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Treating plant bacterial diseases is notoriously difficult because of the lack of available antimicrobials. Pseudomonas syringae pathovar syringae (Pss) is a major pathogen of cherry (Prunus avium) causing bacterial canker of the stem, leaf and fruit, impacting productivity and leading to a loss of trees. In an attempt to find a treatment for this disease, naturally occurring bacteriophage (phage) that specifically target Pss is being investigated as a biocontrol strategy. However, before using them as a biocontrol treatment, it is important to both understand their efficacy in reducing the bacterial population and determine if the bacterial pathogens can evolve resistance to evade phage infection. To investigate this, killing curve assays of five MR phages targeting Pss showed that phage resistance rapidly emerges in vitro, even when using a cocktail of the five phages together. To gain insight to the changes occurring, Pss colonies were collected three times during a 66-h killing curve assay and separately, Pss and phage were also coevolved over 10 generations, enabling the measurement of genomic and fitness changes in bacterial populations. Pss evolved resistance to phages through modifications in lipopolysaccharide (LPS) synthesis pathways. Bacterial fitness (growth) and virulence were affected in only a few mutants. Deletion of LPS-associated genes suggested that LPS was the main target receptor for all five MR phages. Later generations of coevolved phages from the coevolution experiment were more potent at reducing the bacterial density and when used with wild-type phages could reduce the emergence of phage-resistant mutants. This study shows that understanding the genetic mechanisms of bacterial pathogen resistance to phages is important for helping to design a more effective approach to kill the bacteria while minimizing the opportunity for phage resistance to manifest.
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Doenças das Plantas , Pseudomonas syringae , Pseudomonas syringae/virologia , Pseudomonas syringae/genética , Doenças das Plantas/microbiologia , Fagos de Pseudomonas/genética , Fagos de Pseudomonas/fisiologia , Bacteriófagos/genética , Bacteriófagos/fisiologiaRESUMO
Plastics, due to their varied properties, find use in different sectors such as agriculture, packaging, pharmaceuticals, textiles, and construction, to mention a few. Excessive use of plastics results in a lot of plastic waste buildup. Poorly managed plastic waste (as shown by heaps of plastic waste on dumpsites, in free spaces, along roads, and in marine systems) and the plastic in landfills, are just a fraction of the plastic waste in the environment. A complete picture should include the micro and nano-plastics (MNPs) in the hydrosphere, biosphere, lithosphere, and atmosphere, as the current extreme weather conditions (which are effects of climate change), wear and tear, and other factors promote MNP formation. MNPs pose a threat to the environment more than their pristine counterparts. This review highlights the entry and occurrence of primary and secondary MNPs in the soil, water and air, together with their aging. Furthermore, the uptake and internalization, by plants, animals, and humans are discussed, together with their toxicity effects. Finally, the future perspective and conclusion are given. The material utilized in this work was acquired from published articles and the internet using keywords such as plastic waste, degradation, microplastic, aging, internalization, and toxicity.
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Microplásticos , Plásticos , Animais , Humanos , Plásticos/toxicidade , Microplásticos/toxicidade , Têxteis , Envelhecimento , AgriculturaRESUMO
Evaluation of resistant profiles and detection of antimicrobial-resistant genes of bacterial pathogens in the nonclinical milieu is imperative to assess the probable risk of dissemination of resistant genes in the environment. This paper sought to identify antibiotic-resistant genes in Pseudomonas aeruginosa from nonclinical sources in Mthatha, Eastern Cape, and evaluate its public health implications. Samples collected from abattoir wastewater and aquatic environment were processed by membrane filtration and cultured on CHROMagarTM Pseudomonas medium. Species identification was performed by autoSCAN-4 (Dade Behring Inc., IL). Molecular characterization of the isolates was confirmed using real-time polymerase chain reaction (rPCR) and selected isolates were further screened for the possibility of harboring antimicrobial resistance genes. Fifty-one Pseudomonas species were recovered from abattoir wastewater and surface water samples, out of which thirty-six strains were Pseudomonas aeruginosa (70.6%). The P. aeruginosa isolates demonstrated resistance to aztreonam (86.1%), ceftazidime (63.9%), piperacillin (58.3%), cefepime (55.6%), imipenem (50%), piperacillin/tazobactam (47.2%), meropenem (41.7%), and levofloxacin (30.6%). Twenty out of thirty-six P. aeruginosa displayed multidrug resistance profiles and were classified as multidrug-resistant (MDR) (55.6%). Most of the bacterial isolates exhibited a high Multiple Antibiotic Resistance (MAR) Index ranging from 0.08 to 0.69 with a mean MAR index of 0.38. In the rPCR analysis of fifteen P. aeruginosa isolates, 14 isolates (93.3%) were detected harboring bla SHV, six isolates (40%) harbored bla TEM, and three isolates (20%) harbored bla CTX-M, being the least occurring ESBL. Results of the current study revealed that P. aeruginosa isolates recovered from nonclinical milieu are resistant to frontline clinically relevant antipseudomonal drugs. This is concerning as it poses a risk to the environment and constitutes a public health threat. Given the public health relevance, the paper recommends monitoring of multidrug-resistant pathogens in effluent environments.
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INTRODUCTION: Carbapenem-resistant Acinetobacter baumannii has been responsible for an increasing number of hospital-acquired infections globally. The study investigated the prevalence of carbapenemase-encoding genes in clinical multidrug-resistant A. baumannii strains. MATERIALS AND METHODS: A total of 100 nonduplicate multidrug-resistant A. baumannii strains were cultured from clinical samples obtained from healthcare facilities in the O. R. Tambo district. The strains were confirmed by detecting the intrinsic bla OXA-51-like gene. Antimicrobial susceptibility testing was performed by VITEK® 2 and autoSCAN-4 systems. The MIC of imipenem and meropenem was rechecked by E-test. Colistin MIC was confirmed by the broth microdilution method. Real-time PCR was performed to investigate the presence of carbapenemase-encoding genes. RESULTS: Most strains showed high resistance rates (>80%) to the antibiotics tested. Resistance to amikacin, tetracycline, and tigecycline were 50%, 64%, and 48%, respectively. All strains were fully susceptible to colistin. The bla OXA-51-like was detected in all strains whilst bla OXA-23-like, bla OXA-58-like, bla OXA-24-like, bla IMP-1, bla VIM, and bla NDM-1 were found in 70%, 8%, 5%, 4%, 3%, and 2% of strains, respectively. None of the tested strains harboured the genes bla SIM and bla AmpC. The coexistence of bla OXA-23-like, and bla IMP-1 or bla OXA-58-like was detected in 1% and 2% strains, respectively. A distinct feature of our findings was the coharbouring of the genes bla OXA-23-like, bla OXA-58-like, and bla IMP-1 in 2% strains, and this is the first report in the Eastern Cape Province, South Africa. The intI1 was carried in 80% of tested strains whilst ISAba1/bla OXA-51-like and ISAba1/bla OXA-23-like were detected in 15% and 40% of the strains, respectively. The detection of bla OXA-23-like, ISAba1/bla OXA-51-like, ISAba1/bla OXA-23-like, and bla OXA-23-like, bla OXA-58-like, and bla IMP-1 carbapenemases in strains had a significant effect on both imipenem and meropenem MICs. CONCLUSIONS: Results showed a high level of oxacillinases producing A. baumannii circulating in our study setting, highlighting the need for local molecular surveillance to inform appropriate management and prevention strategies.
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BACKGROUND: Acinetobacter baumannii is a challenging pathogen due to the rapid development of antimicrobial resistance and bioï¬lm formation. The objective of this study was to evaluate the effect of antimicrobial photodynamic inactivation against bioï¬lms of multidrug-resistant A. baumannii isolated from clinical, abattoir and aquatic sources. METHODS: The isolates were tested for susceptibility to imipenem, meropenem, tigecycline and colistin using autoSCAN-4 automated system and rechecked by the E-test. Methylene blue, Protoporphyrin IX, and a halogen lamp were used in the in vitro assay against biofilms of the isolates. The antimicrobial photodynamic inactivation was assessed by counting colony-forming units (CFU). RESULTS: The isolates from abattoir and aquatic sources were resistant to carbapenems (>64 µg/mL) but susceptible to tigecycline (2 µg/mL) and colistin (Abattoir, 0.35 µg/mL and Aquatic, 0.24 µg/mL), whereas the clinical isolate was susceptible to only colistin (0.5 µg/mL) using the E-test. The log survival percentages of the control group at a concentration of 20 µM were 5 × 10-6 % for Protoporphyrin IX and 2 × 10-6 % for Methylene blue. Therefore, Methylene blue showed higher bacterial reduction of 7.0 log10 colony forming units than 6.0 log10 for Protoporphyrin IX. No significant difference was observed with respect to the origin of isolates and the minimum inhibitory concentrations. CONCLUSION: The results indicate that antimicrobial photodynamic inactivation could be an alternative strategy for the control of infections caused by multi-drug resistant A. baumannii by significantly reducing bioï¬lm growth at a sub-lethal concentrations.
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Infecções por Acinetobacter , Acinetobacter baumannii , Fotoquimioterapia , Infecções por Acinetobacter/tratamento farmacológico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Biofilmes , Farmacorresistência Bacteriana Múltipla , Humanos , Azul de Metileno/farmacologia , Azul de Metileno/uso terapêutico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , ProtoporfirinasRESUMO
BACKGROUND: The process of harvesting honey is time consuming and labor intensive. A new system, the Flow Frame, has drastically simplified the harvesting process, enabling honey to be extracted directly from the hive with minimal processing. The sensory profile of honey is influenced, first, by botanical origin and subsequently by processing and storage parameters. A reduction in harvest processing may thus influence the sensory profile of honey harvested from FFs compared to that of honey produced from conventional processing. To test this hypothesis, two monofloral honeys (macadamia and yellow pea) were harvested from FFs, or by conventional honey extraction. Sensory profiling using conventional descriptive analysis was carried out for each floral source with an experienced trained panel. RESULTS: The two monofloral honeys harvested using the FF system had significantly (p < 0.05) higher floral and cleaner aftertaste sensory scores than the honey extracted using commercial (C) methods that involve the use of heat and centrifugation. CONCLUSION: The flow system retains honey's natural sensory properties compared to harvesting methods that require heat and centrifugation. © 2019 Society of Chemical Industry.
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Mel/análise , Lathyrus/química , Macadamia/química , Adulto , Idoso , Cor , Feminino , Análise de Alimentos , Qualidade dos Alimentos , Humanos , Masculino , Pessoa de Meia-Idade , Paladar , ViscosidadeRESUMO
ABSTRACT Introduction: The presence of Acinetobacter baumannii outside hospitals remains unclear. This study aimed to determine the prevalence of multidrug-resistance (MDR) A. baumannii in the extra-hospital environment in Mthatha, South Africa and to investigate the frequency of carbapenemase-encoding genes. Material and Methods: From August 2016 to July 2017 a total of 598 abattoir samples and 689 aquatic samples were collected and analyzed presumptively by cultural methods for the presence of A. baumannii using CHROMagar™ Acinetobacter medium. Species identification was performed by autoSCAN-4 (Dade Behring Inc., IL) and confirmed by the detection of their intrinsic blaOXA-51 gene. Confirmed MDR A. baumannii isolates were screened for the presence of carbapenemase-encoding genes, ISAba1 insertion sequence and integrase intI1. Results: In total, 248 (19.3%) Acinetobacter species were isolated. Acinetobacter. baumannii was detected in 183 (73.8%) of which 85 (46.4%) and 98 (53.6%) were recovered from abattoir and aquatic respectively. MDR A. baumannii was detected in 56.5% (48/85) abattoir isolates and 53.1% (52/98) aquatic isolates. Isolates showed high resistance to antimicrobials most frequently used to treat Acinetobacter infections such as piperacillin/tazobactam; abattoir (98% of isolates resistant), aquatic (94% of isolates resistant), ceftazidime (84%, 83%), ciprofloxacin (71%, 70%), amikacin (41%, 42%), imipenem (75%, 73%), and meropenem (74%, 71%). All the isolates were susceptible to tigecycline and colistin. All the isolates carried blaOXA-51-like. The blaOXA-23 was detected in 32 (66.7%) abattoir isolates and 11 (21.2%) aquatic isolates. The blaOXA-58-like was positive in 7 (14.6%) and 4 (7.7%) abattoir and aquatic isolates, respectively. Both groups of isolates lacked blaOXA-24-like, blaIMP-type, blaVIM-type, blaNDM-1, blaSIM, blaAmpC, ISAba1 and inI1. Isolates showed high level of Multiple Antibiotic Resistance Index (MARI) ranging from 0.20-0.52. Conclusion: Extra-hospital sources such as abattoir and aquatic environments may be a vehicle of spread of MDR A. baumannii strains in the community and hospital settings.
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Humanos , Infecções por Acinetobacter/microbiologia , Infecções por Acinetobacter/tratamento farmacológico , Farmacorresistência Bacteriana Múltipla/genética , Acinetobacter baumannii/isolamento & purificação , Antibacterianos/uso terapêutico , África do Sul/epidemiologia , Infecções por Acinetobacter/transmissão , Infecções por Acinetobacter/epidemiologia , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Prevalência , Estudos Transversais , Estudos Prospectivos , Acinetobacter baumannii/genéticaRESUMO
INTRODUCTION: The presence of Acinetobacter baumannii outside hospitals remains unclear. This study aimed to determine the prevalence of multidrug-resistance (MDR) A. baumannii in the extra-hospital environment in Mthatha, South Africa and to investigate the frequency of carbapenemase-encoding genes. MATERIAL AND METHODS: From August 2016 to July 2017 a total of 598 abattoir samples and 689 aquatic samples were collected and analyzed presumptively by cultural methods for the presence of A. baumannii using CHROMagar™ Acinetobacter medium. Species identiï¬cation was performed by autoSCAN-4 (Dade Behring Inc., IL) and confirmed by the detection of their intrinsic blaOXA-51 gene. Confirmed MDR A. baumannii isolates were screened for the presence of carbapenemase-encoding genes, ISAba1 insertion sequence and integrase intI1. RESULTS: In total, 248 (19.3%) Acinetobacter species were isolated. Acinetobacter. baumannii was detected in 183 (73.8%) of which 85 (46.4%) and 98 (53.6%) were recovered from abattoir and aquatic respectively. MDR A. baumannii was detected in 56.5% (48/85) abattoir isolates and 53.1% (52/98) aquatic isolates. Isolates showed high resistance to antimicrobials most frequently used to treat Acinetobacter infections such as piperacillin/tazobactam; abattoir (98% of isolates resistant), aquatic (94% of isolates resistant), ceftazidime (84%, 83%), ciprofloxacin (71%, 70%), amikacin (41%, 42%), imipenem (75%, 73%), and meropenem (74%, 71%). All the isolates were susceptible to tigecycline and colistin. All the isolates carried blaOXA-51-like. The blaOXA-23 was detected in 32 (66.7%) abattoir isolates and 11 (21.2%) aquatic isolates. The blaOXA-58-like was positive in 7 (14.6%) and 4 (7.7%) abattoir and aquatic isolates, respectively. Both groups of isolates lacked blaOXA-24-like, blaIMP-type, blaVIM-type, blaNDM-1,blaSIM, blaAmpC, ISAba1 and inI1. Isolates showed high level of Multiple Antibiotic Resistance Index (MARI) ranging from 0.20-0.52. CONCLUSION: Extra-hospital sources such as abattoir and aquatic environments may be a vehicle of spread of MDR A. baumannii strains in the community and hospital settings.
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Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/isolamento & purificação , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana Múltipla , Infecções por Acinetobacter/epidemiologia , Infecções por Acinetobacter/transmissão , Acinetobacter baumannii/genética , Estudos Transversais , Farmacorresistência Bacteriana Múltipla/genética , Humanos , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Prevalência , Estudos Prospectivos , África do Sul/epidemiologiaRESUMO
Despite the numerous health benefits of breastfeeding, few American women breastfeed for the optimal duration of time. Reasons given for not following national and global institutional breastfeeding recommendations are various and multi-faceted. However, for many American women who would like to breastfeed, unjust historical, social, economic, cultural, and environmental factors negatively impact their ability to breastfeed. Catholic social teaching seeks to protect the poor and the vulnerable by working for social and economic justice, encourages stewardship of the environment, and uplifts the family as the most important unit in society. As such, Catholic social teaching has clear implications for individuals and institutions seeking to make breastfeeding a more widespread, accepted practice. In response to the crisis in American rates of breastfeeding, American Catholic healthcare institutions should work to promote the just economic and social conditions necessary for American women to breastfeed their children, starting by implementing breastfeeding-friendly policies for patients and employees in their own institutions. SUMMARY: For many American women who would like to breastfeed, unjust historical, social, economic, cultural, and environmental factors negatively impact their ability to breastfeed. Catholic social teaching has clear implications for individuals and institutions seeking to make breastfeeding a more widespread, accepted practice. Therefore, American Catholic healthcare institutions should work particularly hard to promote the just economic and social conditions necessary for American women to breastfeed their children, starting by implementing breastfeeding-friendly policies for patients and employees in their own institutions.
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Soil in urban areas contains the residues of past land-uses and practices. Urban farming (keeping chickens, vegetable gardening) requires soil disturbance and can increase exposure of residents to these contaminants. We measured the level of lead, arsenic, cadmium, copper and zinc contaminants in soil and eggs from 26 backyard chicken coops across the Lower Hunter, NSW Australia. We compared the levels of metals in soil to Health Investigation Levels and metals in home-grown eggs to the levels in commercial eggs tested in this study or published by Food Standards Australia New Zealand. The levels of arsenic, cadmium, copper and zinc were low, both in soil and in home-grown eggs and were comparable to commercial eggs tested in this study. The Health Investigation Level for lead in soil (300mglead/kg soil) was exceeded at 7 of the 26 sites. The level of lead in home-grown eggs was generally higher than in commercial eggs. The reference health standard for meat (including chicken), fruit and vegetables of 0.1mglead/kg produce was exceeded in home-grown eggs from 7 of the 26 sites. There was a significant relationship between the lead level in eggs and the lead level in soil accessible to chickens. As soil lead increased, concentrations of lead in eggs tended to increase. No relationship was detected between the lead level in feed and in eggs. We recommend strategies to reduce ingestion of soil by chickens thereby reducing metal contamination in home-grown eggs.
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Criação de Animais Domésticos/métodos , Galinhas/metabolismo , Ovos/análise , Contaminação de Alimentos/análise , Metais/metabolismo , Óvulo/química , Poluentes do Solo/metabolismo , Animais , Abrigo para Animais , New South WalesRESUMO
We present evidence of the gravitational lensing of the cosmic microwave background by 10(13) solar mass dark matter halos. Lensing convergence maps from the Atacama Cosmology Telescope Polarimeter (ACTPol) are stacked at the positions of around 12 000 optically selected CMASS galaxies from the SDSS-III/BOSS survey. The mean lensing signal is consistent with simulated dark matter halo profiles and is favored over a null signal at 3.2σ significance. This result demonstrates the potential of microwave background lensing to probe the dark matter distribution in galaxy group and galaxy cluster halos.
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Oogenesis involves a sequence of cellular divisions and developmental changes leading to the formation of oocytes, whose role in development is to transfer genomic information to the next generation. During this process, the gene expression pattern changes considerably concomitant with genome remodeling, while genomic information is maintained. The development of the gonad in zebrafish is unique in that it goes through an initial ovarian phase and subsequently into either ovarian or testicular phases. How the germ cells choose to commit to an oogenic fate and enter meiosis or alternatively not to enter meiosis and commit to a spermatogenetic fate remains a key question in development. Lack of suitable markers has hampered the understanding of the principles controlling sex differentiation in zebrafish. The current study was aimed at finding substantive cytochemical markers to identify specific oocyte stages primarily focusing on the DNA and RNA component of cells, using fluorescent dyes: acridine orange and propidium iodide. The pattern of synthesis and appearance of nucleoli was stage specific and may be used to identify stages of oogenesis. A distinguishing and possibly diagnostic feature of the staining pattern observed was the low level of chromatin staining compared to other cellular structures. This may be related to the more diffuse state of chromatin that occurs prior to thickening of chromosomes from the pachytene stage onwards. Although the fluorescent dyes may be useful in determining the localization of nucleic acids in tissue sections, it was not possible to quantify the relative contribution of the DNA and RNA components of specific stages of oocyte growth.
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DNA/metabolismo , Microscopia Confocal/métodos , Oogênese , RNA/metabolismo , Laranja de Acridina/farmacologia , Animais , Linhagem da Célula , Feminino , Corantes Fluorescentes/farmacologia , Células Germinativas/citologia , Masculino , Microscopia de Fluorescência/métodos , Oócitos/citologia , Oogônios , Ovário/fisiologia , Propídio/farmacologia , Ribonucleases/metabolismo , Coloração e Rotulagem , Testículo/fisiologia , Peixe-ZebraRESUMO
Sucrose and monosaccharide transporters mediate long distance transport of sugar from source to sink organs and constitute key components for carbon partitioning at the whole plant level and in interactions with fungi. Even if numerous families of plant sugar transporters are defined; efflux capacities, subcellular localization and association to membrane rafts have only been recently reported. On the fungal side, the investigation of sugar transport mechanisms in mutualistic and pathogenic interactions is now emerging. Here, we review the essential role of sugar transporters for distribution of carbohydrates inside plant cells, as well as for plant-fungal interaction functioning. Altogether these data highlight the need for a better comprehension of the mechanisms underlying sugar exchanges between fungi and their host plants.
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Metabolismo dos Carboidratos , Proteínas de Transporte de Monossacarídeos/metabolismo , Micorrizas/metabolismo , Plantas/metabolismo , Sacarose/metabolismo , Microdomínios da Membrana/metabolismo , Monossacarídeos/metabolismo , Doenças das Plantas/microbiologia , Folhas de Planta/metabolismo , Plantas/microbiologia , SimbioseRESUMO
Progression through mitosis and meiosis during early zebrafish ovarian development is accompanied by highly regulated series of transformations in the architecture of oocytes. These cytoskeletal-dependent membrane events may be assumed to be brought about by deployment of proteins. While the cytoskeleton and its associated proteins play a pivotal role in each of these developmental transitions, it remains unclear how specific cytoskeletal proteins participate in regulating diverse processes of oocyte development in zebrafish. Results from this study show that a pool of spectrin accumulates during oogenesis and parallels an increase in volume of oocytes at pre-vitellogenic stages of development. Spectrin labeling is restricted to the surface of oogonia, the cortex of post-pachytene oocytes and later accumulates on the cytoplasm of pre-vitellogenic and vitellogenic oocytes. Results here suggest a correlation between spectrin labeling, increased cytoplasm volume of oocytes, an increase in the number of nucleoli and accumulation of cytoplasmic organelles. Overall, these results suggest that synthesis and storage of spectrin during pre-vitellogenic stages of oogenesis primes the egg with a pre-established pool of membrane-cytoskeletal precursors for use during embryogenesis, and that the presence of spectrin at the oocyte sub-cortex is essential for maintaining oocyte structure.
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Oócitos/metabolismo , Oogênese , Espectrina/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/fisiologia , Animais , Núcleo Celular/metabolismo , Feminino , Oócitos/citologia , Vitelogênese , Peixe-Zebra/metabolismoRESUMO
Symbiosis is well recognized as a major force in plant ecology and evolution. However, there is considerable uncertainty about the functional, ecological and evolutionary benefits of the very widespread facultative arbuscular mycorrhizal (AM) associations, in which the plants can grow and reproduce whether or not they are colonized by AM fungi. Here we address the significance of new research findings that are overturning conventional views that facultative AM associations can be likened to parasitic fungus-plant associations. Specifically, we address the occurrence and importance of phosphate uptake via AM fungi that does not result in increases in total phosphorus (P) uptake or in plant growth, and possible signalling between AM fungi and plants that can result in plant growth depressions even when fungal colonization remains very low. We conclude that, depending on the individual AM fungi that are present, the role of facultative AM associations in the field, especially in relation to plant competition, may be much more subtle than has been previously envisaged.
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Fungos/fisiologia , Micorrizas/fisiologia , Fósforo/fisiologia , Desenvolvimento Vegetal , Simbiose/fisiologia , Plantas/microbiologia , Transdução de Sinais/fisiologiaRESUMO
A new antibiotic polyene tetramic acid, ravenic acid (2), has been isolated from the mycelia of a cultured fungus, Penicillium sp. The structure of ravenic acid was determined by detailed spectroscopic analysis and the major isomer identified as possessing (3Z, 7E, 9E, 11E, 13E) stereochemistry.