Impact of Transgenic Wheat with wheat yellow mosaic virus Resistance on Microbial Community Diversity and Enzyme Activity in Rhizosphere Soil.

by Wu, Jirong, Yu, Mingzheng, Xu, Jianhong, Du, Juan, Ji, Fang, Dong, Fei, Li, Xinhai, Shi, Jianrong [2014-06-01]

Academic Journal

pages 11

The transgenic wheat line N12-1 containing the WYMV-Nib8 gene was obtained previously through particle bombardment, and it can effectively control the wheat yellow mosaic virus (WYMV) disease transmitted by Polymyxa graminis at turngreen stage. Due to insertion of an exogenous gene, the transcriptome of wheat may be altered and affect root exudates. Thus, it is important to investigate the potential environmental risk of transgenic wheat before commercial release because of potential undesirable ecological side effects. Our 2-year study at two different experimental locations was performed to analyze the impact of transgenic wheat N12-1 on bacterial and fungal community diversity in rhizosphere soil using polymerase chain reaction-denaturing gel gradient electrophoresis (PCR-DGGE) at four growth stages (seeding stage, turngreen stage, grain-filling stage, and maturing stage). We also explored the activities of urease, sucrase and dehydrogenase in rhizosphere soil. The results showed that there was little difference in bacterial and fungal community diversity in rhizosphere soil between N12-1 and its recipient Y158 by comparing Shannon's, Simpson's diversity index and evenness (except at one or two growth stages). Regarding enzyme activity, only one significant difference was found during the maturing stage at Xinxiang in 2011 for dehydrogenase. Significant growth stage variation was observed during 2 years at two experimental locations for both soil microbial community diversity and enzyme activity. Analysis of bands from the gel for fungal community diversity showed that the majority of fungi were uncultured. The results of this study suggested that virus-resistant transgenic wheat had no adverse impact on microbial community diversity and enzyme activity in rhizosphere soil during 2 continuous years at two different experimental locations. This study provides a theoretical basis for environmental impact monitoring of transgenic wheat when the introduced gene is derived from a virus. [ABSTRACT FROM AUTHOR]


Structural and Functional Characterization of the Bacterial Type III Secretion Export Apparatus.

by Dietsche, Tobias, Tesfazgi Mebrhatu, Mehari, Zilkenat, Susann, Grin, Iwan, Wagner, Samuel, Brunner, Matthias J., Marlovits, Thomas C., Abrusci, Patrizia, Lea, Susan, Yan, Jun, Robinson, Carol V., Franz-Wachtel, Mirita, Macek, Boris, Schärfe, Charlotta, Kohlbacher, Oliver, Galán, Jorge E. [2016-12-15]

Academic Journal

pages 25

Bacterial type III protein secretion systems inject effector proteins into eukaryotic host cells in order to promote survival and colonization of Gram-negative pathogens and symbionts. Secretion across the bacterial cell envelope and injection into host cells is facilitated by a so-called injectisome. Its small hydrophobic export apparatus components SpaP and SpaR were shown to nucleate assembly of the needle complex and to form the central “cup” substructure of a Salmonella Typhimurium secretion system. However, the in vivo placement of these components in the needle complex and their function during the secretion process remained poorly defined. Here we present evidence that a SpaP pentamer forms a 15 Å wide pore and provide a detailed map of SpaP interactions with the export apparatus components SpaQ, SpaR, and SpaS. We further refine the current view of export apparatus assembly, consolidate transmembrane topology models for SpaP and SpaR, and present intimate interactions of the periplasmic domains of SpaP and SpaR with the inner rod protein PrgJ, indicating how export apparatus and needle filament are connected to create a continuous conduit for substrate translocation. [ABSTRACT FROM AUTHOR]


Introduction and geographic availability of new antibiotics approved between 1999 and 2014.

by Kållberg, Cecilia, Årdal, Christine, Salvesen Blix, Hege, Klein, Eili, M. Martinez, Elena, Lindbæk, Morten, Outterson, Kevin, Røttingen, John-Arne, Laxminarayan, Ramanan [2018-10-16]

Academic Journal

pages 19

Background: Despite the urgent need for new, effective antibiotics, few antibiotics of value have entered the market during the past decades. Therefore, incentives have been developed to stimulate antibiotic R&D. For these incentives to be effective, geographic availability for recently approved antibiotics needs to be better understood. In this study, we analyze geographic availability and market introduction of antibiotics approved between 1999 and 2014. Material and method: We identified antibiotics, considered new chemical entities (NCEs) for systemic use approved globally between 1999 and 2014, from national medicine agencies’ lists of approved drugs, and data from the WHO Collaborating Center for Drug Statistics. Geographic availability was mapped using sales data from IQVIA, and analyzed with regards to class, indication, safety, and origin. Results: Of the 25 identified NCEs, only 12 had registered sales in more than 10 countries. NCEs with the widest geographic availability had registered sales in more than 70 countries within a ten-year timeframe and 30 countries within a three-year timeframe, spreading across five different geographic regions and three country income classes. Half (52%) of the NCEs had an indication for infections caused by antibiotic- resistant bacteria, little diversity was seen regarding target pathogen and indication. Antibiotics originated from and/or marketed by companies from the US or Europe had greater geographic availability compared to Japanese antibiotics, which seldom reached outside of Asia. For 20 NCEs developers chose to fully or partially sublicense marketing rights to a number of companies of different sizes. Conclusion: Our findings show great variation in geographic availability of antibiotics, indicating that availability in multiple regions and country income classes is possible, but rarely seen within a few years of market authorization. Sublicensing agreements between multiple companies was common practice. Moreover, differences were seen between countries regarding benefit/risk evaluations and company behavior. These findings could be a potential source of uncertainties, and create barriers to assure that working antibiotics are developed and made available according to public health needs. [ABSTRACT FROM AUTHOR]


Current status of MALDI-TOF mass spectrometry in clinical microbiology.

by Tsung-Yun Hou, Chuan Chiang-Ni, Shih-Hua Teng [2019-01-01]

Academic Journal

pages 11

Mass spectrometry (MS) is a type of analysis used to determine what molecules make up a sample, based on the mass spectrum that are created by the ions. Mass spectrometers are able to perform traditional target analyte identification and quantitation; however, they may also be used within a clinical setting for the rapid identification of bacteria. The causative agent in sepsis is changed over time, and clinical decisions affecting the management of infections are often based on the outcomes of bacterial identification. Therefore, it is essential that such identifications are performed quickly and interpreted correctly. Matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometer is one of the most popular MS instruments used in biology, due to its rapid and precise identification of genus and species of an extensive range of Gram-negative and -positive bacteria. Microorganism identification by Mass spectrometry is based on identifying a characteristic spectrum of each species and then matched with a large database within the instrument. The present review gives a contemporary perspective on the challenges and opportunities for bacterial identification as well as a written report of how technological innovation has advanced MS. Future clinical applications will also be addressed, particularly the use of MALDI-TOF MS in the field of microbiology for the identification and the analysis of antibiotic resistance. [ABSTRACT FROM AUTHOR]


Academic Journal

pages 6

We introduce a generic, simple, and inexpensive method for performing microbiological, enzymatic, or inorganic catalysis with solids using standard histology and microbiology laboratory equipment. Histology cassettes were used to standardize hydrodynamic conditions and to protect the catalysts and their solid supports. Histology cassettes have the following advantages: they are readily available, inexpensive, solvent and acid resistant, automatable, and the slots in the cassette walls allow liquid to circulate freely. Standard Erlenmeyer flasks were used as reaction vessels. We developed a new camera to observe the movement and position of the histology cassettes as well as the liquid in the Erlenmeyer flasks. The camera produces a stable image of the rotating liquid in the Erlenmeyer flask. This visualization method revealed that in a 250 ml Erlenmeyer flask, stable operating conditions are achieved at a shaking frequency of 300 rpm and a fill volume of 30 ml. In vessels with vertical walls, such as beakers or laboratory bottles, the movement of the histology cassette is not reproducible. Mass transfer characterization using a biological model system and the chemical sulfite-oxidation method revealed that the histology cassette does not influence gas-liquid mass transfer. [ABSTRACT FROM AUTHOR]


Academic Journal

pages 10

Burkholderia pseudomallei is the causative agent of melioidosis, which is an endemic disease in Northeast Thailand and Northern Australia. Environmental reservoirs, including wet soils and muddy water, serve as the major sources for contributing bacterial infection to both humans and animals. The whole-cell matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (whole-cell MALDI-TOF MS) has recently been applied as a rapid, accurate, and high-throughput tool for clinical diagnosis and microbiological research. In this present study, we employed a whole-cell MALDI-TOF MS approach for assessing its potency in clustering a total of 11 different B. pseudomallei isolates (consisting of 5 environmental and 6 clinical isolates) with respect to their origins and to further investigate the source-identifying biomarker ions belonging to each bacterial group. The cluster analysis demonstrated that six out of eleven isolates were grouped correctly to their sources. Our results revealed a total of ten source-identifying biomarker ions, which exhibited statistically significant differences in peak intensity between average environmental and clinical mass spectra using ClinProTools software. Six out of ten mass ions were assigned as environmental-identifying biomarker ions (EIBIs), including, m/z 4,056, 4,214, 5,814, 7,545, 7,895, and 8,112, whereas the remaining four mass ions were defined as clinical-identifying biomarker ions (CIBIs) consisting of m/z 3,658, 6,322, 7,035, and 7,984. Hence, our findings represented, for the first time, the source-specific biomarkers of environmental and clinical B. pseudomallei. [ABSTRACT FROM AUTHOR]


Progress in the science of probiotics: from cellular microbiology and applied immunology to clinical nutrition.

by Walker, W. Allan, Goulet, Olivier, Morelli, Lorenzo, Antoine, Jean-Michel [2006-07-02]

Academic Journal

pages 18

Probiotic research is progressing rapidly with strong scientific-based observations. New molecular biologic techniques for the more accurate identification of intestinal microflora and seminal studies that have helped define the function of commensal bacteria in the gut have been reported recently. In functional terms, new techniques are operational to study the affect of microbial–host “crosstalk” between both bacteria and the host. Probiotics have been shown to initiate the activation of specific genes localized to these cells. Both the bacterial and host aspects of microbiota–host crosstalk can now be studied, in particular thanks to simplified in vivo gnotobiotic mouse models. Their functional genomic studies enable the screening for probiotic potential and for investigating the modulated expression of genes involved in a broad range of intestinal functions including regulation of nutrient uptake and metabolism, mucosal barrier and epithelial cell function, xenobiotic metabolism, and strengthening of the innate immune system. An important function of probiotics is its effect on the gut immune system. The latter may work by enhancing mucosal barrier function, preventing apoptosis of epithelial cells and ultimately, decreasing antigen uptake, especially in the small bowel. Clinically, there is strong evidence that some probiotics improve the digestibility of lactose and others prevent the recurrence of pouchitis after inflammatory bowel disease (IBD) surgery. There is reasonably strong evidence for the efficacy of probiotics in childhood infectious gastroenteritis and antibiotic-associated diarrhea. Recent data suggest the potential efficacy of probiotic strains in atopic eczema, IBD, Helicobacter pylori gastritis, neonatal necrotizing enterocolitis and as a substitute for inadequate initial neonatal colonization. [ABSTRACT FROM AUTHOR]


Organization and function of anionic phospholipids in bacteria.

by Lin, Ti-Yu, Weibel, Douglas [2016-05-15]

Academic Journal

pages 13

In addition to playing a central role as a permeability barrier for controlling the diffusion of molecules and ions in and out of bacterial cells, phospholipid (PL) membranes regulate the spatial and temporal position and function of membrane proteins that play an essential role in a variety of cellular functions. Based on the very large number of membrane-associated proteins encoded in genomes, an understanding of the role of PLs may be central to understanding bacterial cell biology. This area of microbiology has received considerable attention over the past two decades, and the local enrichment of anionic PLs has emerged as a candidate mechanism for biomolecular organization in bacterial cells. In this review, we summarize the current understanding of anionic PLs in bacteria, including their biosynthesis, subcellular localization, and physiological relevance, discuss evidence and mechanisms for enriching anionic PLs in membranes, and conclude with an assessment of future directions for this area of bacterial biochemistry, biophysics, and cell biology. [ABSTRACT FROM AUTHOR]


Microbiological safety of pastille products new compounding.

by Zhivotovska, Arina, Gregirchak, Natalia [2013-10-01]

Academic Journal

pages 7

Introduction. Due to the increasing number of people with diabetes and gastro-intestinal diseases appeared a need to develop new recipes of sweets with sweeteners. For identify of influence of lactulose and fructose on microbiological sweet's parameters of new formulations was analyzed their microbiological safety on case of souffle. Materials and methods. The analysis were carried out by regulatory microbiological parameters. Also, was checked number of disputes-making bacterias ( DMB ). With the goal to create conditions of provocative testing, samples of souffle except of regulated temperature, kept at the temperature of 10 ° C above regulated. Results. Marked difference of all samples to established standards. Investigated the dynamics of changes in total contamination of submitted samples of souffle during storage and the effect of sugars on the microbiological safety of the new candy recipes. Found that fruktoz-contained souffle with somewhat lower microbiological parameters than products of sucrose, which is a component of traditional sweets. Adding of lactulose to recipe of soufflé does not affect their microbiological stability. Raising the temperature to 10° C from the measured norm did not significantly affect the performance of all microbiological samples for regulated product shelf life. [ABSTRACT FROM AUTHOR]


VENTILATOR-ASSOCIATED PNEUMONIA; MICROBIOLOGY, MULTIDRUG RESISTANCE IMPACT AND ASSOCIATED RISK FACTORS IN TERTIARY HOSPITALS SETTINGS.

by Zubair, Saba, Ali, Huma, Zafar, Farya, Raza, Syed Faheem, Ashraf, Irfan, Warind, Javaid, Ejaz Beg, Anwer, Rizvi, Mehwish, Zaib-un-Nisa, Naqvi, Ghazala R., Tariq, Anum [2018-09-01]

Academic Journal

pages 8

Background: Patients associated with VAP having mortality rates range from 20 to 50% and this may extend up to 70% when multi-resistant and invasive pathogens accountable for infection, however, VAP is also interrelated with noteworthy rate of morbidity, extended period of stay in ICU, protracted MV, and augmented hospitalization cost. Objectives: To review the risk factors, incidence and transience rate of mortality for ventilator-associated pneumonia. Design: Prospective and cross sectional way. Period: From April 2016 to December 2016. Setting: Different Tertiary Care Institutes of Karachi, Pakistan. Method: A structured data collection form was prepared to record the information and validated using spearman correlation coefficient and Cronbach's α value. Value of α = 0.902 and p = 0.913 have revealed the suitable degree of reliability and uniformity. Data was collected with respect to gender, age, antibiotic utilization record, and main diagnosis outcomes. Microbiological basis of ventilator-associated pneumonia was assessed using patient lab record for rate and seclusion of organism. Results: In this study a detail of significant virulence factor articulated by these microorganisms has been depicted. Statistically insignificant differences were observed among the groups with respect to clinical and demographic characteristics like mean age, gender, infection severity scores (SOFA, MODS, CPIS and APACHE II), immune status of patients and type of the cases including surgical or clinical scenario. 39.3% patients developed early onset while 60.6% of cohort was observed with late onset of VAP. Conclusion: The precise microbial source of VAP are numerous and diverse. The realistic challenge at the present time is to portray the authentic approximate of the clinical consequences associated with VAP. Henceforth such investigations may be supportive in origination of the most favorable institutional antimicrobial strategy to reduce the associated complications of this threat. [ABSTRACT FROM AUTHOR]


Academic Journal

pages 8

Purpose: The purpose of this study was to explore nursing students’ experience in microbiology courses. Methods: Data were gathered through 4 focus group interviews and 1 in-depth personal interview, by 19 nursing students who attended microbiology courses. Data were collected June 15-July 20, 2018. Conventional content analysis was used for data analysis. Results: The result of this study revealed 4 categories: “facing the challenge”, “types of learning”, “lack of learning motivation”, “acquiring knowledge of infection”. Conclusion: Findings suggest that it is important to identify nursing students’ perspectives, to improve microbiology curriculum in the educational process. Also, it is necessary to connect continuously, between educational and practical environments, for effective management of microbiology courses. [ABSTRACT FROM AUTHOR]


Academic Journal

pages 4

The purpose of this study was to investigate whether radiology equipment could be a reservoir for microorganisms which aid the spread of infection to patients. Swab samples were collected from selected X-ray equipment and accessories and sent to the microbiology laboratory for culturing and identification using standard laboratory procedure. Bacteria were isolated in 38 swabs representing 42% of all the swab samples. Staphylococcus aureus, lactose fermenting coliforms, staphylococcus saprophyticus, pseudomonas aeruginosa and coagulase-negative staphylococcus were the bacteria isolated from the swab samples. Lactose fermenting coliforms were isolated the most , namely 17 times (45%); pseudomonas aeruginosa were only isolated once. X-ray cassettes recorded the highest number of times that bacteria were isolated (55%) with coliform being isolated most often (52%). The research concluded that the cleaning criterion that was being employed was inadequate resulting in the presence of microorganisms on imaging equipment and accessories. The study therefore recommended that the radiology staff should adhere more to infection control policies to curb the growth of microorganisms. [ABSTRACT FROM AUTHOR]


Disentangling factors that shape the gut microbiota in German Shepherd dogs.

by Vilson, Åsa, Ramadan, Ziad, Li, Qinghong, Hedhammar, Åke, Reynolds, Arleigh, Spears, Julie, Labuda, Jeff, Pelker, Robyn, Björkstén, Bengt, Dicksved, Johan, Hansson-Hamlin, Helene [2018-03-23]

Academic Journal

pages 16

The aim of this study was to explore the development of the gut microbiota in 168 German Shepherd dogs (30 litters) from 7 weeks to 18 months of age and furthermore, to study the effect of relatedness, maternal microbiota composition and living environment in a large and well-defined population of dogs. Using 454 pyrosequencing, we assessed the effects of pre- and postnatal probiotic supplementation (Lactobacillus johnsonii NCC533 (La1)) and analysed whether administration of the probiotic strain influenced fecal microbiota composition in a placebo controlled double-blinded study. The bitches were treated with probiotics or placebo during last trimester of pregnancy and until their puppies were 8 weeks old, the puppies received the same treatment as their mothers between 3–12 weeks of age. Samples from bitches were collected at pregnancy day 42, partum, 4 weeks postpartum and 7 weeks postpartum and from puppies at the age 4 weeks, 7 weeks, 12–13 months and 15–18 months. Serum IgA, total serum IgE, fecal IgA and IgG antibody responses against canine distemper virus were analysed by ELISA in order to detect any immune stimulating effects of the probiotic strain. Analysis of the fecal microbiota composition showed that the predominant phyla were the same in 7 weeks old puppies as in pregnant and lactating bitches (Firmicutes, Fusobacteria, Bacteroidetes). Proportions among different bacteria as well as diversity varied from 7 weeks old puppies up to 15–18 months of age. Litter mates had a more similar fecal microbiota compared to unrelated dogs and 7 weeks old puppies were more similar to their mothers than to unrelated bitches at 7 weeks postpartum but not at partum. We observed a change in the relative abundance of different bacteria during lactation, and an increase in diversity from pregnancy to end of lactation. The microbial diversity was affected by living area where dogs living in big cities had higher diversity compared to dogs living at the countryside. However, we were not able to demonstrate an effect by pre and postnatal exposure to Lactobacillus johnsonii NCC533 (La1) upon the diversity or composition of the microbiota or the levels of serum IgA, total serum IgE, fecal IgA or vaccine response. Our findings provide a better understanding of the canine fecal microbiota in growing dogs as well as in pregnant and lactating bitches. This information forms a basis for further research on the connection between early gut colonization and immune function later in life. [ABSTRACT FROM AUTHOR]


Nitrate addition has minimal short-term impacts on greenland ice sheet supraglacial prokaryotes.

by Cameron, Karen A., Stibal, Marek, Chrismas, Nathan, Box, Jason, Jacobsen, Carsten S. [2017-04-01]

Academic Journal

pages 7

Tropospheric nitrate levels are predicted to increase throughout the 21st century, with potential effects on terrestrial ecosystems, including the Greenland ice sheet (GrIS). This study considers the impacts of elevated nitrate concentrations on the abundance and composition of dominant bulk and active prokaryotic communities sampled from in situ nitrate fertilization plots on the GrIS surface. Nitrate concentrations were successfully elevated within sediment-filled meltwater pools, known as cryoconite holes; however, nitrate additions applied to surface ice did not persist. Estimated bulk and active cryoconite community cell abundance was unaltered by nitrate additions when compared to control holes using a quantitative PCR approach, and nitrate was found to have a minimal affect on the dominant 16S rRNA gene-based community composition. Together, these results indicate that sampled cryoconite communities were not nitrate limited at the time of sampling. Instead, temporal changes in biomass and community composition were more pronounced. As these in situ incubations were short (6 weeks), and the community composition across GrIS surface ice is highly variable, we suggest that further efforts should be considered to investigate the potential long-term impacts of increased nitrate across the GrIS. [ABSTRACT FROM AUTHOR]


Emergence of vancomycin-resistant enterococci in South Africa: Implications for public health.

by Foka, Frank E. Tatsing, Kumar, Ajay, Ateba, Collins N. [2018-09-01]

Academic Journal

pages 7

The article focuses on the threat to public health in South Africa caused due to the vancomycin-resistant enterococci (VREs), which creates various health problems by transmitting their resistance genes to susceptible pathogens. It discusses the prevalence of VRE in in water, food items, farming and agriculture. It mentions the current management of antimicrobial resistance with some recommendations on how to tackle the issue of vancomycin resistance genes in South Africa .


Oak killer leaves scientists foxed.

No author [2008-09-04]

Periodical

pages unknown

The article reports on the investigation by British scientists on a mysterious killer disease attacking oaks. Forestry Commission scientists asserted that the infection leads to massive stem bleeding and acute oak decline. Scientists need to conduct further studies that will take months or years to identify particular species of the bacteria found in the infected oaks.


Pyrosequencing enumerates and contrasts soil microbial diversity.

by Roesch, Luiz F. W., Fulthorpe, Roberta R., Riva, Alberto, Casella, George, Hadwin, Alison K. M., Kent, Angela D., Daroub, Samira H., Camargo, Flavio A. O., Farmerie, William G., Triplett, Eric W. [2007-08-01]

Academic Journal

pages 8

Estimates of the number of species of bacteria per gram of soil vary between 2000 and 8.3 million (Gans et al., 2005; Schloss and Handelsman, 2006). The highest estimate suggests that the number may be so large as to be impractical to test by amplification and sequencing of the highly conserved 16S rRNA gene from soil DNA (Gans et al., 2005). Here we present the use of high throughput DNA pyrosequencing and statistical inference to assess bacterial diversity in four soils across a large transect of the western hemisphere. The number of bacterial 16S rRNA sequences obtained from each site varied from 26 140 to 53 533. The most abundant bacterial groups in all four soils were the Bacteroidetes, Betaproteobacteria and Alphaproteobacteria. Using three estimators of diversity, the maximum number of unique sequences (operational taxonomic units roughly corresponding to the species level) never exceeded 52 000 in these soils at the lowest level of dissimilarity. Furthermore, the bacterial diversity of the forest soil was phylum rich compared to the agricultural soils, which are species rich but phylum poor. The forest site also showed far less diversity of the Archaea with only 0.009% of all sequences from that site being from this group as opposed to 4%–12% of the sequences from the three agricultural sites. This work is the most comprehensive examination to date of bacterial diversity in soil and suggests that agricultural management of soil may significantly influence the diversity of bacteria and archaea.The ISME Journal (2007) 1, 283–290; doi:10.1038/ismej.2007.53; published online 5 July 2007 [ABSTRACT FROM AUTHOR]

RNA

Academic Journal

pages 10

Nucleic acid separation is an increasingly important tool for molecular biology. Before modern technologies could be used, nucleic acid separation had been a time- and work-consuming process based on several extraction and centrifugation steps, often limited by small yields and low purities of the separation products, and not suited for automation and up-scaling. During the last few years, specifically functionalised magnetic particles were developed. Together with an appropriate buffer system, they allow for the quick and efficient purification directly after their extraction from crude cell extracts. Centrifugation steps were avoided. In addition, the new approach provided for an easy automation of the entire process and the isolation of nucleic acids from larger sample volumes. This review describes traditional methods and methods based on magnetic particles for nucleic acid purification. The synthesis of a variety of magnetic particles is presented in more detail. Various suppliers of magnetic particles for nucleic acid separation as well as suppliers offering particle-based kits for a variety of different sample materials are listed. Furthermore, commercially available manual magnetic separators and automated systems for magnetic particle handling and liquid handling are mentioned. [ABSTRACT FROM AUTHOR]


Arrays and Medical Microbiology.

by Versalovic, James [2009-04-01]

Academic Journal

pages 5

The article focuses on medical microbiology. It discusses the importance of integrating molecular data to direct change in medicine and presents the limitations of strategies in diagnostic microbiology. It also cites the significance of array-based testing in molecular diagnostics for pathologists along with the application of global molecular diagnostic strategies in oncology, pharmacogenomics, and other areas.


Academic Journal

pages 4

Discusses the celebration of the 40th anniversary of the "Journal of Applied Biochemistry and Microbiology." Journal's reflection of the potential of scientific results in the fields of microbiology, biochemistry and biotechnology for practical application; Authors published in the journal; Journal's elucidation of works on the biochemical fundamentals of plant immunity; Articles awarded with various prizes.


Electroendocytosis Is Driven by the Binding of Electrochemically Produced Protons to the Cell's Surface.

by Ben-Dov, Nadav, Rozman Grinberg, Inna, Korenstein, Rafi [2012-11-01]

Academic Journal

pages 8

Electroendocytosis involves the exposure of cells to pulsed low electric field and is emerging as a complementary method to electroporation for the incorporation of macromolecules into cells. The present study explores the underlying mechanism of electroendocytosis and its dependence on electrochemical byproducts formed at the electrode interface. Cell suspensions were exposed to pulsed low electric field in a partitioned device where cells are spatially restricted relative to the electrodes. The cellular uptake of dextran-FITC was analyzed by flow cytometery and visualized by confocal microscopy. We first show that uptake occurs only in cells adjacent to the anode. The enhanced uptake near the anode is found to depend on electric current density rather than on electric field strength, in the range of 5 to 65 V/cm. Electrochemically produced oxidative species that impose intracellular oxidative stress, do not play any role in the stimulated uptake. An inverse dependence is found between electrically induced uptake and the solution's buffer capacity. Electroendocytosis can be mimicked by chemically acidifying the extracellular solution which promotes the enhanced uptake of dextran polymers and the uptake of plasmid DNA. Electrochemical production of protons at the anode interface is responsible for inducing uptake of macromolecules into cells exposed to a pulsed low electric field. Expanding the understanding of the mechanism involved in electric fields induced drug-delivery into cells, is expected to contribute to clinical therapy applications in the future. [ABSTRACT FROM AUTHOR]


Academic Journal

pages 17

The goal of modern taxonomy is to understand the relationships of living organisms in terms of evolutionary descent. Thereby, the relationships between living organisms are understood in terms of nested clades-every time a speciation event takes place, two new clades are produced. Life comprises three domains of living organisms, these are the Bacteria, the Archaea and the Eukaryota. Within the eukaryotic domain, the fungi form a monophyletic group of the eukaryotic crown group and are thus high up in the evolutionary hierarchy of life. Fungus-like organisms possess certain morphological features of fungi, such as the hyphal organization of the Oomycota or the spores and reproductive structures inside a fructification of plasmodiophorids (Plasmodiophoromycota) and slime moulds (Mycetozoa). The first group are algae which secondarily lost their plastids during evolution and contain cellulose in their cell walls. Both osmotrophic phyla, the Oomycota and the Plasmidiophoromycota belong to the Chromista and Rhizaria, respectively, whereas the last group, the cellular and plasmodial slime moulds (Mycetozoa) are phagotrophic amoeboid protists belonging to the Amoebozoa. These fungus-like organisms are not considered further in this review. The Fungi sensu stricto comprise a heterogenous, often inconspicuous group of microorganisms which (1) are primarily heterotrophic with an (2) osmotrophic style of nutrition containing (3) chitin and its derivatives in the cell wall. This review discusses species concepts and current strategies in fungal taxonomy, phylogenetic affiliations of miscellaneous fungus-like groups like the microsporidia, perspectives of fungal nomenclature, and their impact on natural product research. [ABSTRACT FROM AUTHOR]