical to the members of BADPRTs and their functions were annotated by phylogenetic approach. Phylogenetic analysis of this study has revealed the family members of BADPRTs were phylogenetically related to one another, functionally diverged within the same family, and dispersed into closely related bacteria. The presence of core substitution pattern in the conserved domains would determine the family-specific function of BADPRTs. Functional diversity of the BADPRTs was exclusively distinguished by Darwinian positive selection (diphtheria toxin C and pertussis toxin S) and neutral selection (arginine ADP-ribosyltransferase, enterotoxin A and binary toxin A) acting on the existing domains. Many of the family members were sharing their sequence-specific features from members in the arginine ADP-ribosyltransferase family. Conservative functions of members in the BADPRTs have shown to be expanded only within closely related families, and retained as such in pathogenic bacteria by evolutionary process (domain duplication or recombination events). Hence, we conclude that evolutionary significance of the members in the BADPRTs would provide an insight for experimental set-up on site-directed mutagenesis and vaccine engineering. PMID:23578140

Chellapandi, P; Sakthishree, S; Bharathi, M

2013-09-01

440

Phagocytosis of bacterial magnetite by leucocytes  

Microsoft Academic Search

Magnetotactic bacteria were introduced into granulocytes and monocytes by phagocytosis. The number of phagocytes containing bacterial magnetites (magneto-sensitive cells) became constant after 1.5 h incubation, and viable phagocytes contained about 20–40 cells of magnetotactic bacteria. Granulocytes and monocytes containing bacterial magnetites were separated by magnet a Samarium-cobalt from lymphocytes. After separation, 89% of lymphocytes were recovered and 95% of the

Tadashi Matsunaga; Kohji Hashimoto; Noriyuki Nakamura; Kayoko Nakamura; Shozo Hashimoto

1989-01-01

441

Plant innate immunity against human bacterial pathogens  

PubMed Central

Certain human bacterial pathogens such as the enterohemorrhagic Escherichia coli and Salmonella enterica are not proven to be plant pathogens yet. Nonetheless, under certain conditions they can survive on, penetrate into, and colonize internal plant tissues causing serious food borne disease outbreaks. In this review, we highlight current understanding on the molecular mechanisms of plant responses against human bacterial pathogens and discuss salient common and contrasting themes of plant interactions with phytopathogens or human pathogens. PMID:25157245

Melotto, Maeli; Panchal, Shweta; Roy, Debanjana

2014-01-01

442

Acute focal bacterial nephritis in 25 children  

Microsoft Academic Search

Acute focal bacterial nephritis (AFBN), formerly known as lobar nephronia, is a rare form of interstitial bacterial nephritis.\\u000a Most often described in adults with diabetes, there is only limited knowledge of AFBN in children. Ultrasound shows circular\\u000a hypoechogenic, hypoperfused parenchyma lesions, which may be misdiagnosed as a renal abscess or tumor. From 1984 to 2005,\\u000a AFBN was diagnosed in 30

Tanja Seidel; Eberhard Kuwertz-Bröking; Sigrid Kaczmarek; Martin Kirschstein; Michael Frosch; Monika Bulla; Erik Harms

2007-01-01

443

Diagnosis and treatment of bacterial diarrhea  

Microsoft Academic Search

Diarrheal illness caused by bacterial pathogens is a global health problem and remains one of the most common complaints prompting\\u000a patients to seek medical care. Strategies to increase the yield of stool culture and new rapid diagnostic tests can improve\\u000a diagnostic ability. Emerging antimicrobial resistance among the common bacterial causes of diarrhea has made treatment more\\u000a challenging. Emerging fluoroquinolone resistance

James V. Lawler; Mark R. Wallace

2003-01-01

444

Overview of bio nanofabric from bacterial cellulose  

Microsoft Academic Search

Nanofibers and bio-nonwoven fabrics of pure cellulose can be made from some bacteria such as Acetobacter xylinum. Bacterial cellulose fibers are very pure, 10?nm in diameter and about 0.5?micron long. The molecular formula of bacterial cellulose is similar to that of plant cellulose. Its fibers are very stiff and it has high tensile strength, high porosity, and nanofibrillar structure. They

Ali Ashjaran; Mohammad Esmail Yazdanshenas; Abosaeed Rashidi; Ramin Khajavi; Abbas Rezaee

2012-01-01

445

Cerebral herniation during bacterial meningitis in children  

Microsoft Academic Search

OBJECTIVE--To see whether the incidence of cerebral herniation is increased immediately after lumbar puncture in children with bacterial meningitis and whether any children with herniation have normal results on cranial computed tomography. DESIGN--Retrospective review of case notes; computed tomograms were read again. SETTING--Large paediatric teaching hospital. SUBJECTS--445 children over 30 days old admitted to hospital with bacterial meningitis. MAIN OUTCOME

G Rennick; F Shann; J de Campo

1993-01-01

446

Preparation and Characterization of Bacterial Cellulose Tube  

Microsoft Academic Search

Fermentation technique A (using oxygen-permeable tube as scaffold in fermentation vessel) and fermentation technique B (using oxygen-permeable tube as scaffold, also as fermentation vessel) were applied in preparation of bacterial cellulose (BC) tubes. Several types of oxygen-permeable tubes were tested in investigating their effects on biosynthesis of BC tubes by Gluconacetobacter xylinus. The results showed that tubular bacterial cellulose with

Shiru Jia; Weihua Tang; Hongjiang Yang; Yuanyuan Jia; Huixia Zhu

2009-01-01

447

Family dynamics and family psychotherapy of psychosomatic.  

PubMed

Family therapy of psychosomatic disorders is oftern difficult and comparable to the therapy of psychotic patients. Nonetheless, the results published today by authors such as Minuchin and Selvini and our own experiences are promising indeed. We have found that what seemed to be a deep-rooted psychic structure changed rapidly and enduringly if the relationship field changed. Amelioration of symptoms is in many cases easily attained if they are understood in their function within a relational system. Also, we regard the system or family approach as a chance for medical practice. The general practioner who usually deals with family systems has, in our view, an ideal position to bring about change if he uses his authority and trust properly. He has to obtain a positive, not pathology-oriented view and should use family and social resources in spite of engaging in an often fruitless and endless contact with the designated patient, which only serves to maintain and even to increase the homeostatic lock of the family system. PMID:550166

Wirsching, M; Stierlin, H

1979-01-01

448

Prevalence of bacterial vaginosis among women in Delhi, India  

Microsoft Academic Search

Background & objectives: Bacterial vaginosis is the most common cause of vaginal discharge among women in reproductive age. Surveillance studies on bacterial vaginosis are mostly based on specialist clinic settings. As few population-based prevalence surveys of bacterial vaginosis have been conducted, we studied the prevalence of bacterial vaginosis in the urban and rural communities in Delhi, and to associate the

P. Bhalla; Rohit Chawla; S. Garg; M. M. Singh; U. Rain; Ruchira Bhalla; Pushpa Sodhani

449

Endolymphatic sac involvement in bacterial meningitis.  

PubMed

The commonest sequelae of bacterial meningitis are related to the inner ear. Little is known about the inner ear immune defense. Evidence suggests that the endolymphatic sac provides some protection against infection. A potential involvement of the endolymphatic sac in bacterial meningitis is largely unaccounted for, and thus the object of the present study. A well-established adult rat model of Streptococcus pneumoniae meningitis was employed. Thirty adult rats were inoculated intrathecally with Streptococcus pneumoniae and received no additional treatment. Six rats were sham-inoculated. The rats were killed when reaching terminal illness or on day 7, followed by light microscopy preparation and PAS-Alcian blue staining. The endolymphatic sac was examined for bacterial invasion and leukocyte infiltration. Neither bacteria nor leukocytes infiltrated the endolymphatic sac during the first days. Bacteria invaded the inner ear through the cochlear aquaduct. On days 5-6, the bacteria invaded the endolymphatic sac through the endolymphatic duct subsequent to invasion of the vestibular endolymphatic compartment. No evidence of direct bacterial invasion of the sac through the meninges was found. Leukocyte infiltration of the sac occurred prior to bacterial invasion. During meningitis, bacteria do not invade the endolymphatic sac through the dura, but solely through the endolymphatic duct, following the invasion of the vestibular system. Leukocyte infiltration of the sac occurs prior to, as well as concurrent with bacterial invasion. The findings support the endolymphatic sac as part of an innate immune defense system protecting the inner ear from infection. PMID:24452771

Møller, Martin Nue; Brandt, Christian; Østergaard, Christian; Caye-Thomasen, Per

2015-04-01

450

Bacterial flora of conjunctiva after death  

PubMed Central

AIM To evaluate the frequency of bacterial flora of conjunctiva after death (cadaver eyes) which will give information about the bacterial contamination of donor eyes, and the in-vitro sensitivity of isolated bacteria to the commonly used antibiotics in ophthalmic practice. METHODS Conjunctival swabs were taken from the cadavers (motor vehicle accident deaths and patients who died in the hospital), within 6h after death, and sent for culture and sensitivity test. Conjunctival swabs, taken from the healthy conjunctiva of patients admitted for cataract surgery, were sent for culture and sensitivity as controls (eyes in those of living status). The bacterial isolates were tested against the commonly used antibiotics (chloramphenicol, gentamicin, ciprofloxacin) in ophthalmology practice. RESULTS Bacteria were isolated in 41 out of 100 conjunctival swabs (41%), taken from 50 cadavers (study group). Coagulase negative staphylococcus was the most common bacteria isolated (15%), followed by pseudomonas aeruginosa (5%). Gentamicin was effective against majority of the bacterial isolates (82%). Bacteria were isolated from 7 out of 100 conjunctival swabs taken as control group (eyes in living state). Coagulase negative staphylococcus was the most common organism (5%) isolated in control group; the others were staphylococcus aureus (1%) and beta hemolyticus streptococci (1%). CONCLUSION Bacteria were isolated from 41% of the cadaver eyes. High percentage sensitivity of the bacterial isolates to gentamicin (82%) supports the practice of thorough irrigation of the eyes with gentamicin solution before starting the procedure of enucleation followed by immersion of the enucleated eyeballs in gentamycin solution, to prevent the bacterial contamination. PMID:24195038

Reddy, Sagili Chandrasekhara; Paul, George

2013-01-01

451

Novel Strategies to Combat Bacterial Virulence  

PubMed Central

Purpose of review Incidences of antimicrobial resistant infections have increased dramatically over the past several decades and are associated with adverse patient outcomes. Alternative approaches to combat infection are critical, and have led to the development of more specific drugs targeted at particular bacterial virulence systems or essential regulatory pathways. The purpose of this review is to highlight the recent developments in anti-bacterial therapy and the novel approaches toward increasing our therapeutic armory against bacterial infection. Recent findings Although classic antibiotic development is not occurring rapidly, alternative therapeutics that target specific bacterial virulence systems are progressing from the discovery stage through the FDA approval process. Here we review novel antibodies that target specific virulence systems as well as a variety of newly discovered small molecules that block bacterial attachment, communication systems (quorum sensing) or important regulatory processes associated with virulence gene expression. Summary The success of novel therapeutics could significantly change clinical practice. Furthermore, the complications of collateral damage due to antibiotic administration e.g. suprainfections or decreased host immunity due to loss of synergistic bacterial communities, may be minimized using therapeutics that specifically target pathogenic behavior. PMID:18787455

Lynch, S.V.; Wiener-Kronish, J.P.

2010-01-01

452

Analysis of bacterial proteins by 2DE.  

PubMed

Two-dimensional gel electrophoresis (2DE) is a key analytical method for investigating bacterial -proteomes. The relatively simple genomes of many bacteria combined with only limited post--translational modifications of bacterial proteins mean that a significant proportion of the proteome is open to analysis by 2DE. The applications of 2DE in the field of microbiology are diverse and range from analysing physiological responses of the bacteria to environmental stress to investigating bacterial pathogenesis in human bacterial pathogens. The standard approach for 2DE in the analysis of bacterial proteins uses immobilised pH gradient (IPG) gels in the first dimension for charge separation and then an orthogonal separation, in the presence of SDS, to resolve the proteins according to their molecular mass. Protocols are presented in this chapter for small (7-cm-length IPG gel strips)- and medium (11- or 13-cm-length IPG strips)-format 2D gels using IPG gels and SDS-containing polyacrylamide slab gels for the second dimension. The application of the methods are demonstrated for the analysis of cell lysates prepared from Helicobacter pylori, although the same protocols have been used to analyse proteins from a variety of human bacterial pathogens. PMID:19381581

Cash, Philip; Argo, Evelyn

2009-01-01

453

Comprehensive Phylogenetic Analysis of Bacterial Reverse Transcriptases  

PubMed Central

Much less is known about reverse transcriptases (RTs) in prokaryotes than in eukaryotes, with most prokaryotic enzymes still uncharacterized. Two surveys involving BLAST searches for RT genes in prokaryotic genomes revealed the presence of large numbers of diverse, uncharacterized RTs and RT-like sequences. Here, using consistent annotation across all sequenced bacterial species from GenBank and other sources via RAST, available from the PATRIC (Pathogenic Resource Integration Center) platform, we have compiled the data for currently annotated reverse transcriptases from completely sequenced bacterial genomes. RT sequences are broadly distributed across bacterial phyla, but green sulfur bacteria and cyanobacteria have the highest levels of RT sequence diversity (?85% identity) per genome. By contrast, phylum Actinobacteria, for which a large number of genomes have been sequenced, was found to have a low RT sequence diversity. Phylogenetic analyses revealed that bacterial RTs could be classified into 17 main groups: group II introns, retrons/retron-like RTs, diversity-generating retroelements (DGRs), Abi-like RTs, CRISPR-Cas-associated RTs, group II-like RTs (G2L), and 11 other groups of RTs of unknown function. Proteobacteria had the highest potential functional diversity, as they possessed most of the RT groups. Group II introns and DGRs were the most widely distributed RTs in bacterial phyla. Our results provide insights into bacterial RT phylogeny and the basis for an update of annotation systems based on sequence/domain homology. PMID:25423096

Toro, Nicolás; Nisa-Martínez, Rafael

2014-01-01

454

Bacterial diversity in paclobutrazol applied agricultural soils.  

PubMed

The aim of this study was to investigate the bacterial communities on paclobutrazol [(2RS, 3RS)-1-(4-Chlorophenyl)-4, 4-dimethyl-2-(1H-1,2,4-triazol-1-yl) pentan-3-ol]-applied agricultural soils by denaturing gradient gel electrophoresis (DGGE) of polymerase chain reaction (PCR) amplified 16S rDNA gene fragments. Three different agricultural soil samples were collected from paclobutrazol applied mango and waxapple orchards, peanut fields and untreated rice fields as a control for DGGE analysis. The DGGE pattern of PCR- generated 16S rDNA gene fragments indicated that the bacterial populations from four paclobutrazol-applied soils of peanut fields were closely related to each other and two paclobutrazol-applied soils of mango and waxapple orchards harbored closely related bacterial communities. But, paclobutrazol-free agricultural soils comprised relatively a different bacterial group. However, the bacterial populations of mango and waxapple orchard are completely different from the bacterial communities of peanut field. Further purification and sequence analysis of 40 DGGE bands followed by phylogenetic tree assay showed similar results that soil bacteria from paclobutrazol applied mango and waxapple orchard are phylogenetically related. Based on the phylogenetic analysis, the clone M-4 was clad 100 % (bootstrap value) with Mycobacterium sp. The Mycobacterium sp. has been proved to degrade the phenolic compounds such as phenol, 4-chlorphenol, 2,4-dichlorophenol and paclobutrazol molecule containing chlorobenzene ring. PMID:20845182

Lin, Chorng-Horng; Kuo, Jimmy; Wang, Yen-Wen; Chen, Michael; Lin, Chin-Ho

2010-10-01

455

Glutamine versus Ammonia Utilization in the NAD Synthetase Family  

PubMed Central

NAD is a ubiquitous and essential metabolic redox cofactor which also functions as a substrate in certain regulatory pathways. The last step of NAD synthesis is the ATP-dependent amidation of deamido-NAD by NAD synthetase (NADS). Members of the NADS family are present in nearly all species across the three kingdoms of Life. In eukaryotic NADS, the core synthetase domain is fused with a nitrilase-like glutaminase domain supplying ammonia for the reaction. This two-domain NADS arrangement enabling the utilization of glutamine as nitrogen donor is also present in various bacterial lineages. However, many other bacterial members of NADS family do not contain a glutaminase domain, and they can utilize only ammonia (but not glutamine) in vitro. A single-domain NADS is also characteristic for nearly all Archaea, and its dependence on ammonia was demonstrated here for the representative enzyme from Methanocaldococcus jannaschi. However, a question about the actual in vivo nitrogen donor for single-domain members of the NADS family remained open: Is it glutamine hydrolyzed by a committed (but yet unknown) glutaminase subunit, as in most ATP-dependent amidotransferases, or free ammonia as in glutamine synthetase? Here we addressed this dilemma by combining evolutionary analysis of the NADS family with experimental characterization of two representative bacterial systems: a two-subunit NADS from Thermus thermophilus and a single-domain NADS from Salmonella typhimurium providing evidence that ammonia (and not glutamine) is the physiological substrate of a typical single-domain NADS. The latter represents the most likely ancestral form of NADS. The ability to utilize glutamine appears to have evolved via recruitment of a glutaminase subunit followed by domain fusion in an early branch of Bacteria. Further evolution of the NADS family included lineage-specific loss of one of the two alternative forms and horizontal gene transfer events. Lastly, we identified NADS structural elements associated with glutamine-utilizing capabilities. PMID:22720044

Shatalin, Konstantin; Gelfand, Mikhail S.; Osterman, Andrei L.; Sorci, Leonardo

2012-01-01

456

Glutamine versus ammonia utilization in the NAD synthetase family.  

PubMed

NAD is a ubiquitous and essential metabolic redox cofactor which also functions as a substrate in certain regulatory pathways. The last step of NAD synthesis is the ATP-dependent amidation of deamido-NAD by NAD synthetase (NADS). Members of the NADS family are present in nearly all species across the three kingdoms of Life. In eukaryotic NADS, the core synthetase domain is fused with a nitrilase-like glutaminase domain supplying ammonia for the reaction. This two-domain NADS arrangement enabling the utilization of glutamine as nitrogen donor is also present in various bacterial lineages. However, many other bacterial members of NADS family do not contain a glutaminase domain, and they can utilize only ammonia (but not glutamine) in vitro. A single-domain NADS is also characteristic for nearly all Archaea, and its dependence on ammonia was demonstrated here for the representative enzyme from Methanocaldococcus jannaschi. However, a question about the actual in vivo nitrogen donor for single-domain members of the NADS family remained open: Is it glutamine hydrolyzed by a committed (but yet unknown) glutaminase subunit, as in most ATP-dependent amidotransferases, or free ammonia as in glutamine synthetase? Here we addressed this dilemma by combining evolutionary analysis of the NADS family with experimental characterization of two representative bacterial systems: a two-subunit NADS from Thermus thermophilus and a single-domain NADS from Salmonella typhimurium providing evidence that ammonia (and not glutamine) is the physiological substrate of a typical single-domain NADS. The latter represents the most likely ancestral form of NADS. The ability to utilize glutamine appears to have evolved via recruitment of a glutaminase subunit followed by domain fusion in an early branch of Bacteria. Further evolution of the NADS family included lineage-specific loss of one of the two alternative forms and horizontal gene transfer events. Lastly, we identified NADS structural elements associated with glutamine-utilizing capabilities. PMID:22720044

De Ingeniis, Jessica; Kazanov, Marat D; Shatalin, Konstantin; Gelfand, Mikhail S; Osterman, Andrei L; Sorci, Leonardo

2012-01-01

457

Incest Family Dynamics  

Microsoft Academic Search

A self-administered questionnaire study in a self-help group for incest families focused on individual family members'perceptions of their interrelationships before and after participation in therapy. The results show that perceptions of the same relationships varied greatly among family members. Before therapy, the father-daughter relationship received the most divergent ratings,with fathers rating it as extremely good and daughters as extremely bad.

Inger J. Sagatun; Louise Prince

1989-01-01

458

Neighborhoods and Families  

Microsoft Academic Search

\\u000a Neighborhoods have a profound impact on children and their families, including health and safety, educational attainment,\\u000a child maltreatment risk, and many others. Yet, surprisingly little is known about the specific mechanisms through which neighborhood\\u000a physical and social characteristics features influence child and family outcomes. This chapter looks at current definitions\\u000a for community and family and reviews research for community effects

James R. McDonell

459

The family and HIV.  

PubMed Central

The impact of HIV and AIDS on the family is described, with particular focus on the situation where the child is the first member of the family to be diagnosed. The results of the social stigma, the effect on relationships together with the global, economic and cultural aspects of the disease make it unique. These issues are discussed and an integrated approach to confidentiality, the provision of services for families and involvement of the community is described. PMID:1743706

Gibb, D M; Duggan, C; Lwin, R

1991-01-01

460

Households and Families  

NSDL National Science Digital Library

The US Census Bureau has released a report which demonstrates that "traditional families" (married couples with children) have begun to stabilize as a percentage of all families in the 1990s, and the growth of single-parent families has slowed. Most of the information in the report comes from the March 1997 Current Population Survey. Users may download the full report as well as detailed tables in .pdf format.

Bryson, Ken.

1998-01-01

461

Favorite Family Traditions  

NSDL National Science Digital Library

Students use the text The Relatives Came by Cynthia Rylant as a springboard for discussion about family traditions. After identifying the traditions observed by the relatives, students meet in small groups to brainstorm new traditions that could arise from the families gathering together during the winter. The lesson is concluded by having each student write about their own favorite family tradition and share it with a small group.

2012-12-08

462

Bacterial Catabolism of Dimethylsulfoniopropionate (DMSP)  

PubMed Central

Dimethylsulfoniopropionate (DMSP) is a metabolite produced primarily by marine phytoplankton and is the main precursor to the climatically important gas dimethylsulfide (DMS). DMS is released upon bacterial catabolism of DMSP, but it is not the only possible fate of DMSP sulfur. An alternative demethylation/demethiolation pathway results in the eventual release of methanethiol, a highly reactive volatile sulfur compound that contributes little to the atmospheric sulfur flux. The activity of these pathways control the natural flux of sulfur released to the atmosphere. Although these biochemical pathways and the factors that regulate them are of great interest, they are poorly understood. Only recently have some of the genes and pathways responsible for DMSP catabolism been elucidated. Thus far, six different enzymes have been identified that catalyze the cleavage of DMSP, resulting in the release of DMS. In addition, five of these enzymes appear to produce acrylate, while one produces 3-hydroxypropionate. In contrast, only one enzyme, designated DmdA, has been identified that catalyzes the demethylation reaction producing methylmercaptopropionate (MMPA). The metabolism of MMPA is performed by a series of three coenzyme-A mediated reactions catalyzed by DmdB, DmdC, and DmdD. Interestingly, Candidatus Pelagibacter ubique, a member of the SAR11 clade of Alphaproteobacteria that is highly abundant in marine surface waters, possessed functional DmdA, DmdB, and DmdC enzymes. Microbially mediated transformations of both DMS and methanethiol are also possible, although many of the biochemical and molecular genetic details are still unknown. This review will focus on the recent discoveries in the biochemical pathways that mineralize and assimilate DMSP carbon and sulfur, as well as the areas for which a comprehensive understanding is still lacking. PMID:21886640

Reisch, Chris R.; Moran, Mary Ann; Whitman, William B.

2011-01-01

463

Bacterial Catabolism of Dimethylsulfoniopropionate (DMSP).  

PubMed

Dimethylsulfoniopropionate (DMSP) is a metabolite produced primarily by marine phytoplankton and is the main precursor to the climatically important gas dimethylsulfide (DMS). DMS is released upon bacterial catabolism of DMSP, but it is not the only possible fate of DMSP sulfur. An alternative demethylation/demethiolation pathway results in the eventual release of methanethiol, a highly reactive volatile sulfur compound that contributes little to the atmospheric sulfur flux. The activity of these pathways control the natural flux of sulfur released to the atmosphere. Although these biochemical pathways and the factors that regulate them are of great interest, they are poorly understood. Only recently have some of the genes and pathways responsible for DMSP catabolism been elucidated. Thus far, six different enzymes have been identified that catalyze the cleavage of DMSP, resulting in the release of DMS. In addition, five of these enzymes appear to produce acrylate, while one produces 3-hydroxypropionate. In contrast, only one enzyme, designated DmdA, has been identified that catalyzes the demethylation reaction producing methylmercaptopropionate (MMPA). The metabolism of MMPA is performed by a series of three coenzyme-A mediated reactions catalyzed by DmdB, DmdC, and DmdD. Interestingly, CandidatusPelagibacter ubique, a member of the SAR11 clade of Alphaproteobacteria that is highly abundant in marine surface waters, possessed functional DmdA, DmdB, and DmdC enzymes. Microbially mediated transformations of both DMS and methanethiol are also possible, although many of the biochemical and molecular genetic details are still unknown. This review will focus on the recent discoveries in the biochemical pathways that mineralize and assimilate DMSP carbon and sulfur, as well as the areas for which a comprehensive understanding is still lacking. PMID:21886640

Reisch, Chris R; Moran, Mary Ann; Whitman, William B

2011-01-01

464

Families Without Fathers  

ERIC Educational Resources Information Center

Common generalizations about children growing up in fatherless families are reexamined. Topics include school achievement, delinquency, masculine identity, role of the mother, and societal attitudes. (NH)

Herzog, Elizabeth; Sudia, Cecelia E.

1972-01-01

465

Understanding Fragile Families  

MedlinePLUS

... school performance. The research showed similar effects of relationship transitions on aggressive, depressive, and withdrawal behaviors. Contrary to expectations that access to college promotes family stability and ...

466