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ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) and enteric bacteria Shigella dysenteriae, Salmonella typhimurium and Escherichia Coli have been causing increasing nosocomial infections worldwide, contributing to high mortality and morbidity in surgical wards. This study attempts to investigate the feasibility of dieletrophoresis (DEP) electrode in detecting both ESKAPE and enteric bacteria in water samples. The detection is based on the bacteria's response to the non-uniform electric field in micro tapered DEP electrode and microfluidic chamber. Responses of each bacterium were recorded by varying the frequency of sinusoidal 6 voltage (peak to peak) from 10 to 13,000 kHz. Utilising the unique electrokinetic responses of each bacterium, the performance of DEP application is assessed in detecting the ESKAPE and enteric bacteria from samples within the urban water cycle, i.e., wastewater, river, runoff, and treated water from an urbanised developed area. The positive (P DEP) , negative (N DEP) and transitional, (denote as the crossover frequency f x 0) responses for each bacterium were consistently determined, spanning between 52.3 and 12,000 kHz. DEP technique was successfully able to detect ESKAPE and enteric bacteria from water samples, where water from the river proved to be the most microbially contaminated in urban water cycle. [ABSTRACT FROM AUTHOR]

The microalgal biomass obtained from phycoremediation holds great potential for various biotechnological applications. However, it is important to address the issue of potential pathogenic bacterial contamination, which can be present in the wastewater treated during phycoremediation and may coexist with the harvested biomass. This study aimed to investigate the survival of enteric bacteria when present in microalgal biomass stored at temperature ranges that emulate environmental conditions typically found in tropical countries. For that, the biomass was intentionally contaminated with known quantities of Escherichia coli and Salmonella typhimurium. The contaminated biomass was stored at temperatures corresponding to different seasons in tropical countries: 10 °C (winter), 21 °C (spring/autumn), and 35 °C (summer). The results revealed that S. typhimurium was able to survive for 14 days at all tested temperatures. Conversely, E. coli exhibited a reduction of up to 6 log 10 in 21 days when stored under spring and summer temperatures. However, when the biomass was stored at the winter temperature, the reduction in E. coli concentration was only 1 log 10. The time required for 90% inactivation of S. typhimurium (T 90) was determined to be approximately 3.725 days. However, to achieve 90% inactivation of E. coli at 10, 21, and 35 (°C), it took approximately 25.706, 4.217, and 3.906 days, respectively. These findings underscore the critical role of storage temperature in influencing the survival of bacteria over time. It is important to maintain aseptic conditions during the handling and storage of the biomass, particularly considering its intended applications and potential downstream uses. [Display omitted] • Pathogenic bacteria exhibit prolonged persistence within harvested biomass. • During microalgae storage, S. typhimurium inactivated faster than E. coli. • Adequate treatment and storage of microbial biomass are vital for ensuring safety. [ABSTRACT FROM AUTHOR]

To provide for temporary restrictions of the public water supply system, storage tanks are commonly installed in the domestic water systems of houses and apartment buildings in Okinawa Prefecture of Japan. To learn more about the sanitary condition and management of these water supply facilities with storage tanks (hereafter called “storage tank water systems”) and the extent of bacterial contamination of water from these facilities, we investigated their usage and the existence of Aeromonas , enteric and related bacteria. Verbal interviews concerning the use and management of the storage tank water systems were carried out in each randomly sampled household. A total of 54 water samples were collected for bacteriological and physicochemical examinations. Conventional methods were used for total viable count, fecal coliforms, identification of bacteria such as Aeromonas , Enterobacteriaceae and non-fermentative Gram-negative rods (NF-GNR), and measurement of residual chlorine. On Aeromonas species, tests for putative virulence factor and an identification using 16S rRNA and rpoB genes were also performed. Water from the water storage systems was reported to be consumed directly without boiling in 22 of the 54 houses (40.7%). 31 of the sampled houses had installed water storage tanks of more than 1 cubic meter (m 3 ) per inhabitant, and in 21 of the sampled houses, the tank had never been cleaned. In all samples, the total viable count and fecal coliforms did not exceed quality levels prescribed by Japanese waterworks law. Although the quantity of bacteria detected was not high, 23 NF-GNR, 14 Enterobacteriaceae and 5 Aeromonas were isolated in 42.6%, 7.4% and 3.7% of samples respectively. One isolated A. hydrophila and four A. caviae possessed various putative virulence factors, especially A. hydrophila which had diverse putative pathogenic genes such as aer , hlyA , act , alt , ast , ser , and dam . Many bacteria were isolated when the concentration of residual chlorine was below 0.1 mg/l and the water temperature was above 20 °C. These results suggest that elevated water temperature and mismatch between tank size and water demand lead to loss of residual chlorine in tap water. Therefore, to minimize growth of aquatic bacteria such as Aeromonas spp. and Pseudomonas spp., we recommend that an appropriate size tank and/or volume of stored water is always used, and also suggest installation of some means of reducing water temperature such as shading. [ABSTRACT FROM AUTHOR]

This study investigated Enterobacteriales and their antimicrobial resistance in green sea turtles captured adjacent to the central Great Barrier Reef (GBR) and proximate to urban development. Cloacal swabs were taken from 73 green turtles between 2015 and 2016. A total of 154 out of 341 Gram-negative bacterial isolates were identified as Enterobacteriales that represent 16 different species from 9 different genera. The dominant isolates were Citrobacter (30.52%), Edwardsiella (21.43%) and Escherichia (12.34%). The resistance against 12 antibiotics belonging to 6 different classes was determined. The isolates showed highest resistance to β-lactam antibiotics (78.57%) followed by quinolone (50%) and tetracycline classes (46.1%). Approximately one-third (37.7%) of the isolates identified exhibited multidrug-resistance. Isolates recovered from rehabilitated turtles were significantly multidrug resistant (p < 0.009) compared to isolates from other study sites. These results provide baseline information on antimicrobial resistance while revealing gaps for further research to evaluate the level of pollution in the GBR. [ABSTRACT FROM AUTHOR]

A feather-degrading bacterium was isolated from the gut of the tarantula Chilobrachys guangxiensis , and was classified as Bacillus subtilis (named Bacillus subtilis CH-1) according to both the phenotypic characteristics and 16S rRNA profile. The improved culture conditions for feather-degrading were 10.0 g l −1 mannitol, 10.0 g l −1 tryptone, 0.1 g l −1 MgCl 2 , 0.4 g l −1 KH 2 PO 4 , 0.3 g l −1 K 2 HPO 4 , 0.5 g l −1 NaCl, and 2.0 g l −1 intact feather, with pH 8.5 and 37 °C. In the optimized medium, the intact black feather was completely degraded by Bacillus subtilis CH-1 in 24 h. Furthermore, four kinds of enzymes which include extracellular protease Vpr, peptidase T, γ-glutamyl transpeptidase and glyoxalmethylglyoxal reductase were identified as having principal roles. Simultaneously, the relationship between the disulfide bond reducing activity (DRT) and the keratinase activity (KT) in B. subtilis CH-1 fermentation system was discussed. This is the first report for a feather-degrading enteric bacterium from tarantula. The identification of the enzymes shines a light on further understanding the molecular mechanism of feather-degrading by microbes. [ABSTRACT FROM AUTHOR]

The photo-disinfection of water from two different wells (W1, pH: 4.6-5.1 ± 0.02) and (W2 pH: 5.6-5.7 ± 0.02) was carried out during the rainy season at Ouagadougou-Burkina Faso, West Africa. The weather variation during the rainy season significantly affects the photo-disinfection processes (solar disinfection and photo-Fenton). The dilution of the water by rainwater highly affected the chemical composition of the wells' water used in this study; very low iron contents Compared to the ones recorded during the dry season were recorded in all water samples. Both photo-disinfection processes were used to treat 25 L of water in a compound parabolic collector (CPC). None of them have shown the total inactivation of both wild enteric bacteria strains (total coliforms/E. coli and Salmonella spp.) involved in the treatment. However, the total coliforms/E. coli strains were totally inactivated during the exposure under most of the photo-Fenton treatment. Also, the remaining strains, especially those of Salmonella spp. were achieved during the subsequent 24 h of dark storage under the action of the Fenton process. Under uniquely solar radiation, total inactivation was recorded only in the total coliforms/E. coli strains. The impact of the available irradiance on the efficiency of the photo-Fenton disinfection of natural water was highlighted during the exposure under high intermittent solar radiation. The impact of the HCO3- concentration of both wells' water on the evolution of the pH during the photo-disinfection was recorded. Drastic decrease was noticed after the initial fast increase in presence of low HCO3- concentration while a steady state was observed after the increase in presence of higher concentration. The redox activities of the nitrogen components of the water during both photo-disinfection processes have led to increased concentration of nitrite in all the cases and variations were noticed in that of nitrate and ammonia. [ABSTRACT FROM AUTHOR]

Abstract: Iron photo-assisted inactivation of wild enteric bacteria (total coliforms/E. coli and Salmonella spp.) was carried out in water from the Sahelian wells having different pH (W1: 4.9 and W2: 6.3) and a natural iron content of 0.07mg/L. We evaluate the efficiency of the disinfection on different systems containing both or only one Fenton reagent (H2O2/Fe2+): (i) H2O2/Fe2+/hv, (ii) Fe2+/hv, (iii) H2O2/hv, and (iv) only light irradiation (hv) at lab and field scale. Generally, 0.6mg/L of Fe2+ and/or 8.5mg/L of H2O2 were used in the Fenton reagent. The systems H2O2/Fe2+/hv and H2O2/hv led to total inactivation of Salmonella and E. coli. The natural iron content (0.07mg/L) was enough to drive an efficient photo-Fenton process leading to total bacterial inactivation. Our results show that: (i) the iron salt present in Sahelian water is enough to perform a photo-Fenton disinfection of drinking water when adding H2O2, (ii) addition of external iron salts at near neutral pH has no additional effect on the bacterial photo-Fenton inactivation process. After one week of storage, no enteric bacteria re-growth was observed in treated waters. Mechanistic suggestions are presented to explain the observed results. [Copyright &y& Elsevier]

The extremely acidic environment of the mammalian stomach not only serves to facilitate food digestion but also acts as a natural barrier against infections of food-borne pathogens. Many pathogenic bacteria, such as enterohemorrhagic Escherichia coli, can breach this host defense and cause severe diseases. These pathogens have evolved multiple intricate strategies to overcome the bactericidal activity of acids. In particular, recent studies have uncovered the central roles of two periplasmic chaperones, HdeA and HdeB, in protecting enteric bacteria from extremely acidic conditions. Here, we review recent advances in the understanding of the acid resistance mechanisms of Gram-negative bacteria and focus on the mechanisms of HdeA and HdeB in preventing acid-induced protein aggregation and facilitating protein refolding following pH neutralization. [ABSTRACT FROM AUTHOR]

Background & Aims: The roles of intestinal Toll-like receptors (TLR) in the pathogenesis of colitis are not known. TLR2 and TLR4 appear to protect against dextran sodium sulfate–induced colitis by promoting mucosal integrity, but it is not clear whether this method of protection occurs in other models of colitis. We investigated the roles of TLR2 and TLR4 and the cell types that express these receptors during infectious colitis. Methods: We generated chimeric mice with TLR2 −/− or TLR4 −/− bone marrow and infected them with the bacterial pathogen Citrobacter rodentium. We assessed their susceptibility to colitis and the mechanisms of TLR-mediated mucosal integrity. Results: TLR2-expressing tissue resident cells prevented lethal colitis, whereas TLR4-dependent inflammatory responses of hematopoietic cells mediated intestinal damage. TLR2 expression protected against intestinal damage by maintaining epithelial barrier function and inducing expression of interleukin (IL)-11 from tissue resident cells in the muscularis mucosae, concurrent with epithelial activation of the transcription factor STAT3. Addition of exogenous IL-11 protected against the lethal colitis in TLR2-deficient mice via STAT3 activation in intestinal epithelial cells. Conclusions: TLR2-dependent cytoprotective responses from tissue resident cells maintain mucosal integrity against the ultimately lethal TLR4-dependent inflammatory responses of hematopoietic cells. Whereas TLR2 protects against various noxious agents, the role of TLR4 during colitis can be either protective or damaging, depending on the stimulus. Therefore, therapeutics that reduce innate immunity (TLR2 signaling in particular) may not be beneficial to patients with colitis; they could worsen symptoms. Therapies that stimulate cytoprotective responses, like IL-11, could have benefits for patients with colitis. [ABSTRACT FROM AUTHOR]

Abstract: We evaluated the effect of using farmyard manure (FYM) in combination with four weed control techniques on the hygienic quality of lettuce. Treatments with six replications included the application of fresh FYM on the soil combined with hand-hoeing (assumed high-risk) and fresh FYM incorporation combined with plastic mulch (assumed low risk). The experiment was repeated twice per season over two years at Bonn University, Germany. The amounts of enteric bacteria in all treatments were within the acceptable limits. Enterococcus was detected in the majority of the samples in concentrations up to 3.7log10 CFU/g. The Escherichia coli contents of lettuce ranged between n.d. and 103 CFU/g. There was no consistent effect suggesting a specific risk linked to one of the experimental treatments. We conclude that weeding techniques did not increase the risk of exposure to E. coli when FYM is used for fertility in organic production systems. [Copyright &y& Elsevier]

Abstract: This study was carried out in order to quantify enteric bacteria and identify the presence of Salmonella spp., Escherichia coli, Clostridium perfringens and Erysipelothix rhusiopathiae in the liquid fraction of excreta generated from a small scale swine farm by means of a primary treatment system, consisting of the separation of solids and the sedimentation of liquids. Samples were collected at the following stages of the treatment: collection basin (CB), liquid obtained from a solids separator (SLF) and liquid from the sedimentation basin (SB). In each sample, enteric bacteria (cfu/g wet weight) and E. coli were quantified, Salmonella spp. was isolated and typified, and C. perfringens, and E. rhusiopathiae were isolated. No significant differences (p >0.05) were found in the enteric bacteria and E. coli population levels at any treatment stage. S. choleraesuis was found in 20% of CB samples analyzed, 40% of SLF samples and 30% of SB samples. C. perfringens was isolated from SLF and SB. E. rhusiopathiae was not isolated (below the minimum detection limit). Results suggest that primary treatment does not reduce the amount of enteric bacteria, or eliminate Salmonella spp., E. coli and C. perfringens. Therefore, it is necessary to apply additional treatments to allow safe use of the liquid obtained in the farm. [Copyright &y& Elsevier]

Abstract: The hygienic quality of head lettuce (Lactuca sativa L.) was investigated after different fertilizer treatments (fresh farmyard manure, composted farmyard manure, stinging nettle extract and calcium ammonium nitrate) in a 2-year field experiment with two trials per year, respectively. For assessment of the hygienic quality the total aerobic bacterial counts, Enterobacteriaceae, coliform bacteria, Escherichia coli and Salmonella were investigated in soil, fertilizer and lettuce samples. Plants were washed with running tap water before analysis. The total aerobic bacterial count, as well as the levels of Enterobacteriaceae and coliform bacteria tended to be slightly higher (not significant) after organic compared to mineral fertilization. No Salmonella was detected in any soil, fertilizer or lettuce sample, while E. coli was randomly detected in low concentrations independent from fertilizer treatment. No higher risk of bacterial contamination due to the use of organic fertilizers was indicated. [Copyright &y& Elsevier]

Summary: The types of selective pressure operating on the outer membrane protein C (ompC) of Enterobacter aerogenes strains, the causative agent for nosocomial infections, and Salmonella sp., the hazardous pathogen are investigated using the maximum likelihood-based codon substitution models. Although the rate of amino acid replacement to the silent substitution (ω) across the entire codon sites of ompC of E. aerogenes (ω=0.3194) and Salmonella sp. (ω=0.2047) indicate that the gene is subjected to purifying selection (i.e. ω<1), approximately 3.7% of ompC codon sites in E. aerogenes (ω=21.52) are under the influence of positive Darwinian selection (i.e. ω>1). Such contrast in the intensity of selective pressures in both pathogens could be associated with the differential response to the adverse environmental changes. In E. aerogenes, majority of the positively selected sites are located in the hypervariable cell-surface-exposed domains whereas the trans-membrane domains are functionally highly constrained. [Copyright &y& Elsevier]

The bacterial pathogens Shigella, Salmonella, Campylobacter, and shiga toxin-producing E. coli (STEC) were recently found to be associated with Cladophora growing in southern Lake Michigan. Preliminary results indicated that the Salmonella strains associated with Cladophora were genetically identical to each other. However, because of the small sample size (n =37 isolates) and a lack of information on spatial–temporal relationships, the nature of the association between Cladophora and Salmonella remained speculative. In this study, we investigated the population structure and genetic relatedness of a large number of Cladophora-borne Salmonella isolates from Lake Michigan (n =133), as well as those isolated from stream and lake water (n =31), aquatic plants (n =8), and beach sands and sediments (n =8) from adjacent watersheds. Salmonella isolates were collected during 2005–2007 between May and August from Lake Michigan beachsheds in Wisconsin, Illinois, and Indiana. The genetic relatedness of Salmonella isolates was examined by using the horizontal, fluorophore-enhanced rep-PCR (HFERP) DNA fingerprinting technique. While the Salmonella isolates associated with Cladophora exhibited a high degree of genetic relatedness (≥92% similarity), the isolates were not all genetically identical. Spatial and temporal relationships were evident in the populations examined, with tight clustering of the isolates both by year and location. These findings suggest that the relationship between Salmonella and Cladophora is likely casual and is related to input sources (e.g. wastewater, runoff, birds) and the predominant Salmonella genotype surviving in the environment during a given season. Our studies indicate that Cladophora is likely an important reservoir for Salmonella and other enteric bacterial pathogens in Lake Michigan beachsheds, which in turn may influence nearshore water quality. [Copyright &y& Elsevier]

Here we show that Preyssler-type polyoxotungstates (Preyssler-type POTs, [NaP 5 W 30 O 110 ]−14) complexed with peptides can prevent the dysbiotic expansion of anaerobic bacteria of the Enterobacteriaceae family. In a dextran sulfate sodium (DSS)-induced colitis model, symptom remission of C57BL/6 J mice with colitis is achieved by orally treated with POT complexes. Ten days of daily administration of POT complexes reduces 5% body weight loss and the mRNA levels of proinflammatory markers (77% reduction for Il6 , 73% reduction for Tnf , 91% reduction for Cxcl1) in the caecum and proximal colon. Bacterial population analysis reveals that these Enterobacteriaceae population in the caecal content decline by one order of magnitude after administration of POT complexes. POT complexes exert anti-inflammatory effects indirectly on the host immune system by inhibition of malignant expansion of anaerobic Enterobacteriaceae during gut inflammation. Furthermore, POTs show negligible effect on bacterial growth in vitro, healthy mice and their microbiota composition under homeostatic conditions. Rationally designed POT complexes will provide distinctive approach to improve enteric bacteria dysbiosis-associated gut inflammation by balancing bacterial communities. [Display omitted] • Polyoxotungstate (POT)-based complexes ameliorate bacteria dysbiosis in mice. • POT complexes reduce body weight loss caused by colitis. • POT complexes indirectly lower the expression of proinflammatory markers. • Peptides enhance the biological function of POT complexes. • POT complexes show no detectable [ABSTRACT FROM AUTHOR]

Abstract: Much has been learned in recent years about the mechanisms by which breastfeeding improves child health and survival. However, there has been little progress in using these insights to improve pediatric care. Factors that are important for protecting the breast fed infant might be expected to decrease the adverse effects of weaning on diarrhea, growth, and development. Lactoferrin, an iron-binding protein with multiple physiological functions (anti-microbial, anti-inflammatory, and immunomodulatory), is one of the most important proteins present in mammalian milk. Protection against gastroenteritis is the most likely biologically relevant activity of lactoferrin. Multiple in vitro and animal studies have shown a protective effect of lactoferrin on infections with enteric microorganisms, including rotavirus, Giardia, Shigella, Salmonella and the diarrheagenic Escherichia coli. Lactoferrin has two major effects on enteric pathogens: it inhibits growth and it impairs function of surface expressed virulence factors thereby decreasing their ability to adhere or to invade mammalian cells. Thus, lactoferrin may protect infants from gastrointestinal infection by preventing the attachment by enteropathogens in the gut. Recently several clinical trials in children have started to address this issue. Whether lactoferrin can prevent a significant portion of diarrheal disease remains to be determined. [Copyright &y& Elsevier]

Abstract: Feces contain intestinal bacteria and exfoliated epithelial cells that may provide useful information concerning gastrointestinal tract health. Intestinal bacteria that synthesize or metabolize potential carcinogens and produce anti-tumorigenic products may have relevance to colorectal cancer, the second most common cause of cancer deaths in the USA. To facilitate epidemiological studies relating bacterial and epithelial cell DNA and RNA markers, preservative/extraction methods suitable for self-collection and shipping of fecal samples at room temperature were tested. Purification and PCR amplification of fecal DNA were compared after preservation of stool samples in RNAlater (R) or Paxgene (P), or after drying over silica gel (S) or on Whatman FTA cards (W). Comparisons were made to samples frozen in liquid nitrogen (N2). DNA purification methods included Whatman (accompanying FTA cards), Mo-Bio Fecal (MB), Qiagen Stool (QS), and others. Extraction methods were compared for amount of DNA extracted, DNA amplifiable in a real-time SYBR-Green quantitative PCR format, and the presence of PCR inhibitors. DNA can be extracted after room temperature storage for five days from W, R, S and P, and from N2 frozen samples. High amounts of total DNA and PCR-amplifiable Bacteroides spp. DNA (34%±9% of total DNA) with relatively little PCR inhibition were especially obtained with QS extraction applied to R preserved samples (method QS-R). DNA for human reduced folate carrier (SLC19A1) genomic sequence was also detected in 90% of the QS-R extracts. Thus, fecal DNA is well preserved by methods suitable for self-collection that may be useful in future molecular epidemiological studies of intestinal bacteria and human cancer markers. [Copyright &y& Elsevier]

Abstract: The objectives of this study were to estimate the prevalence of the enteric microbes: Escherichia coli, Salmonella, Campylobacter and Enterococcus spp., in plant-protein-based animal feed products and milk replacer and to identify risk factors associated with contamination by these bacteria. A cross-sectional survey of 158 plant-derived feed and milk replacer samples was conducted using eight animal feed stores in Northern Virginia and Maryland from January 2002 to September 2002. Overall, all samples were negative for Campylobacter; one sample (0.6%) was positive for Salmonella; nine samples (5.7%) were positive for E. coli and 80 samples (50.6%) were positive for Enterococcus. Positive samples included: whole maize, cracked peanut, cotton seed, mixed grain horse feed, and milk replacer. Samples collected during the month of January (winter) had a lower prevalence of contamination with enteric bacteria than samples collected in August and September (summer/autumn). Samples collected in January 2002 were negative for both E. coli and Salmonella. Samples collected in August and September 2002 included one Salmonella positive, and nine E. coli positive. Animal feed purchased during August and September had a 38-fold increase (95% CI: 15.60–95.16) in the risk of contamination by Enterococcus than those samples purchased during January and February of that same year (P<0.001). Enterococcus positive samples were eight times more likely to also be E. coli positive than Enterococcus negative samples (95% CI: 1.04–70.12). Non-pelleted feed was 13 times more likely to be contaminated with Enterococcus than pelleted feed (95% CI: 3.02–59.84). [Copyright &y& Elsevier]

Abstract: Physiological evidence from our laboratory indicates that Amt/Mep proteins are gas channels for NH3, the first biological gas channels to be described. This view has now been confirmed by structural evidence and is displacing the previous belief that Amt/Mep proteins were active transporters for the NH4 + ion. Still disputed is the physiological substrate for Rh proteins, the only known homologues of Amt/Mep proteins. Many think they are mammalian ammonium (NH4 + or NH3) transporters. Following Monod''s famous dictum, “Anything found to be true of E. coli must also be true of elephants” [Perspect. Biol. Med. 47(1) (2004) 47], we explored the substrate for Rh proteins in the unicellular green alga Chlamydomonas reinhardtii. C. reinhardtii is one of the simplest organisms to have Rh proteins and it also has Amt proteins. Physiological studies in this microbe indicate that the substrate for Rh proteins is CO2 and confirm that the substrate for Amt proteins is NH3. Both are readily hydrated gases. Knowing that transport of CO2 is the ancestral function of Rh proteins supports the inference from hematological research that a newly evolving role of the human Rh30 proteins, RhCcEe and RhD, is to help maintain the flexible, flattened shape of the red cell. [Copyright &y& Elsevier]

Abstract: We measured Escherichia coli, Enterococcus spp. and fecal coliform numbers in soil and on fresh potato skins after addition of solid dairy manure and dairy compost with and without alum (Al2(SO4)3) treatment 1, 7, 14, 28, 179 and 297days after application. The addition of dairy compost or solid dairy manure at rates to meet crop phosphorus uptake did not consistently increase E. coli and Enterococcus spp. and fecal coliform bacteria in the soil. We did not detect E. coli in any soil sample after the first sampling day. Seven, 14, 28, 179 and 297days after solid dairy waste and compost and alum were applied to soil, alum did not consistently affect Enterococcus spp. and fecal coliform bacteria in the soil. We did not detect E. coli in any soil, fresh potato skin or potato wash-water at 214days after dairy manure or compost application regardless of alum treatment. Dairy compost or solid dairy manure application to soil at rates to meet crop phosphorus uptake did not consistently increase Enterococcus spp. and fecal coliform numbers in bulk soil. Solid dairy manure application to soil at rates to meet crop phosphorus uptake, increased Enterococcus spp. and fecal coliform numbers in potato rhizosphere soil. However, fresh potato skins had higher Enterococcus spp. and fecal coliform numbers when solid dairy manure was added to soil compared to compost, N and P inorganic fertilizer and N fertilizer treatments. We did not find any E. coli, Enterococcus or total coliform bacteria on the exterior of the tuber, within the peel or within a whole baked potato after microwave cooking for 5min. [Copyright &y& Elsevier]

Abstract: The Formosan subterranean termite, Coptotermes formosanus Shiraki, is an aggressive, invasive termite species that has caused billions of dollars of damage across the United States for the past 50 years. Termites depend on intestinal microorganisms for cellulose digestion. Symbiotic microorganisms in the termite gut play key physiological functions such as cellulose and hemicellulose digestion, acetogenesis, hydrogenesis, methanogenesis, sulfate reduction, and nitrogen fixation. Additionally, intestinal microbes create suitable conditions for symbiotic protozoans through the production of nutrients and the maintenance of the pH and the anaerobic conditions in the gut. Although extensive research has been done on the symbiotic relationship of these termites and the microbes found in its gut, there is little information available on the role of facultative anaerobes in the gut. We isolated four enteric bacteria from the hindgut of Formosan subterranean termite, C. formosanus. All isolates were facultative anaerobes and G−. The isolates were identified as Serratia marcescens, Enterobacter aerogens, Enterobacter cloacae, and Citrobacter farmeri by using BIOLOG assay and fatty acid methyl ester analysis (FAME). Each isolate was characterized using sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis and biochemical study. This is the first report on the presence of facultative microbes in termite gut. Results of this first study on facultative microbes in the termite gut indicate that the role of facultative organisms in the Formosan termite gut may be to scavenge oxygen and create anaerobic conditions for the anaerobic microorganisms, which are essential for digestion of cellulose consumed by the termite. [Copyright &y& Elsevier]

Abstract: Recreational water quality at beaches in California and elsewhere is often poor near the outlets of rivers, estuaries, and lagoons. This condition has prompted interest in the role of wetlands in modulating surface water concentrations of fecal indicator bacteria (FIB), the basis of water quality standards internationally. A model was developed and applied to predict the dry-weather tidal cycling of FIB in Talbert Marsh, an estuarine, intertidal wetland in Huntington Beach, California, in response to loads from urban runoff, bird feces, and resuspended sediments. The model predicts the advection, dispersion and die-off of total coliform, Escherichia coli, and enterococci using a depth-integrated formulation. We find that urban runoff and resuspension of contaminated wetland sediments are responsible for surface water concentrations of FIB in the wetland. Model predictions show that urban runoff controls surface water concentrations at inland sites and sediment resuspension controls surface water concentrations near the mouth. Direct wash-off of bird feces into the surface water is not a significant contributor, although bird feces can contribute to the sediment bacteria load. The key parameters needed to accurately predict FIB concentrations, using a validated hydrodynamic model, are: the load due to urban runoff, sediment erodibility parameters, and sediment concentrations and surface water die-off rates of enteric bacteria. In the present study, literature values for sediment erodibility and water column die-off rates are used and average concentrations of FIB are predicted within 1/2 log unit of measurements. Total coliform are predicted more accurately than E. coli or enterococci, both in terms of magnitude and tidal variability. Since wetland-dependent animals are natural sources of FIB, and FIB survive for long periods of time and may multiply in wetland sediments, these results highlight limitations of FIB as indicators of human fecal pollution in and near wetlands. [Copyright &y& Elsevier]

Stool specimens were collected from 180 patients belonging to a population of recently settled Bedouins in Jordan who presented with acute or persistent diarrhoea and other symptoms, and from 100 non-diarrhoeal controls. All samples were examined for parasites and bacterial pathogens by culture and PCR. Bacterial isolates were tested for their susceptibility to common antimicrobial agents. Pathogens and potential enteropathogens were identified from 140 (77.8%) of the patients, with more than one pathogen being recovered from 67 (37.2%) patients. Potentially pathogenic parasites were observed in 90 (50%) patients; those that were associated significantly with diarrhoea were Giardia lamblia, Blastocystis hominis, Cryptosporidium spp., Entamoeba histolytica and Cyclospora cayetanensis. Pathogenic bacteria were isolated from 72 (40%) patients, and, of these, 62.5% were resistant to at least one antibiotic, and 30.6% of these were multiresistant. Diarrhoeagenic Escherichia coli strains were found in 14.3% of the patients and 2.9% of the control subjects (not statistically significant). The most common enteropathogenic bacteria found were Shigella spp., Campylobacter jejuni and Yersinia enterocolitica. Unusual bacterial species were the predominant organisms recovered in a few cases and could represent a possible cause of diarrhoea. Overall, there was a high endemicity of diarrhoeal disease in the area studied. Risk factors that correlated significantly with contracting diarrhoea were socio-economic status, education, use of unchlorinated well or tank water, and a low level of personal hygiene. [ABSTRACT FROM AUTHOR]

Senescence-accelerated mouse (SAM) P1/Yit mouse showed spontaneous ileitis and cecitis when reared under specific-pathogen-free (SPF) conditions. Intestinal lesions in the SAMP1/Yit strain exhibit discontinuous and transmural inflammation accompanied by numerous inflammatory infiltrates. Granulomas were often located in peyer''s patches. These characteristics resembled the features of Crohn''s disease (CD). Intravenous injection of gut-associated-lymphoid-tissue (GALT)-derived CD4+ αβ T cells isolated from SAMP1/Yit mice into SPF scid mice induced ileitis and cecitis in recipient''s scid mice. However, the intestinal inflammation was absent in germfree (GF) SAMP1/Yit mice. Here we demonstrated the specific interaction between GALT-derived CD4+ αβ T cells and enteric bacteria in the immunopathogenesis of the Crohn''s disease-like inflammatory bowel disease (IBD) in SAMP1/Yit mice. [Copyright &y& Elsevier]

The survival of human enteric bacteria in the aquatic environment has attracted much interest in view of its public health significance. Untreated sewage has been released from Dumont d'Urville station, Antarctica, into the Southern Ocean for several years. The spatial distribution of faecal bacteria indicators was investigated in summer ice-free seawater near the French Base station of the Adelie land area. Acomplementary seasonal survey of the occurrence of faecal coliform bacteria was conducted in seawater under the winter sea ice in a specific station. Relatively high bacterial densities (maximum 103 CFU 100 ml-1) were found in seawater surrounding the sewage outfall. However, the contamination decreased rapidly with increasing distance from the outfall. In all samples collected further than 2 km, the bacterial indicators were absent or present in very small numbers. Faecal coliforms were not detected in samples collected atpristine sites. Despite these relatively low contamination levels, faecal bacteria were always detected in the vicinity of the sewage outfall during the seasonal survey conducted in ice and under-ice seawater. [ABSTRACT FROM AUTHOR]