Top PDF Bacteria, phages and septicemia.

Bacteria, phages and septicemia.

Bacteria, phages and septicemia.

Phages were detected in 91 out of 150 culture supernatants (Table 1) ranging from 10 to 10 7 PFU/ml. Plaques appeared only on one indicator strain in about half of the cases, suggesting that a larger indicator set could result in the detection of more phage- producing strains. Three virus-producing clones were tested for the type of phage or phages released for all four bacterial strains using the sensitivity pattern of the indicator strains. Only a single pattern was detected in most of the test cases. These data indicate that the bacterial clones released one or only a few types of phages. We next tested if antibiotics commonly used to treat septicemic infections could induce plaque formation in clinical bacterial isolates. We selected five strains (3 Ec and 2 Sa) that did not produce plaques spontaneously but did so after treatment with MitC or UV, to test this idea. Indicator strains (one indicator strain per bacterial isolate) were selected based on data from the experiment described above. We did not observe plaque formation when the cells were treated with tobramycin. However, cipro- floxacin induced phage release from one of the Sa strains. It has been shown previously that ciprofloxacin treatment causes prophage induction (and virulence modulation) in S. aureus from patients with cystic fibrosis [16] as well as in shiga-toxin producing E. coli strains of human origin [17–19]. In some cases, like infections with enterohemorrhagic E. coli O157:H7, antibiotic treatment is controversial because of prophage induction, in- creasing the risk of the hemolytic-uremic syndrome [18,20].
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Characterization of modular bacteriophage endolysins from Myoviridae phages OBP, 201φ2-1 and PVP-SE1.

Characterization of modular bacteriophage endolysins from Myoviridae phages OBP, 201φ2-1 and PVP-SE1.

Previously, Briers and co-workers [6] revealed the insensitivity of Gram-positive bacteria for the muralytic action of modular endolysins KZ144 and EL188. We found that also OBPgp279, PVP-SE1gp146 and 201Q2-1gp229 leave the Gram-positive bacteria S. aureus subsp. aureus Rosenbach ATCC 6538, M. lysodeikticus ATCC 4698, L. lactis subsp. lactis and B. subtilis PSB3 unharmed. An explanation must be found in the structure of their PG layer. Sensitive Gram-negative species share a common A1c chemotype of PG with a direct peptide bond between adjacent muropeptides, whereas insensitive S. aureus subsp. aureus Rosenbach ATCC 6538, M. lysodeikticus ATCC 4698 and L. lactis subsp. lactis have a PG of the A3a, A2a and A4a chemotype, respectively [31,32]. These last 3 chemotypes show resistance for the mode of action of muralytic enzymes, like HEWL, due to the absence of a direct inter-peptide cross-link [33]. Bacillus subtilis PSB3, however, possesses the A1c chemotype of its Gram-negative counterparts but 17.3% of the glucosamine sugars in its PG are N-deacetylated [34]. As previously shown for commercial HEWL, this species-specific modification explains for the resistance against PG lytic enzymes [33]. Therefore, a direct cross-linked A1c chemotype of PG without substantial N-deacetylation is an essential prerequisite for efficient hydrolysis by endolysins from Gram-negative infecting phages.
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CHARACTERIZATION AND LYTIC ACTIVITY OF PSEUDOMONAS FLUORESCENS PHAGES FROM SEWAGE Ananthi Radhakrishnan

CHARACTERIZATION AND LYTIC ACTIVITY OF PSEUDOMONAS FLUORESCENS PHAGES FROM SEWAGE Ananthi Radhakrishnan

Seven phages were isolated from sewage enrichment process, whereas isolation of phages from soil samples was found to be unsuccessful. The results are in concordance with an earlier study wherein the phages of Pseudomonas were successfully isolated only from water samples, while in soil and feces no Pseudomonas specific phages were detected (22).Earlier studies attribute similar results to relatively low viable counts of phage capable of infecting specific bacteria (6), relatively low rates of phage diffusion within soil, particularly under drier conditions (18) and relatively high rates of free-phage inactivation within soil (27). There have been a number of reports of phage presence, in various environments (14,2). However, it is uncertain how those phages from sewage have impact on bacterial populations in soil environment. The susceptibility analysis of soil bacterial isolates in this study shows the soil bacterial population was resistant to these phage isolates. It is interesting to note that soil bacterial isolates obtained within the vicinity of sewage treatment plant showed
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Antimicrobial assessment of phages entrapped in bio-based structures

Antimicrobial assessment of phages entrapped in bio-based structures

Food industry is one of the most important industries in the world, with great relevance for human health. To ensure and improve food safety and quality, new technologies arise every day. New approaches appear to reduce consumer’s health risks and to comply sanitary legislation, for national and international markets. Health safety is one of the major concerns of the present and future. Currently, one in ten people become sick due to food contaminations with pathogens, specialy pathogenic bacteria such as: Salmonella, Listeria, Escherichia coli and Campylobacter. Deaths resulting from food poisoning are alarming, reaching values of 420 000 deaths per year . Smart packaging trough the development of new methodologies and with the combination of different systems (e.g modified and controled atmosphere, incorporation of functional compounds) is a promising solution for food related health problems, since they are able to ensure the quality, traceability (allow pathogen identification in the moment of consumption) and safety (avoiding microbial growth), allowing their transportation all around the world any time of year. Recently, consumers changed their demands, not only about safe products, but also with their sources and their functional properties. Today, the regular consumer desires natural food products, with no chemical additives and slightly processed, and at the same time that are ready for consumption and easily prepared (Gouvêa, Mendonça, Soto, & Cruz, 2015). Smart and active packaging market is growing each year, and due to the major advantages related to food quality and safety, it is expected to become a field of major impact in food industry and consequently more explored.
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Avaliação de eventos infecciosos oportunistas em crianças portadoras de leucemias.

Avaliação de eventos infecciosos oportunistas em crianças portadoras de leucemias.

The main malignant neoplasm that affects children and adolescents is leukemia, in particular acute leukemias. The clonal hyper- proliferation of hematopoietic precursors combined with anti- neoplastic therapy leads to a variable degree of immunological involvement with a consequent increase in susceptibility to opportunistic infections. The objective of this work was to describe the frequency of leukemia and the major opportunistic infections in children and adolescents in the region of Passo Fundo, Brazil. In this retrospective cohort study, of cases from January 2000 to December 2007, 92 patients aged between 8 months to 17 years were reviewed. Seventy-two cases of ALL, 18 of AML and 2 of LMC (78.2%, 19.6% and 2.2%, respectively) were found. The commonest infectious disease was pneumonia, followed by septicemia (the leading cause of death). Bacteria, accounting for 52.4% of infections, were the most frequent microorganisms isolated with parasitic, viral and fungal diseases accounting for 20.6%, 19.0% and 7.9% of infections, respectively. The results of this study confirm that opportunistic diseases are the main complications of leukemia and increase the morbid-mortality of these patients. Rev. Bras. Hematol. Hemoter. 2009;31(2):74-79.
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Use of newly isolated phages for control of Pseudomonas aeruginosa PAO1 and ATCC 10145 biofilms

Use of newly isolated phages for control of Pseudomonas aeruginosa PAO1 and ATCC 10145 biofilms

It is not surprising that phage infection in planktonic cells is more efficient than in biofilms due to biofilm architecture, which prevents easy access by phages to the bacteria (Hanlon et al., 2001). Due to the inefficient activity of phages phiIBB- PACL12 and phiIBB-PAC23 against planktonic cultures, only two phages, phiIBB-PAA2 and phiIBB-PAP21, were chosen for P. aeruginosa biofilm control experiments. Both phages, tested against 24 h biofilms, caused significant reduction on biofilm cells already after 2 h of infection and the reduction was further enhanced after 6 h of biofilm treatment, reaching a reduction of almost 3 log by phage phiIBB-PAP21 and a 2 log reduction by phage phiIBB-PAA2. Although our approach was different, viable cell reductions achieved were similar to those reported by Fu et al., where P. aeruginosa phages were used to prevent biofilm formation on hydrogel-coated catheter surfaces. Accordingly, Fu et al., after 24 h, achieved a 2.84-log lower number of viable cells on phage pre-treated catheters than on untreated catheters (Fu et al., 2010).
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Magda Atilano Tese.pdf

Magda Atilano Tese.pdf

________________________________________________________________________  represented  as  the  median  (with  25%  and  75%  inter‐quartile  range).  WGA  binding  to  bacteria  treated  with  increased  tunicamycin  concentrations  increases  as  the  levels  of  WTA  are  reduced.  Grey  panels  are  phase‐contrast  images  of  bacterial  cells  (white  scale  bar  represents  1  μm),  and  black  panels  show  WGA  (WGA‐Alexa Fluor 488 conjugate) binding to the bacteria surface (PGN) GlcNAc  residue,  DNA  (stained  with  Hoechst  33342)  and  a  merge  of  the  last  channels  (Overlay); yellow arrowheads highlight lectin WGA binding to the cell surface of  the  bacteria.  Kruskal‐Wallis  analysis  followed  by  Dunn’s  multiple  comparison  post‐test, revealed significant differences in the binding for treated and untreated  bacteria  (P  <  0.05)  (B)  Electrophoresis  gel  analysis  of  WTAs  extracted  from  overnight  culture  of  S.  aureus  NCTC8325‐4  strain  treated  with  varying  tunicamycin  concentrations  and  NCTCΔtagO,  WTA  production  is  virtually  abolished with 0.16 μg/ml tunicamycin.  Treated cells with 16 μg/ml can recover  WTA synthesis if cells were grown in fresh TSB without tunicamycin.  
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Concentração inibitória mínima de oxitetraciclina para isolados de Aeromonas Hydrophila obtidos de diferentes fontes.

Concentração inibitória mínima de oxitetraciclina para isolados de Aeromonas Hydrophila obtidos de diferentes fontes.

Objetivou-se com este trabalho determinar a concentração inibitória mínima (MIC) de oxitetraciclina para isolados de Aeromonas hydrophila obtidos de pescado, água de cultivo de peixes e casos de septicemia hemorrágica em peixes. Foi determinado MIC de 100 isolados de A. hydrophila, oriundos de 12 pisciculturas localizadas nos Estados de Minas Gerais, Rio de Janeiro e Rio Grande do Sul, utilizando a técnica de macrodiluição em caldo. Os resultados demonstraram que 14 isolados apresentaram MIC>100 µg/mL (resistentes) e 86 apresentaram MIC<12,5 µg/mL (sensíveis). Não houve diferença entre os isolados de pescado, caso clínico e água de cultivo. Conclui-se que a variação demonstrada pode representar um risco de seleção de linhagens bacterianas resistentes em ambientes aquáticos devido ao uso de oxitetraciclina.
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Facultative extremophilic bacteria in brazilian agricultural soils  / Bactérias extremofílicas facultativas em solos agrícolas brasileiros

Facultative extremophilic bacteria in brazilian agricultural soils / Bactérias extremofílicas facultativas em solos agrícolas brasileiros

This study demonstrated that in all soil samples studied it was possible to determine four groups of facultative extremophiles, which is not common in soil plant pathogenic bacteria. Usually plant pathogenic bacteria grow under temperatures ranging from 25ºC to 40ºC (mesophilic bacteria), since higher temperatures cause desiccation in the bacteria cells (Bedendo, 1995); pH close to neutrality (6.5 to 7.5); and salt concentration no above 5% NaCl. Nascimento et al. (2005) for instance, reported that the phytopathogenic Xanthomonas campestris pv. viticola decreased after 3.0% of NaCl, being 6.0% a lethal concentration. According to the authors, high concentrations of NaCl make the environment outside the bacterial cell hypertonic forcing a release of cell’s water from the plasma membrane, consequently inhibiting the bacterial growth.
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Effects of manure compost application on soil microbial community diversity and soil microenvironments in a temperate cropland in China.

Effects of manure compost application on soil microbial community diversity and soil microenvironments in a temperate cropland in China.

For bacterial community structure, all the fertilizers stimulated the generation of band numbers 1–6. N, B or NB treatments stimulated the occurrence of bands A–-D, whereas M or MB enhanced the bands a–c at the seeding stage. The influences from N, B or NB treatment on bacterial community structure were lower than those from M or MB treatment (Fig. 4). The number of DGGE bands was the highest at the tasseling stage, indicating that the formed microbial community was the most diverse at this stage. We therefore confirmed that the largest influences of bacteria community structure occurred after the fertilizer treat- ments of M and MB. The results at the mature stage were similar to the tasseling stage, e.g., the influences on bacterial community structure from the M or MB treatments were higher than that of the N or NB treatments (Fig. 4B and 4C). Furthermore, statistical analysis showed that manure compost and bacterial fertilizer could enhance the Shannon index, whereas the N and NB treatment decreased the Shannon index, especially from seeding stage to Figure 5. DGGE banding patterns of 18S rDNA fungi fragment and clustering of DGGE profiles in various treatments during maize growth stages. CK: no fertilizer; N: N fertilizer; B: bacteria fertilizer; NB: N fertilizer + bacteria fertilizer; M: manure compost; MB: manure compost + bacteria fertilizer.
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Avaliação dos óbitos e necropsias em pacientes internados em um serviço de reumatologia pediátrica por um período de dez anos.

Avaliação dos óbitos e necropsias em pacientes internados em um serviço de reumatologia pediátrica por um período de dez anos.

Objetivo: correlacionar os dados clínicos do óbito com achados de necropsia em pacientes internados em uma unidade de reumatologia pediátrica. Métodos: o estudo é uma coorte histórica. Em dez anos, no período compreendido entre janeiro de 1994 e dezembro de 2003, ocorreram 57.159 internações com 1.907 (3%) óbitos no Instituto da Criança. Destas internações, 548 (1%) apresentaram doenças reumáticas ou pediátricas e foram acompanhadas pela Unidade de Reumatologia Pediátrica, incluindo 348 pacientes. Os óbitos e as necropsias foram analisados e a classificação de Goldman foi utilizada para detectar discordância entre o diagnóstico clínico do óbito e a necropsia. Resultados: no período do estudo, 34 (10%) pacientes evoluíram para óbito. As principais doenças asso- ciadas ao óbito foram: lúpus eritematoso sistêmico juvenil ( LESJ ) em 18 pacientes (53%) e artrite idiopática juvenil ( AIJ ) em sete casos (21%). Necropsias foram realizadas em 21 pacientes (64% dos óbitos). Nos 18 casos de LESJ , a atividade da doença esteve presente em 16 casos, sendo associada à septicemia em 15 deles. Discordância entre o diagnóstico clínico e necropsia foi evidenciada em seis casos com LESJ : três com infecções fúngicas, um com tuberculose, um com nefrite proliferativa difusa e outro com aterosclerose. Sete pacientes com AIJ evoluíram para óbito: septicemia em quatro e síndrome de ativação macrofágica em três. Em um caso de AIJ foi diagnosticado, exclusivamente na necropsia: linfoma de Hodgkin, aterosclerose e infarto anterior do miocárdio. Conclusões: a freqüência de óbitos foi 10% e necropsia evidenciou doença infecciosa, aterosclerose ou neoplasia não diagnosticadas previamente. A necropsia é importante
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Braz. Dent. J.  vol.23 número5

Braz. Dent. J. vol.23 número5

A similar prevalence of S. mutans was detected in the two groups (23.0% vs 30.7%). The high frequency of S. mutans found in samples of group BS differs from the results of Slots (6), who found that S. mutans was only detected in 5% of samples of biofilm from black stains. Slots (6) detected a correlation between the low number of S. mutans and the low rate of caries associated to the presence of black stains. However, Reid and Beeley (11) suggested that the reduction of the incidence of caries in individuals with black extrinsic tooth stains is due to the calcium and phosphate content of the biofilm of the stain. Analyzing the biofilm of black extrinsic tooth stains, some authors found a positive correlation between the presence of stains and the low incidence of caries (2,12). However, other studies (13,14) did not find such a correlation. The discordant findings can be related to the multifactorial nature of caries disease and the hypothesis that the positive correlation between the presence of black stains and the low incidence of caries is a simplistic and unifactorial evaluation. In a review of the fundamentals about black stains, its diagnosis and possible differential diagnoses, microbiology and therapy, Ronay and Attin (15) concluded that the reasons why the results are not clear about the black Figure 1. Bacteria-positive samples of patients with (A) or without
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Review of semiochemicals that mediate the oviposition of mosquitoes: a possible sustainable tool for the control and monitoring of Culicidae

Review of semiochemicals that mediate the oviposition of mosquitoes: a possible sustainable tool for the control and monitoring of Culicidae

Identification of semiochemicals involved in the selection of oviposition sites. At first several studies performed different experiments trying to evaluate the influence of physic-chemical factors in the oviposition, such as light reflection, odor, temperature, humidity, substrate texture and other breeding sites’ features (Gjullim 1961, Gjullim et al. 1965, Fay & Perry 1965, Perry & Fay 1967). Yet, the first scientists to erect a hypothesis concerning the existence of a pheromone that should stimulate oviposition in mosquitoes were Hudson & Mclintock (1967). Later, Osgood (1971) verified this hypothesis studying the behavior of gravid females of Culex tarsalis Coquillet which displayed a preference to lay eggs in water with conspecific larvae, instead of distilled water. With the
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Functional alignment of regulatory networks: a study of temperate phages.

Functional alignment of regulatory networks: a study of temperate phages.

As a case study, we considered the regulatory networks of two well-characterized temperate bacteriophages of E. coli, k and 186 (Figure 1). These two phages represent two distinct classes of temperate bacteriophages: the lambdoid phages— which include k, P22, 434, HK97, and HK022, and the P2 group—which includes P2, 186, HP1, K139, and PSP3. k and 186 are not detectably related in sequence and have different genome organizations. Using tBLASTx [6] to compare all of the reading frames, there are only two clearly homologous protein pairs: the k endolysin R/186 (E-score ¼ 10 34 ) and a pair of early lytic proteins of unknown function (E-score ¼ 2 3 10 4 ). No significant similarity was detectable at the nucleotide level (using BLASTn, [6]). On the genome level, the arrangement of genes, promoters, and operators is very different [7–10]. As a control of methodology, we also considered the P22 phage, which, as a member of the lambdoid family, allows us to compare topologies of evolutionarily related networks.
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Plant growth-promoting bacteria as inoculants in agricultural soils

Plant growth-promoting bacteria as inoculants in agricultural soils

The excretion of siderophores by bacteria might stim- ulate plant growth, thereby improving nutrition (direct ef- fect) or inhibiting the establishment of phytopathogens (indirect effect) through the sequestration of Fe from the environment. Unlike microbial pathogens, plants are not affected by bacterial-mediated Fe depletion, and some plants can even capture and utilize Fe 3+ -siderophore bacte- rial complexes (Dimkpa et al., 2009b). The role of endo- phytic siderophore-producing bacteria has been rarely studied; however, the ability to produce siderophores con- fers competitive advantages to endophytic bacteria for the colonization of plant tissues and the exclusion of other mi- croorganisms from the same ecological niche (Loaces et al., 2011). These authors observed that the community of endophytic siderophore-producing bacteria associated to rice roots is richer than those from the soil at the tillering and grain-filling stages. Endophytic bacterial strains be- longing to genus Burkholderia showed preferential local- ization inside rice plants, and their role may be relevant to prevent the infection of young plants by Sclerotium oryzae and Rhizoctonia oryzae.
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Recombinant phages for Spodoptera frugiperda control: new perspectives to tackle an economic problem / Fagos recombinantes para o controle de Spodoptera frugiperda: novas perspectivas para enfrentar um problema econômico

Recombinant phages for Spodoptera frugiperda control: new perspectives to tackle an economic problem / Fagos recombinantes para o controle de Spodoptera frugiperda: novas perspectivas para enfrentar um problema econômico

We used the biopanning strategy in order to select phages displaying peptides able to bind to S. frugiperda midgut proteins insecticidal activity. Based on the objectives of this work, the ELISA test was crucial for the validation of the selection process, as well as for the identification of promising clones. This technique demonstrated the affinity to the target and not only the numbers of viral particles. Ngubane, Gresh [55] used the same validation technique, allowing the identification of specific peptides for mycobacteria. This immunoassay was also previously performed to demonstrate the reactive phage particles to the desired target by [56, 57]. Considering our results, the process was successful, since we selected seven clones reactive to the target, compared to the M13 wild-type phage, a filamentous virus that does not express external peptide fused to protein III. At the end of the selection process, we obtained seven promising phage clones capable of specifically recognize midgut proteins of S. frugiperda. This reactivity was further confirmed by the immunohistochemistry assay. Throughout the bioinformatics analysis, no protein structural motif was identified during the alignment of the sequences of the seven clones. This result was expected because we used a conformational library for biopanning process. This library is particularly interesting because allows the selection of peptides with different conformations, which can interact with different midgut proteins.
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Gingerol e Gingerol modulam as alterações renais promovidas por modelo  de septicemia em ratos

Gingerol e Gingerol modulam as alterações renais promovidas por modelo de septicemia em ratos

A lesão renal aguda (LRA) é uma das manifestações mais críticas durante o evento séptico, manifestando-se por produção de espécies reativas de oxigênio, alterações glomerulares e tubulares, que contribuem para a piora do prognóstico e diminuição da sobrevida. Os compostos fenólicos [6]-gingerol e [10]-gingerol são substâncias bioativas do gengibre (Zingiber officinale Roscoe) que por meio de suas propriedades antioxidantes, antiflamatórias e metabólicas possuem um grande potencial para a renoproteção. O presente estudo investigou os efeitos moduladores dos compostos [6]- e [10]-gingerol diante ao dano renal desencadeado pelo modelo polimicrobiano cecal ligation and puncture (CLP) de sepse. Foram utilizados ratos Wistar (180-210 g) divididos em 6 grupos (protocol. 45/14). Os grupos controles Sham [grupos: I., II. e III.] foram induzidos à falsa cirurgia e subsequentemente tratados com tween-80 2%, com [6]-gingeol ou [10]-gingerol (25 mg/kg); grupos induzidos LRA [grupos: IV., V. e VII.] por meio do processo cirugico CLP e subsequentemente tratados com tween-80 2%, [6]-, ou [10]-gingerol (25 mg/kg). Os tratamentos foram realizados 2 horas pré e, por 12 e 24 após indução. Foram avaliados os parâmetros bioquímicos indicativos de função renal, função tubular, perfil oxidativo, atividade antioxidante e a transcrição gênica de mediadores pró-inflamatórios através de RT-PCR, análise histopatológica e taxa de sobrevida, além do perfil metabolômico por meio de ensaios por Resonância Magnética Nuclear (RMN) de 1 H. A infecção polimicrobiana modificou de forma considerável os parâmetros relacionados à função renal. Observou-se uma diminuição do clearance de creatinina (CL CR) (0,4±0,1 mL/min), do fluxo urinário (FU)
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Evaluation of different detection methods of biofilm formation in the clinical isolates

Evaluation of different detection methods of biofilm formation in the clinical isolates

Background: Microorganisms growing in a biofilm are associated with chronic and recurrent hu- man infections and are highly resistant to antimicrobial agents. There are various methods to detect biofilm production like Tissue Culture Plate (TCP), Tube method (TM), Congo Red Agar meth- od (CRA), bioluminescent assay, piezoelectric sensors, and fluorescent microscopic examination. Objective: This study was conducted to compare three methods for the detection of biofilms. Method: The study was carried out at the Department of Microbiology, Army Medical College, National University of Sciences and Technology, Pakistan, from January 2010 to June 2010. A total of 110 clinical isolates were subjected to biofilm detection methods. Isolates were identified by standard microbiological procedures. Biofilm detection was tested by TCP, TM and CRA. Antibiotic suscep- tibility test of biofilm producing bacteria was performed by using the Kirby-Bauer disc diffusion technique according to CLSI guidelines. Results: The TCP method was considered to be superior to TM and CRA. From the total of 110 clinical isolates, TCP method detected 22.7% as high, 41% mod- erate and 36.3% as weak or non-biofilm producers. We have observed higher antibiotic resistance in biofilm producing bacteria than non-biofilm producers. Conclusion: We can conclude from our study that the TCP method is a more quantitative and reliable method for the detection of biofilm forming microorganisms as compared to TM and CRA methods, and it can be recommended as a general screening method for detection of biofilm producing bacteria in laboratories.
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Prevalence and evolution of core photosystem II genes in marine cyanobacterial viruses and their hosts.

Prevalence and evolution of core photosystem II genes in marine cyanobacterial viruses and their hosts.

Phages are listed by their name, followed by their original host. Phages that are known to infect both Prochlorococcus and Synechococcus hosts are indicated with a ‘‘D’’; those that infect only one genus are labeled either P (infect only Prochlorococcus hosts) or S (infect only Synechococcus hosts), while those that are unknown are designated with a ‘‘?’’. Phages shown in italics and bracketed with ‘‘**’’ were isolated on hosts that do not belong to the same cluster and are thus exceptions to the general clustering pattern (see text). Taxa are color coded according to the following biological groupings: myoviruses (red), podoviruses (black), marine Synechococcus hosts (light blue), marine Prochlorococcus hosts (dark green, LL; light green, HL), freshwater cyanobacteria (dark blue). The tree topology was estimated by LogDet analysis of 1st and 2nd codon positions. Sequences where intragenic recombination was detected using other methods (see Materials and Methods) were not included in these phylogenetic analyses. Branch lengths were estimated by maximum likelihood under a model with nonstationary nucleotide frequencies. Numbers at the nodes represent neighbor-joining bootstrapping and maximum likelihood puzzling support. Anab, Anabaena; Gloe, Gleobacter; HL, high-light adapted; LL, low-light adapted; Syncy, Synechocystis; Thermo, Thermosynechococcus.
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Veterinary survey in Mexico, Central America and Colombia: A Summary

Veterinary survey in Mexico, Central America and Colombia: A Summary

To those who are acquainted with animal disease problems in Latin Ameritan countries, it is not surprising to find that anthrax, blackleg and hemorrhagic septicemia (p[r]

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