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Highlights: [•] Antibiotics damage the intestinal microbiota and disrupt colonization resistance predisposing us to recurrent C. difficile infection (CDI). [•] Faecal microbiota transplantation (FMT) is a promising treatment for recurrent C. difficile infection. [•] Mixtures of beneficial bacteria known as bacteriotherapy should be developed for treatment of CDI and other diseases linked to dysbiosis in the intestinal microbiota. [Copyright &y& Elsevier]

Abstract: Current conventional treatments for cancer lack tumour selectivity resulting in the destruction of healthy tissue and severe adverse effects to the patient in addition to limiting the administration dose and efficacy. Hence, it is imperative that we seek alternative approaches to treat cancer that localise therapeutic agents to the site of the tumour and spare normal tissue. The use of bacteria in cancer therapy represents one such approach. Bacteria were first used as anti-cancer agents over a century ago. Today, this field has re-emerged from the past and is progressing at a rapid rate. Bacteria are used as anticancer agents either alone or in combination with conventional treatments and have been armed with an arsenal of therapeutic genes, which enhance their efficacy. Bacterial directed enzyme prodrug therapy (BDEPT) is one of the most promising approaches, which harnesses the tumour-specific location of bacteria to locally activate systemically administered ‘prodrugs’ within the tumour in order to induce selective tumour destruction. BDEPT is a relatively new concept. It was originally conceived more than 10years ago but it is only until recently that we witness a surge in activity in this field. In this review, we provide a full account of developments in the field of BDEPT since its inception. We share technical knowhow and discuss optimization strategies for vector and enzyme combinations, provide a clear view of the research landscape and suggest possible directions for the field. [Copyright &y& Elsevier]

Attention has been drawn to phage therapy as an alternative approach for controlling pathogenic bacteria such as Flavobacterium psychrophilum in salmonid aquaculture, which can give rise to high mortalities, especially in rainbow trout fry. Recently, phages have been isolated with a broad host range and a strong lytic potential against pathogenic F. psychrophilum under experimental conditions. However, little is known about the fate of phages at environmental conditions. Here, we quantified the dispersal and fate of F. psychrophilum phages and hosts in rainbow trout fry after intraperitoneal injection. Both phages and bacteria were isolated from the fish organs for up to 10 days after injection, and coinjection with both bacteria and phages resulted in a longer persistence of the phage in the fish organs, than when the fish had been injected with the phages only. The occurrence of both phage and bacterium was most prevalent in the kidney and spleen, with only minor occurrence in the brain. The experiment showed that injected phages were rapidly spread in the internal organs of the fish, also in the absence of bacteria. Parallel examination of the regulation of bacteriophage infectivity in controlled laboratory experiments at various environmental conditions showed that pH had only minor effects on long-term (3 months) phage infectivity within a pH range of 4.5 to 7.5, whereas phage infectivity was immediately lost at pH 3. In the absence of host cells, phage infectivity decreased by a factor of 10,000 over 55 days in untreated pond water, while the sterilization and removal of particles caused a 100-fold increase in phage survival relative to the control. In addition, F. psychrophilum-sped&c phages maintained their infectivity for ∼2 months in glycerol at -80°C, whereas infectivity decreased by a factor 10 when kept in a buffer at 20°C. Only a very small degradation in infectivity was seen when bacteriophages were added and dried on fish feed pellets. Together, these results indicate that application of bacteriophages represents a promising approach for the control of P. psychrophilum infections in trout and suggest fish feed as a potential delivery method. [ABSTRACT FROM AUTHOR]

Cancer is a leading cause of death in the world. The rapid development of medicine and pharmacology allows to create new and effective anticancer drugs. Among modern anticancer drugs are bacterial proteins. Until now has been shown anticancer activity among others azurin and exotoxin A from Pseudomonas aeruginosa, Pep27anal2 from Streptococcus pneumoniae, diphtheria toxin from Corynebacterium diphtheriae, and recently discovered Entap from Enterococcus sp. The study presents the current data regarding the properties, action and anticancer activity of listed peptides. [ABSTRACT FROM AUTHOR]

Assessing the distribution of 16S rRNA gene sequences within a biological sample represents the current state-of-the-art for determination of human gut microbiota composition. Advances in dissecting the microbial biodiversity of this ecosystem have very much been dependent on the development of novel high-throughput DNA sequencing technologies, like the Ion Torrent. However, the precise representation of this bacterial community may be affected by the protocols used for DNA extraction as well as by the PCR primers employed in the amplification reaction. Here, we describe an optimized protocol for 16S rRNA gene-based profiling of the fecal microbiota. [ABSTRACT FROM AUTHOR]

The use of live bacteria in cancer therapies offers exciting possibilities. Nowadays, an increasing number of genetically engineered bacteria are emerging in the field, with applications both in therapy and diagnosis. In parallel, purified bacterial products are also gaining relevance as new classes of bioactive products to treat and prevent cancer growth and metastasis. In the first part of the article, we review the latest findings regarding the use of live bacteria and products as anti-cancer agents, paying special attention to immunotoxins, proteins, and peptides. In particular, we focus on the recent results of using azurin or its derived peptide as anticancer therapeutic agents. In the second part, we discuss the challenges of using metagenomic techniques as a distinctive approach for discovering new anti-cancer agents from bacterial origin. [ABSTRACT FROM AUTHOR]

Introduction: Bacteria have been implicated in the development of pouchitis after ileal pouch anal anastomosis. The change in gastric pH with the use of proton pump inhibitors and H antagonists may lead to alteration of enteric bacteria. We hypothesized that chronic use of these medications would decrease the incidence of pouchitis. Methods: Patients who had undergone ileal pouch anal anastomosis for ulcerative colitis were classified by history of pouchitis. Patients were further classified by their use of proton pump inhibitors, H blockers, antacids, and other known risk factors for pouchitis. Results: Eighty-five patients were identified. There was a statistically significant increase in the use of daily acid suppression in patients without pouchitis. There was also a statistically significant increase in the use of antacids in patients without pouchitis. Occasional use of acid suppression did not alter the rate of pouchitis. Conclusions: Our data suggest that the daily use of proton pump inhibitors, H antagonists, or antacids is associated with a decreased risk of pouchitis in ulcerative colitis. Occasional use of these agents did not seem to afford the same protection. These data suggest that altering the pH of the gastrointestinal tract may influence the development of pouchitis. [ABSTRACT FROM AUTHOR]

Clostridium difficile infection (CDI) is currently a leading cause of antibiotic and health care-related diarrhea. The incidence and the severity of CDI-related diarrhea have increased dramatically in the USA and Europe in the past few decades. The emergence of multidrug-resistant hypervirulent strains of C. difficile has led to an increase in mortality. Fecal microbiota transplantation (FMT) (also known as fecal bacteriotherapy) has been utilized sporadically since the 1950s; and currently, the interest in using FMT has grown again in the past few years for the treatment of CDI and other chronic gastrointestinal diseases. FMT has shown to be effective, cheap, and has very few side effects. It is believed to manipulate and restore the gut microbiota, and therefore enhances the growth of "healthy" bacteria that break the cycle of recurrent CDI. This article focus on the recent case reports on FMT, and general approach to patients undergoing this therapy. Data were obtained through a literature search via PubMed and Google. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the effects of supplementing animal feed with a liquid and spray-dried fucoidan and laminarin extract, derived from the seaweed Laminaria digitata on the porcine gastrointestinal microbiota, specifically the communities of Lactobacillus, Bifidobacterium and enterobacteria were evaluated. Twenty four piglets were fed one of three diets over a 21-day period to determine the effect that each had on the bacterial communities. The dietary treatments were as follows; (1) control diet, (2) control diet plus spray-dried formulation of laminarin fucoidan (L/F-SD) extract, (3) control diet plus a liquid formulation of (L/F-WS) extract. Control diet consisted of wheat, soya bean meal, soya oil and a vitamin and mineral mixture. The L/F-SD and L/F-WS supplemented diets had equal proportion of 500 ppm laminarin and fucoidan. At the end of the 21 day feeding period all animals were sacrificed and samples were collected from the ileum, caecum and colon. Counts were determined for Lactobacillus, Bifidobacterium and enterobacteria. Plate count analysis revealed that the L/F-SD diet caused a statistically significant 1.5 log and 2 log increases in the Lactobacillus and Bifidobacterium counts of ileum samples respectively. A greater difference was observed with the L/F-WS diet in that Lactobacillus and Bifidobacterium increased by 2 log and 3 log respectively. Alterations in the Lactobacillus species composition of the gastrointestinal tract (GIT) were analysed using specific PCR - denaturing gradient gel electrophoresis (PCR-DGGE). The DGGE profiles indicated that Lactobacillus species richness decreased along the gastrointestinal tract i.e. the number of dominant species detected in the colon was less than those detected in the ileum and caecum irrespective of the diet consumed. Consumption of both the L/F-SD and L/F-WS diets resulted in a richer Lactobacillus species composition in the ileum, with the L/F-SD diet being associated the emergence of Lactobacillus agilis in the colon. The study indicated that the L/F-WS extract was superior to the L/F-SD extract in increasing the titre of beneficial bacteria in the gastrointestinal tract (GIT). [Copyright &y& Elsevier]

Multidrug-resistant (MDR) Gram-negative bacteria have emerged as a serious threat to human and animal health. Bdellovibrio spp. and Micavibrio spp. are Gram-negative bacteria that prey on other Gram-negative bacteria. In this study, the ability of Bdellovibrio bacteriovorus and Micavibrio aeruginosavorus to prey on MDR Gram-negative clinical strains was examined. Although the potential use of predatory bacteria to attack MDR pathogens has been suggested, the data supporting these claims is lacking. By conducting predation experiments we have established that predatory bacteria have the capacity to attack clinical strains of a variety of ß-lactamase-producing, MDR Gram-negative bacteria. Our observations indicate that predatory bacteria maintained their ability to prey on MDR bacteria regardless of their antimicrobial resistance, hence, might be used as therapeutic agents where other antimicrobial drugs fail. [ABSTRACT FROM AUTHOR]

Recent insights in medical science indicate that human biofilms play an important role in health and well-being, and have put microbiota modulation through bacteriotherapy into focus. In dentistry, bacterial interference with probiotic bacteria to support the stability and diversity of oral biofilms has gained similar interest. Investigations in vitro into metabolic activity, co-aggregation, growth inhibition, bacteriocin production, and adhesion have collectively suggested a potential role for probiotic lactobacilli and bifidobacteria to modulate the oral microbial ecology. Likewise, short-term clinical studies with intermediate microbial endpoints indicate that interference with caries-associated bacteria seems possible through probiotic dairy products, tablets, lozenges and chewing gum in various dose regimens. Few randomized controlled clinical trials with caries outcomes are available, but three studies with preschool children and the elderly have demonstrated preventive fractions between 21% and 75%, following regular intake of milk supplemented with probiotic lactobacilli. However, further large-scale trials with orally derived anti-caries candidates are needed before we can say that we are ready for bacteriotherapy as an adjunct to complement the existing evidence-based methods for preventing and controlling caries in daily practice. [ABSTRACT FROM AUTHOR]

Background: The emergence and the spread of metallo-beta-lactamases (MBLs) in non fermenters like Pseudomonas aeruginosa and the Acinetobacter spp has become a therapeutic challenge. In this study, the phenotypic confirmation of the MBL production was done by different methods. Method: The isolates were screened for metallo-beta-lactamase production by using imipenem. All the imipenem resistant isolates were further subjected to a phenotypic confirmation by the combined disk method, the double disk synergy test and the modified Hodge test. The results were analyzed and tabulated. Results: Of the total 200 isolates, 124(62%) were of P. aeruginosa and 76(38%) were of the Acinetobacter spp. Out of the 200 isolates, 28 (19(68%)- P. aeruginosa and 9(32%)- Acinetobacter isolates were found to be MBL producers by the combined disk test which used imipenem and EDTA , by the double disk synergy test and by the modified Hodge test. But the combined disk test which used ceftazidime detected only 25 out of the 28 MBLs. Conclusion: The results of our study showed that the combined disk test which used imipenem, the double disk synergy test and the modified Hodge test, all had equal sensitivity. But when the ease of the performance and the interpretation of the results were considered cost effectively, the combined disk test was found to be a more feasible option than the other tests. Overall, these tests can be done easily as they are less laborious and are cost - effective. Hence, the routine testing of the metallo beta-lactamase producers is of great value, in order to take measures to advocate a proper antibiotic policy and also to take effective steps for controlling their spread worldwide. [ABSTRACT FROM AUTHOR]

Lactic acid bacteria (LAB) are generally regarded as safe (GRAS) microorganisms and widely used in industry and medicine. We are trying to add additional properties to them by gene engineering. However, the genetically modified bacteria are not acceptable to use in food and medicine due to the presence of antibiotic resistance genes in plasmids. Thus, it is necessary to develop food-grade selection markers. Food-grade markers can be divided into three classes based on their selected characteristics: dominant, complementary and sugar fermentation markers. The developments on these food-grade selection markers were reviewed in order to provide valuable references for the further study. [ABSTRACT FROM AUTHOR]

Bacteria resistance to antibiotics has become a worldwide problem impacted partly by antibiotics use in livestock production. The present study investigated the pattern and mechanisms of resistance in 21 bacteria species isolated from a river used as a waste-dump by a poultry farm in Ogbomoso, southwestern Nigeria. Bacteria were isolated on nutrient agar supplemented with 50 µg/mL of tetracycline, their identities were determined by PCR amplification, and sequencing of their 16s rRNA genes and their susceptibility to 6 antimicrobials determined by broth dilution. The molecular basis of resistance among the isolates was also investigated by the PCR amplification of class 1 and 2 integrons, tetA, tetB, tetC, tetD, tetE, tetG, tetL, tetW, tetM, tet37, blaTEM, aadA1, strA, strB, sul2, sul3 and a 550bp gene fragment encoding a multidrug resistance efflux transporter of the resistance nodulation division (RND) family. All the isolates were resistant to the tested antimicrobials with MIC ranging from <16 µg/mL to 512 µg/mL. class 2 integrons tetB, tetC, tetD, tetE, tetG, tetL, tetW, tetM, tet37, aadA1, and sul3 could not be detected in any of the isolates. However, 2 isolates were positive for class 1 integrons, 1 each for blaTEM and tetA, 3 for sul2, and 2 for strA and strB. Seven of the isolates were positive for the RND efflux pump. Results of the present study showed that polluted aquatic ecosystems may serve as a reservoir of transferable antibiotic resistance. [ABSTRACT FROM AUTHOR]

Periodontitis is one of the most common chronic inflammatory diseases. The etiology is clearly bacterial and a number of putative bacterial pathogens have been associated with the disease, including Aggregatibacter actinomycetemcomitans, Tannerella forsythus and Porphyromonas gingivalis. Comparatively, little attention has been paid to the identification of health-associated and potentially beneficial bacterial species that may reside in the gingival sulcus. Probiotic technology represents a breakthrough approach to maintaining oral health by using natural beneficial bacteria, commonly found in healthy mouths, to provide a natural defense against those bacteria which are thought to be harmful to teeth and gums. This article endeavors to introduce the concepts of probiotics in periodontics. [ABSTRACT FROM AUTHOR]

Background In this study, we have investigated the chemotherapeutic potential of a purple violet pigment (PVP), which was isolated from a previously undescribed Antarctic Janthinobacterium sp. (Ant5-2), against murine UV-induced 2237 fibrosarcoma and B16F10 melanoma cells. Methods The 2237, B16F10, C50, and NIH3T3 cells were treated with PVP at different doses and for different times, and their proliferation and viability were detected by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Cell cycle arrest induced by PVP in 2237 fibrosarcoma cells was assessed by flow cytometry and expression analysis of cell cycle regulatory proteins were done by Western blot. Apoptosis induced by PVP in 2237 cells was observed by annexin-V/propidium iodide double staining flow cytometry assay and fluorescence microscopy. To further determine the molecular mechanism of apoptosis induced by PVP, the changes in expression of Bcl-2, Bax and cytochrome c were detected by Western blot. The loss of mitochondrial membrane potential in PVP treated 2237 cells was assessed by staining with JC-1 dye following flow cytometry. Caspase-3, Caspase-9 and PARP cleavage were analyzed by Western blot and Caspase-3 and -9 activities were measured by colorimetric assays. Results In vitro treatment of murine 2237 cells with the PVP resulted in decreased cell viability (13-79%) in a time (24-72 h) and dose (0.1-1 μ m)-dependent manner. The PVP-induced growth inhibition in 2237 cells was associated with both G0/G1 and G2/M phase arrest accompanied with decrease in the expression of cyclin dependent kinases (Cdks) and simultaneous increase in the expression of cyclin dependent kinase inhibitors (Cdki) - Cip1/p21 and Kip1/p27. Further, we observed a significant increase in the apoptosis of the 2237 fibrosarcoma cells which was associated with an increased expression of pro-apoptotic protein Bax, decreased expression of anti-apoptotic proteins Bcl-2, disruption of mitochondrial membrane potential, cytochrome c release, activation of caspase-3, caspase-9 and poly-ADP-ribose-polymerase (PARP) cleavage. Conclusions We describe the anti-cancer mechanism of the PVP for the first time from an Antarctic bacterium and suggest that the PVP could be used as a potent chemotherapeutic agent against nonmelanoma skin cancers. [ABSTRACT FROM AUTHOR]

Background Airborne microbial products have been reported to promote immune responses that suppress asthma, yet how these beneficial effects take place remains controversial and poorly understood. Methods We exposed mice to the bacterium Escherichia coli and subsequently induced allergic airway inflammation through sensitization and intranasal challenge with ovalbumin. Results Pulmonary exposure to the bacterium Escherichia coli leads to a suppression of allergic airway inflammation. This immune modulation was neither mediated by the induction of a T helper 1 (Th1) response nor regulatory T cells; however, it was dependent on Toll-like receptor 4 (TLR4) but did not involve TLR desensitisation. Dendritic cell migration to the draining lymph nodes and activation of T cells was unaffected by prior exposure to E.coli, while dendritic cells in the lung displayed a less activated phenotype and had impaired antigen presentation capacity. Consequently, in situ Th2 cytokine production was abrogated. The suppression of airway hyper-responsiveness was mediated through the recruitment of gd T cells; however, the suppression of dendritic cells and T cells was mediated through a distinct mechanism that could not be overcome by the local administration of activated dendritic cells, or by the in vivo administration of tumour necrosis factor a. Conclusion Our data reveal a localized immunoregulatory pathway that acts to protect the airways from allergic inflammation. [ABSTRACT FROM AUTHOR]

The article offers information on the benefits offered by probiotics/direct-fed microbials (DFMs) to both human and animal's health. It states that probiotics/DFMs protect the gastrointestinal (GI) system against pathogens by preventing them from attaching to the intestinal lining, and studies have shown that probiotics/DFMs work via competitive inhibition. Also, probiotics/DFMs aid in digestion and treat several GI diseases such as inflammatory bowel disease and diarrhea. It notes that the administration probiotics/DFMs will maintain the health of food animals and the health of those who consume the animal products.

Rhamnolipid biosurfactants are effective antimicrobial agents and provide a promising alternative to synthetic medicine. Rhamnolipid accumulation by Pseudomonas aeruginosa ATCC 9027, and associated antimicrobial activity, was quantified during phosphate limited culture. The onset of rhamnolipid production occurred below 0.35 mg phosphate/l. Thereafter rhamnolipid accumulated during phosphate exhaustion where nitrogen remained above 0.9 g/l. A maximum 4.261 g rhamnolipid/l (measured as 1.333 g rhamnose/l) was attained at a productivity of 0.013 g rhamnose/l/h. Rhamnolipid accumulation under conditions of phosphate exhaustion and nitrogen excess suggests a non-specificity of the limiting nutrient, and that rhamnolipids will be synthesised provided carbon is in excess of the metabolic capacity. Antimicrobial activity was demonstrated against Mycobacterium aurum, a surrogate for M. tuberculosis, the causal agent of most forms of tuberculosis, by a 45 mm zone of M. aurum inhibition around a well of supernatant containing 3.954 g rhamnolipid/l. [ABSTRACT FROM AUTHOR]

Streptomyces 23-2B is one of actinomycetes associated with marine clam Donax trunculus and has potential source of bioactive metabolites, which possesses a broad spectrum antibiotic and anticancer activities. This study aims to evaluate the effect of Streptomyces 23-2B metabolites on hepatic lipid peroxidation (LPO), reduced glutathione (GSH) levels, as well as serum uric acid, total cholesterol (TC), triglyceride (TG), nitric oxide (NO) and tumor necrosis factor-alpha (TNF-α) levels of rat. Animals were divided into four groups: the control group, which received 0.1 ml of 10% Tween-80 by intraperitoneally injection, and the other three experimental groups, which received 10% Tween 80 solution of Streptomyces 23-2B metabolites in doses of 0.5, 5 and 50 mg/kg body weight at an interval 2 days for 2 weeks. LPO levels showed significant decrease with the lowest doses. The effect at a dose of 50 mg/kg of Streptomyces 23-2B metabolites on TG was more pronounced than the other two doses (0.5 and 5 mg/kg body weight). Hypocholesterolemia was recorded in the treated rats with 0.5 and 5 mg/kg of Streptomyces 23-2B. However, the highest dose enhanced the elevation of serum TNF-α and NO levels. Thus, the present study reveals that Streptomyces 23-2B metabolite is a newly discovered biomaterial from microorganisms. The novel substance showed inhibitory activity against LPO in rat liver homogenate and improving the immune response by releasing TNF-α and NO in serum. [ABSTRACT FROM AUTHOR]

Bacterial therapies possess many unique mechanisms for treating cancer that are unachievable with standard methods. Bacteria can specifically target tumours, actively penetrate tissue, are easily detected and can controllably induce cytotoxicity. Over the past decade, Salmonella, Clostridium and other genera have been shown to control tumour growth and promote survival in animal models. In this Innovation article I propose that synthetic biology techniques can be used to solve many of the key challenges that are associated with bacterial therapies, such as toxicity, stability and efficiency, and can be used to tune their beneficial features, allowing the engineering of 'perfect' cancer therapies. [ABSTRACT FROM AUTHOR]

It is well-known that bacteria can produce compounds which show anticancer effects. In present time, it is impossible to check all bacterial species on their possible production of anticancer compounds (AC) under different conditions. Thus, it is necessary to limit the area for search of bacterial products for the anticancer therapy. We propose that production of AC by bacteria is a part of microbial biological strategy under natural conditions. We propose that bacteria in soils, in water and on plants do not meet human tumors and their AC serve for the competition with eukaryotic organisms. Most probably, an epiphytic growth of bacilli is accompanied with production of compounds inhibiting eukaryotes. According to awaited profit for the AC-producing bacteria, the epiphytic groups of bacilli show inhibition of mycelial fungi which are a natural model of eukaryotic cells. An example of strain isolation and a primary test is presented. [ABSTRACT FROM AUTHOR]

Fusarium root rot is an important disease of soybean in Ontario, Canada. This study is to select antagonistic bacterial agents as effective alternatives to chemical pesticides for the control of root rots caused by Fusarium oxysporum and F graminearum. Twenty-two Bacillus subtilis strains from soybean and corn roots were tested in dual cultures for inhibition of mycelial growth of F oxysporum and F graminearum. All strains significantly reduced mycelial growth of F oxysporum by approximately 17 to 48% and of F graminearum by 10 to 32%. Ten B. subtilis strains selected based on their larger fungal inhibition zones were evaluated against macroconidial germination. These strains inhibited the spore germination of F oxysporum by 20 to 48% and of F graminearum by 14 to 32% in cell-free filtrates. Under greenhouse conditions, the efficacy of seed and soil treatments with B. subtilis strains against the two Fusarium root rot pathogens was evaluated based on root rot severity, seedling emergence, plant height, and root dry weight. Six B. subtilis strains (SBO1, SBO4, SB23, SB24, SB28, and SB33) from soybean roots and two strains (CBO I and CH22) from corn roots significantly reduced the severity of the two Fusarium root rots in seed or soil treatments. Strains SBOI, SBO4, SB23, and SB24 were the most effective treatments against both pathogens in either seed or soil treatment. When applied as seed treatments, these four strains reduced root rot severity by 43 to 63% and increased emergence by 13 to 17%, plant height by 9 to 18%, and root dry weight by 8.4 to 19%. When used as soil treatments, they reduced root rot severity by 68 to 74% and increased emergence by 14 to 18%, plant height by 11 to 23%, and root dry weight by 16 to 24%. These results suggest that the novel strains of B. subtilis identified in this research can be effective alternatives to fungicides in managing Fusarium root rots of soybean, and a greater level of efficacy may be achieved when they were used as soil treatments than seed treatments. [ABSTRACT FROM AUTHOR]

Bdellovibrio species are naturally predatory, small, motile, Deltaproteobacteria that invade the periplasm of other larger gram-negative bacteria, killing and digesting them. Bdellovibrio grows and divides inside the prey cell, in a structure called a bdelloplast, which then lyses, releasing the Bdellovibrio to prey upon more bacteria. This capability makes Bdellovibrio a potential therapeutic agent, but since its discovery in the 1960s it has not been applied in this way. This review considers what is known postgenomically about Bdellovibrio and its predatory lifestyle, drawing also from what was learned by the excellent microbial physiology work of the early Bdellovibrio researchers. Recent work on the diversity and evolution of predatory bdellovibrios, the role of surface structures in predation, and the ongoing questions about how Bdellovibrio switches between axenic and predatory growth and how its predatory activities may be tempered in the wild, as well as suggestions for future research priorities, are discussed. [ABSTRACT FROM AUTHOR]

Although human consumption of Bacillus polyfermenticus provides several health benefits, the probiotic effect of this bacterium against colonic inflammation has not yet, to our knowledge, been studied. Therefore, we induced colitis in mice by oral or intrarectal administration of dextran sodium sulfate (DSS) or trinitrobenzenosulfonic acid ITNBSI, respectively, and investigated the effect of B. polyfermenticus on colitis. We found that mice treated with DSS or TNBS along with B. polyfermenticus had reduced mortality and severity of colitis lweight loss, diarrhea, and mucosal damages) than mice treated with DSS or TNBS alone. B. polyfermenticus also reduced the expression of inflammatory molecules, including chemokine (C-X-C motif) ligand 1, intercellular adhesion molecule, and tumor necrosis factor-α, but enhanced the expression of the antiinflammatory cytokine interleukin-10 in the inflamed mouse colon. Moreover, B. polyfermenticus suppressed apoptosis both in vivo in inflamed colonic mucosa and in vitro in colonic epithelial cells stimulated with apoptosis-inducing agents (FasL or Clostridium difficile Toxin A) when the apoptotic response was determined by a terminal deoxynucleotidyl transferase dUTP nick end labeling assay and cleavage of poly(ADP-ribose) polymerase or caspase-3, respectively. Treating colonic epithelial cells with B. polyfermenticus-conditioned medium (BPCM) enhanced cell proliferation and induced the phosphoinositide 3-kinases/Akt signaling pathway, suggesting that this bacterium can promote epithelial cell proliferation. BPCM also promoted the migration of colonic epithelial cells. These data suggest that B. polyfermenticus ameliorates colonic inflammation by suppressing apoptosis and promoting epithelial cell proliferation and migration. [ABSTRACT FROM AUTHOR]

Enterococci are indicator bacteria used to assess the risk of acquiring enteric disease from swimming in marine waters. Previous work identified beach sands as reservoirs of enterococci which can be transported from the sand to the sea, where they may instigate beach advisories. The present study establishes that naturally occurring enterococci can replicate in beach sands under environmentally relevant conditions. In unseeded, nonsterile microcosm experiments, it was shown that intermittent wetting of sands by seawater, like that which would occur at the high tide line, stimulates the transient replication of enterococci at rates of 0.20 to 0.63 per day (equivalent to doubling times of 1.1 to 3.5 days). Replication was not observed in control microcosms that were not subjected to wetting. Enterococci were enumerated using both culture-dependent (membrane filtration and mEI media) and culture-independent (quantitative PCR [QPCR], 23S rRNA gene based) techniques, which allowed tracking of both culturable and total enterococcus populations. Inhibition of QPCR and DNA extraction efficiencies were accounted for in the interpretation of the QPCR results. The results provide evidence that enterococci may not be an appropriate indicator of enteric disease risk at recreational beaches subject to nonpoint sources of pollution. [ABSTRACT FROM AUTHOR]

In low-pathogenic avian influenza (LPAI) virus, the effects of prophylactic oral administration of Lactobacillus plantarum KFCC11389P on immunity, viral loads and levels of nitric oxide and interferon-γ in splenocytes from specific pathogen free (SPF) chickens were investigated. For in vitro screening of the antiviral effect, haemagglutination activities of four different lactic acid bacterial strains by direct contact with virus were measured. L. plantarum KFCC11389P only neutralized the virus on the SPF eggs. For in vivo studies, four groups of chickens were fed with various L. plantarum KFCC11389P bacterial components and were then challenged with LPAI virus at 28 days. Additionally, two control groups were used as negative (virus-unchallenged) control and positive (virus-challenged) control. We show that some parameters such as nitric oxide production in serum and splenic adherent cells and interferon-γ levels in splenic cells from SPF chickens could be used for the evaluation of LPAI virus infection. This is the first report demonstrating the interferon-γ production in cultured splenic mononuclear cells and nitric oxide production in serum as well as virus shedding in trachea and cloacae in LPAI virus-infected SPF chickens fed specific lactic acid bacterial components. [ABSTRACT FROM AUTHOR]

Background A major obstacle in treatment of solid tumors is the inefficient delivery of therapeutic agents to the hypoxic cores. Hypoxia offers the potential for anaerobic bacteria colonization and tumor destruction by the bacteria, and dormant spores of wild-type Clostridium perfringens (Cp) germinate and proliferate within the hypoxic cores of pancreatic tumors in mice. However, the oncopathic effects of Cp were limited by host inflammatory responses and by Cp's residual tolerance to oxygen, which caused toxic effects in animals. Methods Recombinant Cp strains in which superoxide dismutase, a major oxygen tolerance gene, was deleted (Cp/ sodj were constructed to enhance its selective growth in tumors. In addition, Panton-Valentine Leukocidin (PVL), an inflammation-suppressing gene from Staphylococcus aureus, was inserted into the Cp/sod genome to enhance its oncopathic potency. The ability of the recombinant Cp strains to kill tumors was investigated in C57/BL6 mice bearing murine PANCO2 tumors. Systemic and organ toxic effects were assessed by monitoring serum chemistries and histopathological examination. Statistical tests were two-sided. Results Cp/sodshowed reduced toxic effects compared with wild-type Cp when spores were administered intravenously into PANCO2 tumor-bearing mice. Mice treated with Cp/sod/PVL spores demonstrated a reduction in neutrophils and macrophages in tumors, logarithmically elevated growth of intratumoral bacteria, enhanced tumor necrosis, and substantially prolonged survival without apparent systemic and organ toxic effects, compared with mice treated with both wild-type Cp and Cp/sodspores. Accordingly, 47% of Cp/ sod-/PVL-treated mice (n = 15) achieved tumor-free survival for over 120 days, whereas all mice treated with Cp/sod or phosphate-buffered saline (n = 10 per group) died within 50 days. The median survival for Cp/sod/PVL-treated mice was 77 days (95% confidence interval [I] = 45 to 120 days) and for Cp/sodtreated mice was 30 days (95% Cl = 23 to 36 days; P< .001). Conclusions Cp/sodVPVL provides a prototype for a novel class of oncopathic microbes that may have potential for the safe and effective treatment of pancreatic cancer and other poorly vascularized tumors. [ABSTRACT FROM AUTHOR]

The effect of starter cultures Lactobacillus plantarum (A6), Lactobacillus fermentum (OgiE-1) and natural inoculum (NI) on some physicochemical properties of cofermented maize–cowpea (CMCO) was investigated. Crude protein, lipid, ash, crude fiber, carbohydrate energy and utilizable energy because of protein contents of CMCO fermented with A6 (A6MC), OgiE-1 (OGMC) and NI (NIMC) are 12.46–13.74%, 3.58–4.96%, 1.06–1.85%, 3.06–4.62% and 66.81–68.30%, 355.26–363.2 kcal/100 g and 7.43–9.14%, respectively. Mineral contents were significantly higher in A6MC and OGMC. [K/Na], [Ca/P] and [Ca/Mg] ratios range between 9.51 and 22.22, 0.02 and 0.12 and 0.16 and 1.02, respectively. Oligosaccharides reduced significantly in A6MC and OGMC. The pH values of A6MC, OGMC and NIMC range between 6.4 and 4.5, 6.4 and 5.5 and 6.4 and 5.2, respectively. Titratable acidity and total phenol increased, while phytates decrease. Viscosity increased with flour concentration up to 9% in OGMC, and A6MC increased in NIMC. A6MC gave the best overall results. PRACTICAL APPLICATIONS This work adds to the existing database on the potential usefulness of starter cultures in the development of nutritionally balanced diets, particularly in developing economies. It also stimulates increased interest in the use of Lactobacillus plantarum A6 in new product development for addressing the prevailing food situation in many parts of the world. Findings from this work will further encourage basic and applied research on L. plantarum and other organisms with potential for use as starter cultures from different areas of the world. [ABSTRACT FROM AUTHOR]

Lactobacillus acidophilus was entrapped in κ-carrageenan and used to perform tomato juice fermentation in order to raise the survival of the bacteria in the product. Gel beads with diameters approximately 3.0 mm for cell immobilization were obtained, fresh raw tomatoes were used to make the juice and both free and immobilized cells were applied to carry out the fermentation for 80 h. Cell leakage from the gel beads and proliferation in the juice during the fermentation of immobilized cells were observed. The final viable cell number was attained with 107 cfu/mL in the juice, over 1010 cfu/mL-gel in gel beads for the fermentation of immobilized cell, and ca. 109 cfu/mL for the free cell. Immobilized cells could withstand the unfavorable low pH environment in tomato juice and better growth was achieved compared with free cells. The viable cell counts of immobilized L. acidophilus in the fermented tomato juice could maintain the level of 106 cfu/mL-gel after 10 weeks of cold storage at 4C, in comparison with 104 cfu/mL for free cells. The immobilized cell fermented tomato juice also showed better overall palatability than that of free cells in cold storage at 4C. PRACTICAL APPLICATIONS This study demonstrates the applicability of κ-carrageenan immobilized Lactobacillus acidophilus in the fermentation of tomato juice. The unfavorable low pH condition in tomato juice could be overcome and certain benefits were provided by cell immobilization. [ABSTRACT FROM AUTHOR]

The lithistid sponge Discodermia dissoluta (family Theonellidae), is found in deep-waters throughout the Caribbean sea and is the source of discodermolide, a natural product with potential anticancer properties, and other secondary metabolites. As with other sponges, large numbers of microbes are harbored in the sponge mesohyl. The microbial population of the sponge mesohyl shows an abundance of large filamentous microbes. Fractionation of the dissociated sponge allowed enrichment of this microbe, which was then identified by analysis of the 16S rRNA genes. Its identity was confirmed through the use of fluorescent in situ hybridization. These studies have allowed the identification of this eubacterial microbe as belonging to the genus Entotheonella.The ISME Journal (2008) 2, 335–339; doi:10.1038/ismej.2007.91; published online 7 February 2008 [ABSTRACT FROM AUTHOR]

Abstract: The redox transformation and mobility of arsenic in spent adsorbents under reducing conditions were studied using an incubation test with mixed reducing bacteria, high-performance liquid chromatography-atomic fluorescence spectrometry for speciation of soluble arsenic (As), and thermodynamic calculations. The spent adsorptive media, including granular ferric hydroxide, granular ferric oxide, titanium dioxide, activated alumina and modified activated alumina, were collected from pilot-scale filters that were tested for removal of arsenate [As(V)] from groundwater in New Jersey, USA. During 65 days of incubation of the spent adsorbents with nutrient media in closed containers, the electron activity, pe, was reduced from about 1.7 to −7. Meanwhile, reduction of Fe(III) to Fe(II), As(V) to arsenite [As(III)], and sulfate to sulfide occurred. Less than 4% total As was released from iron-based media in the pe range between −3 and −7 due to reduction of As(V) to As(III) and reductive dissolution of ferric (hydr)oxides. Up to 38% As was released from the TiO2 adsorbent, which occurred at extremely low redox potential (i.e., pe<−6). The findings of this study will improve our ability to predict arsenic mobility when As-containing spent media are disposed of in landfills and the environment. [Copyright &y& Elsevier]

Encapsulated bacteria are responsible for the majority of mortality among neonates and infants. The major components on the surface of these bacteria are polysaccharides which are important virulence factors. Immunity against these components protects against disease. However, most of the polysaccharides are thymus-independent (TI)-2 antigens which induce an inadequate immune response in neonates and infants. The mechanisms that are thought to play a role in the unresponsiveness of this age group to TI-2 stimuli will be discussed. The lack of immune response may be overcome by conjugating the polysaccharides to a carrier protein. This transforms bacterial polysaccharides from a TI-2 antigen into a thymus-dependent (TD) antigen, thereby inducing an immune response and immunological memory in neonates and infants. Such conjugated vaccines have been shown to be effective against the most common causes of invasive disease caused by encapsulated bacteria in neonates and children. These and several other approaches in current vaccine development will be discussed. [ABSTRACT FROM AUTHOR]

Objectives: Microbicides are products in development to prevent sexually transmitted infection and HIV acquisition; they are not yet available to the public. We evaluated (1) where women would expect to seek information about microbicides, (2) factors that women think might affect microbicide effectiveness, and (3) women's anticipated preferences for timing and place of insertion and partner involvement. Methods: A cross-sectional face-to-face interview was administered to women aged 18–35 years ( n = 126) recruited from a gynecology clinic in Galveston, Texas. Women were shown a microbicide surrogate and asked to complete a series of closed-ended questions focusing on demographics, expected sources of information on microbicides, perceived factors related to effectiveness, and preferences for timing and place of insertion and level of partner involvement. Univariate descriptive analyses were used to calculate means, medians, and frequencies. Results: Women's most cited anticipated sources of information for microbicides were physicians (89%), the package insert/box (86%), and pharmacists (70%). Approximately two thirds of the women believed that menstruation or taking other medicines and approximately one third believed that taking a bath/shower before intercourse or after intercourse or using birth control medication could limit effectiveness. Women anticipated preferring to insert the microbicide before intercourse (90%) and while in the bathroom (73%). Most (95%) anticipated telling their partners they planned to use a microbicide, and 38% anticipated having their partner insert the product for them. Conclusions: Women's beliefs about those factors that could limit effectiveness of micro bicides should be addressed as part of anticipatory guidance or in the package inserts. Partners likely will be involved in the use of microbicides; thus, education/marketing efforts should also incorporate partner beliefs and preferences. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To evaluate the use of a multiprobe fluorescent in situ hybridization (FISH) assay for determining the response of patients with high-risk superficial bladder tumour (HRSBT) to bacillus Calmette-Guérin (BCG) therapy. Methods: Bladder washing specimens from 65 HRSBT patients collected before and after BCG therapy were analyzed by FISH. Labelled probes for chromosomes 3, 7, 9, and 17 were used to assess chromosomal abnormalities indicative of malignancy. Results: Fifty-five of 65 (85%) patients had a positive pre-BCG FISH result; 29 (45%) patients had a positive and 36 (55%) had a negative post-BCG FISH result. Patients with a positive post-BCG FISH status had a 2.7 times higher risk for tumour recurrence than patients with a negative post-BCG FISH status (p =0.017; 95% CI: 1.18–6.15). In addition, patients who maintained a positive FISH status before and after BCG therapy had a risk for tumour recurrence 2.96 times higher than patients whose FISH result changed from positive to negative after BCG (p =0.02; 95% CI: 1.17–7.54). On the other hand, there was no significant difference between the risk for tumour progression in patients with a positive versus a negative post-BCG FISH result (p =0.49). Conclusions: The high percentage of positive pre-BCG FISH results suggests the need for adjuvant therapy in patients with HRSBT after the initial transurethral resection. In addition, patients with a positive post-BCG FISH result were more likely to relapse after therapy. Thus, FISH appears to be useful for the surveillance of patients with HRSBT following BCG therapy. [Copyright &y& Elsevier]

The article focuses on strategies to modulate the gut microbiota in humans. Strategies include fecal microbiota transplant (FMT), which has shown results in treating several disease conditions. Some of the factors to be taken into account during the modulation of the gut microbiota include the preparative regimen, measurement of engraftment of gut microbes and concurrent dietary intake.

Interleukin-10 (IL-10) is a promising candidate for the treatment of inflammatory bowel disease. Intragastric administration of Lactococcus lactis genetically modified to secrete IL-b in situ in the intestine was shown to be effective in healing and preventing chronic colitis in mice. However, its use in humans is hindered by the sensitivity of L. lactis to freeze-drying and its poor survival in the gastrointestinal tract. We expressed the trehalose synthesizing genes from Escherichia coli under control of the nisin-inducible promoter in L. lactis. Induced cells accumulated intracellular trehalose and retained nearly 100% viability after freeze-drying, together with a markedly prolonged shelf life. Remarkably, cells producing trehalose were resistant to bile, and their viability in human gastric juice was enhanced. None of these effects were seen with exogenously added trehalose. Trehalose accumulation did not interfere with IL-10 secretion or with therapeutic efficacy in murine colitis. The newly acquired properties should enable a larger proportion of the administered bacteria to reach the gastrointestinal tract in a bioactive form, providing a means for more effective mucosal delivery of therapeutics. [ABSTRACT FROM AUTHOR]

Probiotics is a field of science, medicine and business that is growing rapidly. Regulatory agencies, especially in North America, are slow to understand these concepts and embrace and enforce United Nations and World Health Organization Guidelines. In order to advance the science and efficacy of probiotics, industry needs to self-regulate and ensure that high standards of products are met, then trials must be performed on human subjects using appropriate sample size, design and target population. With the support of granting agencies, such studies will provide valuable information on the efficacy and limitations of probiotics, and the mechanisms by which they confer their activity. In addition, regulatory authorities need to establish and enforce a 'standard of identity' and only allow products to be called probiotic if sufficient documentation is generated. [ABSTRACT FROM PUBLISHER]

Focuses on the use of live bacteria in the treatment of cancer. Tumor necrosis factor alpha; Bacillus-Calmette-Guerin-induce cellular cytotoxicity.

Discusses the role of pre- and probiotics in promoting health and treating disease. Details on probiotic bacteria; Mechanisms of immunomodulation, cholesterol regulation and cancer prevention through probiotics; Diseases treated by probiotics.

Provides information on acute poststreptococcal glomerulonephritis (APG). Therapeutic use of an antimicrobial treatment of group A beta-hemolytic streptococcal tonsillopharyngitis; Clinical representations of APG; Consideration of streptococcal strains as rheumatogenic.

This article discusses the treatment of Clostridium difficile via fecal microbiota transplantation (FMT). The authors comment on the effectiveness of FMT, as it provides an antibiotic-free therapy for those suffering from C. difficile. They also consider the chances of recurrence of disease after a successful transplant.

The article discusses scientific aspects of interactivity of microbiomes and interplay between microorganisms derived from archaea, bacteria and fungi. These aspects could inspire the future course of biotechnology. The synergistic microbiomes showing relationships between single microbiomes such as the rhizosphere, the gut microbiome and the indoor microbiome are discussed. The use of advanced biocontrol technologies (ABT) to suppress pathogens is mentioned.

Asserts the potential of probiotic bacteriotherapy in controlling the allergic inflammation associated with food allergy. Clinical evidence for the potential use of probiotics in the management of food allergy; Targets for probiotic therapy in patients with food allergy; Role of lactobacillus GG in promoting gut barrier function and alleviating intestinal inflammation.

Lactic acid-producing bacteria prevent carcinogen-induced preneoplastic lesions and tumors in rat colon. Because the mechanisms responsible for these protective effects are unknown, two strains of lactic acid bacteria, Lactobacillus delbrueckii ssp. bulgaricus 191R and Streptococcus salivarius ssp. thermophilus CH3, that are used to produce yogurt, were investigated in vitro and in vivo to elucidate their potential to deactivate carcinogens. Using the "Comet assay" to detect genetic damage, we found that L. bulgaricus 191R applied orally to rats could prevent 1, 2-dimethylhydrazine-induced DNA breaks in the colon in vivo, whereas St. thermophilus CH3 were not effective. However, in vitro, both strains prevented DNA damage induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in isolated primary rat colon cells. Extracts prepared from milk fermented with St. thermophilus CH3 were as efficient in deactivating MNNG as was L-cysteine. Isolated metabolites arising from bacteria during fermentation in the colon or in milk [L(+) lactate, D(-) lactate, palmitic acid and isopalmitic acid] were not effective. We postulate that thiol-containing breakdown products of proteins, via catalysis by bacterial proteases, could be one mechanism by which MNNG or other carcinogens are deactivated in the gut lumen resulting in reduced damage to colonic mucosal cells. [ABSTRACT FROM AUTHOR]