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Se evaluó el desarrollo y producción de la col (Brassica oleracea var. Royal vantage) en invernadero, bajo diferentes presiones osmóticas de la solución nutritiva Steiner y biofertlizada con consorcios bacterianos. Se estableció un diseño factorial 4 × 3, donde los factores fueron cuatro niveles de presión osmótica (0.18, 0.36, 0.54 atm y un testigo sin solución nutritiva), y dos consorcios bacterianos: Azospirillum brasiliense + Acinetobacter calcoaceticus (AA) y Raoultella terrigena + Chromobacterium violaceum (RC), y un testigo sin inocular. Se establecieron seis repeticiones por cada tratamiento. Las semillas inoculadas con el consorcio AA presentaron el mayor porcentaje de emergencia (100%), así como la tasa de emergencia más alta (20.5), en comparación con consorcio RC y las plantas no inoculadas. La inoculación con el consorcio AA y la presión osmótica de 0.54 atm produjeron plantas más altas (60-65%), y un tallo con mayor diámetro (35-46%). El peso de la biomasa fresca y la acumulación de materia seca se duplicaron en las plantas inoculadas con respecto a las no inoculadas. Se observó mayor concentración de K en plantas inoculadas con AA y RC (20-35% y 25-45%, respectivamente) respecto a las plantas no inoculadas. La concentración de nitratos en las plantas se incrementó entre 200-350% y 60-230% con la inoculación de los consorcios AA y RC, respectivamente. La concentración de P se incrementó entre 200-500% con el consorcio AA y entre 100-400% con el consorcio RC. La inoculación con los consorcios AA y RC, a presión osmótica de 0.54 atm, indujo el mayor desarrollo de las cabezas de la col (clasif icadas como 5 y 4, respectivamente). Se concluye que la col, bajo fertilización mineral moderada en invernadero, responde favorablemente a la inoculación de bacterias promotoras de crecimiento vegetal.

Endophytic nitrogen-fixing (diazotrophic) bacteria are essential members of the microbiome of switchgrass (Panicum virgatum), considered to be an important commodity crop in bioenergy production. While endophytic diazotrophs are known to provide fixed atmospheric nitrogen to their host plant, there are many other plant growth-promoting (PGP) capabilities of these organisms to be demonstrated. The diversity of PGP traits across different taxa of switchgrass-colonizing endophytes is understudied, yet critical for understanding endophytic function and improving cultivation methods of important commodity crops. Here, we present the isolation and characterization of three diazotrophic endophytes: Azospirillum agricola R1C, Klebsiella variicola F10Cl, and Raoultella terrigena R1Gly. Strains R1C and F10Cl were isolated from switchgrass and strain R1Gly, while isolated from tobacco, is demonstrated herein to colonize switchgrass. Each strain exhibited highly diverse genomic and phenotypic PGP capabilities. Strain F10Cl and R1Gly demonstrated the highest functional similarity, suggesting that, while endophyte community structure may vary widely based on host species, differences in functional diversity are not a clearly delineated. The results of this study advance our understanding of diazotrophic endophyte diversity, which will allow us to design robust strategies to improve cultivation methods of many economically important commodity crops.

Raoultella terrigena is a rarely found opportunistic pathogen that can cause healthcare‐associated infections with high mortality. It is important to differentiate it from Klebsiella species.

The objective of this work was to isolate and identify of 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase producing endophytic bacteria from root of local agricultural plantation by using 16S rRNA gene as genetic marker. Twelve root samples were collected from local agricultural plantation in Java area. After surface sterilization, each root sample was inoculated in nutrient agar media and the grown colonies were further purified and tested for the ability to grow in N-free minimal medium containing AIB as a sole of nitrogen source. The selected colonies were further tested for their ACC deaminase activity by measuring the rate of conversion of ACC into α-ketobutyrate. From this work, 12 bacterial strains that exhibited the ACC deaminase activity by 123.75 to 1461.44 nmol α-ketobutyrate/mg/hour were successfully isolated. Based on the 16SrRNA gene sequences, those bacterial isolates were identified as Sphingobacterium multivorum BK1, Bacillus mycoides CB2, Pantoea dispersa CK4, Pantoea agglomerans KD6.2, Enterobacter ludwigii KW3, Bacillus aryabhattai TW7, Pseudomonas monteilii KS12, Pseudomonas plecoglossicida KS16.2, Pseudomonas putida PIR3C, Stenotrophomonas maltophilia PIR5, Lysinibacillus pakistanensis PIC5, and Raoultella terrigena PCM8. Pseudomonas putida PIR3C and Pseudomonas monteilii KS12 showed promising ACC deaminase activity and therefore it could be as a good candidate for further application in plant growth promoting in stress conditions.

Guanidine is sensed by at least four different classes of riboswitches that are widespread in bacteria. However, only very few insights into physiological roles of guanidine exist. Genes predominantly regulated by guanidine riboswitches are Gdx transporters exporting the compound from the bacterial cell. In addition, urea/guanidine carboxylases and associated hydrolases and ABC transporters are often found combined in guanidine‐inducible operons. We noted that the associated ABC transporters are configured to function as importers, challenging the current view that riboswitches solely control the detoxification of guanidine in bacteria. We demonstrate that the carboxylase pathway enables utilization of guanidine as sole nitrogen source. We isolated three enterobacteria (Raultella terrigena,Klebsiella michiganensis, and Erwinia rhapontici) that utilize guanidine efficiently as N‐source. Proteome analyses show that the expression of a carboxylase, associated hydrolases and transport genes is strongly induced by guanidine. Finding two urea/guanidine carboxylase enzymes in E. rhapontici, we demonstrate that the riboswitch‐controlled carboxylase displays specificity towards guanidine whereas the other enzyme prefers urea. We characterize the distribution of riboswitch‐associated carboxylases and Gdx exporters in bacterial habitats by analysing available metagenome data. The findings represent a paradigm shift from riboswitch‐controlled detoxification of guanidine to the uptake and assimilation of this enigmatic nitrogen‐rich compound. published

Objectives:Raoultella terrigena (formerly Klebsiella terrigena) is an environmental gram-negative rod. It may cause infections in humans, especially in the elderly and immunosuppressed patients. Moreover, this organism tends to be multi-drug resistant, limiting treatment options. Evidence on clinical presentation and outcomes of this infection is limited. We conducted this study to see its various clinical features, available treatment options, and associated clinical impacts of the R.terrigena infections. Methodology:We conducted a cross-sectional study on all adult patients with clinical specimens positive for Raoultella terrigena at a 700-bedded tertiary care hospital in Karachi, Pakistan, between January 2013 to December 2018. Results:There were 58 patients with R.terrigena in different cultures specimens identified. Amongst them n=12 (22.6%) were colonizers. The median age was 61.5 years (IQR=28), and most were male (60.9%). The most common infection site was the respiratory tract in 28.3%, followed by urinary tract infections, 26%, and central line-associated infections at 26.1%. Amongst infected cases, 37% were in septic shock, and of which 76.5% required vasopressors. 45.7% had respiratory failure requiring non-invasive ventilation in 47.6%, and mechanical ventilation in 52.4%. The previous history of multidrug-resistant organisms was present in 67.4% of patients and the history of prior antibiotics use within the last six months was present in 78.3%. 91.3% of isolates were resistant to piperacillin-tazobactam and meropenem, 65.2% were resistant to colistemethate. Eight patients lost to follow up. The majority of patients treated with combination therapy (n=31, 81.6%) and meropenem plus colistemethate was the most commonly used combination (n=11, 44%). The overall mortality rate was 44.7%. Conclusion: R.terrigena is a highly drug-resistant organism with a high mortality rate and causes hospital-acquired respiratory tract infections in most patients.

Biodiesel-derived glycerol was biologically converted to 2,3-butanediol, an organic compound with multiple industrial applications. Recent studies showed that Raoultella terrigena CECT 4519 is an effective biocatalyst for the bioprocess under conventional growing conditions. In the present work, a novel biocatalyst composed by R. terrigena resting cells was evaluated for the first time. Fluid dynamic conditions has been optimized to maximize 2,3-butanediol production in terms of titre, yield, and selectivity. Regarding the effect of initial glycerol concentration in batch runs, no substrate inhibition was detected in the studied conditions (concentrations between 45 and 250 g/L were used). Employing pure glycerol as carbon source, 82.0 g/L 2,3-butanediol titre was achieved, whereas 76.5 g/L were reached using raw glycerol. These numbers involve an achieved yield respect to maximal theoretic yield of 79% and 77%, respectively. A successful kinetic modelling of the bioprocess was developed and it is able to describe both the evolution of concentrations of relevant components with time and the rates calculated at experimental time values. Estimated specific 2,3-butanediol production rate was 0.034 g2,3-BDO/gX⋅h, while the estimated empirical pseudo-stoichiometric coefficient glycerol/2,3-butanediol was 2.52 gGly/g2,3-BDO. The obtained results showed that R. terrigena resting cells is a promising biocatalyst, which provides new opportunities for developing and scaling-up glycerol biorefineries. post-print 856 KB

The aim of this study was to determine the possibility of applying psychrophilic bacteria for hydrogen production in cheese whey and glucose biofermentation process with initial organic load reached 1 g COD/L. Depending on the experimental variant, analyses were carried out for psychrophilic bacteria representing Proteobacteria- Rahnella aquatilis, Raoutella terrigena and Firmicutes - Carnobacterium maltaromaticum, Clostridium algidixylanolyticum. Tested microorganisms were isolated from underground water and from demersal lake water. Regardless of the organic substrate used in experiments, the most effective rate of hydrogen production was obtained for Rahnella aquatilis and Clostridium algidixylanolyticum strains. The significantly lower effectiveness of H2 production was observed in the process of glucose fermentation by strains Raoultella terrigena and Carnobacterium maltaromaticum. The concentration of H2 in biogas ranged from 32.61% to 43.21%. The quantity of H2 production during cheese whey fermentation ranged from 20.1 to 58.1 mL H2/g CODfed, while during glucose fermentation ranged from 16.3 to 52.1 mL H2/g CODfed. Taking into consideration the quantity of biogas and its H2 concentration obtained from various organic substrates during fermentation in psychrophilic conditions, the results of this study may be considered promising for the perspective application.

BACKGROUND The fluid dynamic conditions play a key role in the development and scaling-up of bioprocesses. In aerobic cultures, oxygen is an essential substrate for microbial growth, production and culture maintenance; an effective gas–liquid transfer must be achieved. Changes in fluid dynamics due to stirrer speed can affect the culture negatively, causing hydrodynamic stress (increasing shear stress) or oxidative stress (by an increase of available oxygen in the liquid phase). RESULTS Under oxygen-limiting conditions, specific growth rate increases with stirrer speed, and several fermentation products were specifically released to the culture medium. BD production increased with stirrer speed, reaching a maximum at 400 rpm. When the agitation was increased over 550 rpm, the metabolic flux was mainly routed to increase the cell growth. Negative effects of fluid dynamic conditions on biomass production were observed at 1900 and 2000 rpm. Cellular response to shear stress conditions was also shown in the large increase with time of the broth viscosity. CONCLUSIONS R. terrigena is able to adapt the carbon metabolic flux to the availability of oxygen, producing fermentation products, alcohols or directing microbial growth. Moreover, cells can withstand aggressive agitation conditions (until 1600 rpm).

This study presents an effective technology for the olive processing industry to remediate olive washing water. A 14.5-L enclosed tubular photobioreactor was inoculated with a stable microalgal-bacterial consortium obtained by screening strains well adapted to olive washing water. The capacity of an enclosed tubular photobioreactor to remove toxic compounds was evaluated under photosynthesis conditions and without any external supply of oxygen. The results showed that the dominant green microalgae Scenedesmus obliquus, Chlorella vulgaris and the cyanobacteria Anabaena sp. and bacteria present in olive washing water (i.e. Pantoea agglomerans and Raoultella terrigena) formed a synergistic association that was resistant to toxic pollutants present in the effluent and during the initial biodegradation process, which resulted in the breakdown of the pollutant. Total phenolic compounds, COD, BOD5, turbidity and colour removals of 90.3 ± 11.4, 80.7 ± 9.7, 97.8 ± 12.7, 82.9 ± 8.4 and 83.3 ± 10.4 %, respectively, were recorded in the photobioreactor at 3 days of hydraulic retention time.

Raoultella terrigena is a bacterial species associated with soil and aquatic environments; however, sporadic cases of opportunistic disease in humans have been reported. Here, we report the first two complete genome sequences from clinical strains isolated from human sources that have been deposited in the National Collection of Type Cultures (NCTC).

30 p.-3 fig., Bioconversion of biodiesel-derived glycerol into 2,3-butanediol has received recently much attention due to its increasing surplus and its multiple uses in industry as bulk chemical. The influence of initial glycerol concentration on 2,3-butanediol production in batch runs has been studied. A concentration higher than 140 g/L produces an inhibitory effect on the final 2,3-butanediol concentration and its production rate. In batch mode, the highest yield respect to the theoretical maximum yield (71%) was reached employing 140 g/L as initial concentration 140 g/L. Based on these results, a high 2,3-butanediol production has been achieved through a fed-batch strategy. The reached 2,3-butanediol concentration was 90.5 g/L from pure glycerol and 80.5 g/L from raw glycerol. The 2,3-butanediol yield respect to the theoretical maximum yield was also improved through the fed-batch operation (90%). To date, this concentration is the highest produced amount employing as biocatalyst a non-pathogenic bacterium (level 1)., This work was supported by the Ministerio de Economía, Industria y Competitividad -MINECO-, Gobierno de España, under contract EUI2008-03600 and CTQ2010-11765-E.

This study examined the effects of pH, temperature, NaCl concentration and heat resistances of Raoultella spp. isolated from a seafood processing plant in Thailand. The ability to resist to cleaning and sanitizing agents were also investigated. The effect of growth medium (Tryptic Soy Broth) adjusted to various pHs (3, 4, 5, 6, 7, 8, 9, 10) revealed Raoultella ornithinolytica and R. terrigena were able to grow well at pH 6–9, slow growth at 4 and 10 but not at strong acidic pH 3. Growth at different temperature was done (4, 15, 20, 37, 40°C) and found optimum growth was ranged at 15–37°C. Sodium chloride concentrations test was at 1%, 1.5%, 2.5%, 3.5%, 4.5%, 5.5% and 6.5% revealed the optimal growth at 1–4.5% NaCl. D-values of both species gave similar result as 0.66–0.79 min at 57°C, with Z-value 4.2–4.5°C. When cell suspension and biofilm were exposed to cleaning agent (sodium hydroxide, lauryl dimethylamine oxide, and sodium hypochlorite), and three sanitizers, namely, sodium hypochlorite (NaClO), hydrogen peroxide (H2O2), and ozonated water. NaClO was able to eliminate single biofilm of Raoultella spp. at 50 ppm in 5 min while ozone had less efficacy to kill biofilm cells. H2O2 at 1% and 2% succeeded to eliminate biofilm. This finding properties of Raoultella spp. will be useful for designing strategies to prevent and control contamination these species regarding seafood plant sanitation.

Background Raoultella terrigena (formerly Klebsiella terrigena) is an environmental gram-negative rod, occasionally causing infections in humans, especially in elderly, immunosuppressed patients. Moreover, this organism tends to be multi-drug resistant, limiting treatment options. Evidence on clinical presentation and outcomes of this infection is limited; we conducted a cross-sectional study to get a better insight into these infections. Methods We conducted a cross-sectional study on all adult patients with clinical specimen positive for Raoultella terrigena at a 700-bedded tertiary care hospital in Karachi, Pakistan, between January 2013 to December 2018. Results A total of 58 patients with R. terrigena were identified. The median age was 61.5 years, and the male to female ratio was (60.9% vs. 39.1%). The most common site of infection was respiratory tract 28.3%, followed by urinary tract infections 26%, and central line-associated infections 15.2%. In 12 patients 22.6%, R. terrigena was a colonizer. Amongst infected cases, 23.6% were in shock, and of which 18.1% required vasopressors. 29.2% had respiratory failure requiring non-invasive ventilation in 13.9%, and mechanical ventilation in 15.3%. The previous history of multidrug-resistant organisms was present in 67.4% cases and the history of prior antibiotics use within the last six months was present in 78.3%. 91.3% of isolates were resistant to piperacillin-tazobactam and meropenem, 65.2% were resistant to colistimethate. However, tigecycline susceptibility maintained in 30.4% checked in n=31, 67.4% and fosfomycin sensitivity in 15.2% cases, checked in n=29, 63% cases. Eight patients lost to follow up. Majority of patients were treated with combination therapy n=31, 81.6% and meropenem plus colistemethate was the most commonly used combination n=11, 44%. The overall mortality rate was 44.7%. Among all recorded co-morbid conditions, chronic kidney disease was strongly associated with mortality (p= .029), as also the use of vasopressors (p= .005).Persons who had high (greater or equal to three) Charlson comorbidity index had high mortality (p=0.002). Conclusion R.terrigena is a highly drug-resistant organism with high mortality rate, and causes hospital-acquired respiratory tract infections in majority of patients. Disclosures All Authors: No reported disclosures

Bioconversion of biodiesel-derived waste glycerol into high-value products is proposed as a solution to improve economic viability of biorefineries. Several microorganisms are able to metabolize glycerol into 2,3-butanediol (2,3-BD), a promising bulk chemical with wide applications: solvent, fuel additive, and feedstock for synthetic rubber production, among them. In the present work, a wide screening of microorganisms present both into the waste water treatment system in a biodiesel industry and in culture collections was carried out in order to evaluate their potential as new 2,3-BD producer biocatalysts. Two microorganisms for 2,3-BD production from glycerol as sole carbon source have been selected, namely Raoultella planticola CECT 843 and Raoultella terrigena CECT 4519. Raoultella strains belong to the non‐pathogenic bacteria class (biosafety level 1). This genus has not been previously described as biocatalyst for the studied process. The influence of operational temperature, organic acid addition, and yeast extract concentration on 2,3-BD yield and productivity have been studied through Taguchi design methodology as well as initial glycerol concentration. Based on these results, the feasibility of the process employing pure glycerol and different samples of raw glycerol has been demonstrated.

Export of the Escherichia coli serotype O9a O-antigenic polysaccharides (O-PS) involves an ATP-binding cassette (ABC) transporter. The process requires a non-reducing terminal residue, which is recognized by a carbohydrate-binding module (CBM) appended to the C terminus of the nucleotide-binding domain of the transporter. Here, we investigate the process in Klebsiella pneumoniae serotype O12 (and Raoultella terrigena ATCC 33257). The O12 polysaccharide is terminated at the non-reducing end by a β-linked 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo) residue. The O12 ABC transporter also binds its cognate O-PS via a CBM, and export is dependent on the presence of the terminal β-Kdo residue. The overall structural architecture of the O12 CBM resembles the O9a prototype, but they share only weak sequence similarity, and the putative binding pocket for the O12 glycan is different. Removal of the CBM abrogated O-PS transport, but export was restored when the CBM was expressed in trans with the mutant CBM-deficient ABC transporter. These results demonstrate that the CBM-mediated substrate-recognition mechanism is evolutionarily conserved and can operate with glycans of widely differing structures.

Lysogenic bacteriophages may encode enzymes that modify the structures of lipopolysaccharide O-antigen glycans, altering the structure of the bacteriophage receptor and resulting in serotype conversion. This can enhance virulence and has implications for antigenic diversity and vaccine development. Side chain glucosylation is a common modification strategy found in a number of bacterial species. To date, glucosylation has only been observed in O-antigens synthesized by Wzy-dependent pathways, one of the two most prevalent O-antigen synthesis systems. Here we exploited a heterologous system to study the glucosylation potential of a model O-antigen produced in an ATP-binding cassette (ABC) transporter-dependent system. Although O-antigen production is cryptic in Escherichia coli K-12, because of a mutation in the synthesis genes, it possesses a prophage glucosylation cluster, which modifies the GlcNAc residue in an α-l-Rha-(1→3)-d-GlcNAc motif found in the original O16 antigen. Raoultella terrigena ATCC 33257 produces an O-antigen possessing the same disaccharide motif, but its assembly uses an ABC transporter-dependent system. E. coli harboring the R. terrigena O-antigen biosynthesis genes produced an O-antigen displaying reduced reactivity toward antisera raised against the native R. terrigena repeat structure, indicative of an altered chemical structure. Structural determination using NMR revealed the addition of glucose side chains to the repeat units. O-antigen modification was dependent on a functional ABC transporter, consistent with modification in the periplasm, and was eliminated by deletion of the glucosylation genes from the E. coli chromosome, restoring native level antisera sensitivity and structure. There are therefore no intrinsic mechanistic barriers for bacteriophage-mediated O-antigen glucosylation in ABC transporter-dependent pathways.

2nd International Conference on Applied Sciences (ICAS), Ton Duc Thang Univ, Ho Chi Minh City, VIETNAM, MAY 24-25, 2018; International audience; Two bacteria, Enterobacter ludwigii Ez-185-17 and Raoultella terrigena Ez-555-6, isolated from root nodules of Medicago lupulina from the Chernobyl exclusion zone, were identified in a previous study and shown not to disturb plant growth. The main goal of this work is to elucidate the relationships between these bacteria and flax, in particular whether they display activities such as plant growth promoting bacteria (PGPB) properties or modulation hairy root development. In order to better understand their role in plants, some known PGPB properties were determined in comparison with several control bacteria. The influence of these bacteria on Linum usitatissimum growth under hydroponic conditions was also investigated. Our study shows that both bacteria belong to PGPB since they were able to increase considerably the root surface area of flax, especially Raoultella terrigena Ez-555-6. Significant IAA production and phosphate solubilization of Enterobacter ludwigii Ez-185-17 were highlighted, which enabled these biochemical PGPB properties to be correlated with their effects on flax growth. However, Raoultella terrigena Ez-555-6 did not express high biochemical activities, suggesting that other PGPB abilities should be studied in order to establish the link with flax growth improvement.

Background Chromosomal class A β-lactamases have been characterized in Raoultella ornithinolytica and Raoultella planticola. The purpose of this study was to characterize that of Raoultella terrigena. Materials and methods The blaTER-1 gene of R. terrigena strain ATCC33257T was cloned (pACter-1) and sequenced. It was then used to detect the bla gene of strains BM 85 01 095 and SB2796. The hypermutable Escherichia coli strain AB1157 mutS::Tn10 was transformed with pACter-1 and mutants growing on plates containing > 2 mg/L ceftazidime were studied. Notably, the impact of mutations only observed in the promoter region on β-lactam resistance was assessed by site-directed mutagenesis experiments. Results R. terrigena strains ATCC33257T and BM 85 01 095 had the same bla gene and deduced protein (TER-1) whereas there were 3 substitutions in those of strain SB2796 (TER-2). Class A β-lactamases TER showed 78%, 69.9% and 38.7% identity with PLA or ORN, TEM-1 and KOXY, respectively. Compared with TEM-1, TER-1 and TER-2 showed 2 particular substitutions, Leu75Pro and Glu240Asn demonstrated to be involved in the inherent β-lactam resistance profile of R. terrigena. TER-1 (pI of 7.6) had a high activity against penicillin G and a significantly low one against amoxicillin. Substitution G/T observed in the -35 region of the blaTER gene harbored by strains growing in the presence of ≥ 2 mg/L ceftazidime was shown to be responsible for this growth. Conclusion TER is a new class A β-lactamase belonging to functional group 2b.

Lipopolysaccharides (LPS) are essential outer membrane glycolipids in most gram-negative bacteria. Biosynthesis of the O-antigenic polysaccharide (OPS) component of LPS follows one of three widely distributed strategies, and similar processes are used to assemble other bacterial surface glycoconjugates. This study focuses on the ATP-binding cassette (ABC) transporter-dependent pathway, where glycans are completed on undecaprenyl diphosphate carriers at the cytosol:membrane interface, before export by the ABC transporter. We describe Raoultella terrigena WbbB, a prototype for a family of proteins that, remarkably, integrates several key activities in polysaccharide biosynthesis into a single polypeptide. WbbB contains three glycosyltransferase (GT) modules. Each of the GT102 and GT103 modules characterized here represents a previously unrecognized GT family. They form a polymerase, generating a polysaccharide of [4)-α-Rhap-(1→3)-β-GlcpNAc-(1→] repeat units. The polymer chain is terminated by a β-linked Kdo (3-deoxy-d-manno-oct-2-ulosonic acid) residue added by a third GT module belonging to the recently discovered GT99 family. The polymerase GT modules are separated from the GT99 chain terminator by a coiled-coil structure that forms a molecular ruler to determine product length. Different GT modules in the polymerase domains of other family members produce diversified OPS structures. These findings offer insight into glycan assembly mechanisms and the generation of antigenic diversity as well as potential tools for glycoengineering.

Aims To characterize the nematicidal endophytic bacteria (NEB) of Wasabia japonica (wasabi) and evaluated the control efficacies of promising NEB as well as fresh wasabi residue (FWR) against Meloidogyne incognita on tomato. Methods and Results By in vitro bioassay, 53 NEB strains showing nematicidal efficacies of >50% against J2 of M. incognita were isolated from wasabi. Basing on 16S rRNA gene sequences, these NEB were identified into 18 species of 11 genera. In greenhouse, incorporation of selected NEB culture or FWR into potted soil significantly reduced infection of M. incognita on tomato. Treating tomatoes with either FWR or NEB of Raoultella terrigena RN16 and Pseudomonas reinekei SN21 in the field yielded excellent control efficacies against M. incognita, especially the combinations of FWR with either R. terrigena RN16 or Ps. reinekei SN21 at doses of 50 g plus 100 ml per plant or more. Conclusions The results established that R. terrigena RN16 and Ps. reinekei SN21 applied separately or combined with FWR have the potential to provide bioprotection agents against M. incognita. Significance and Impact of the Study This study provides novel way for disease management using combination of endophyte and host residue.

The green shield bug, Palomena prasina (Hemiptera: Pentatomidae), is a pest of deciduous trees and shrubs throughout Turkey and is found in a large variety of habitats, including gardens. We investigated the facultative cultivable bacterial flora of 10 healthy and 5 dead green shield bugs, collected from the vicinity of Trabzon, Turkey, and tested them for insecticidal activity. Based on the conventional and molecular tests, 12 different bacteria were isolated and identified as Curtobacterium sp., Rhodococcus sp., Arthrobacter nicotinovorans, Arthrobacter oxydans, Agrococcus jejuensis, Pseudomonas poae, Raoultella terrigena, Serratia sp., Lysinibacillus sphaericus, Stenotrophomonas rhizophila, Bacillus thuringiensis and Microbacterium oxydans. Mortalities due to the application of 0.5 mL of L. sphaericus, B. thuringiensis and R. terrigena at a density of OD600 1.89 were 60%, 70% and 60%, respectively, on adult P. prasina. This indicates that facultative cultivable bacterial flora isolated from P. prasina ...

This purpose of the study was the development of a microalgal-bacterial consortium to degrade phenolic compounds. Two microalgae were isolated and characterized from an olive wash water (OWW) storage basin and identified as Scenedesmus obliquus and Chlorella vulgaris according to their 18S rRNA gene sequences. The two strains were cultured in synthetic olive washing water medium containing phenolic compounds, which showed they were capable of growth in the presence of these substances, although they were sensitive to phenolic compounds and their growth decreased compared to controls grown in the absence of the compounds. Complementary experiments were carried out using a microalgalbacterial consortium containing the two microalgae and two bacterial strains able to degrade phenolic compounds (Raoultella terrigena and Pantoea agglomerans). The results showed that the microalgalbacterial consortium actively metabolized phenolic compounds with more that 99% of phenolic compounds removed at 48 h. The consortium also removed significant amounts of N and P from the liquid medium. The selected microalgal-bacterial consortium appeared to be a promising candidate for the bioremediation of OWW.

Agricultural production requires the continuous application of mineral fertilizers, which not only disrupt the natural balance but also reduce economic efficiency. The objective of this study was to understand the effects of plant growth-promoting rhizobacteria (PGPR) species (Bacillus megaterium M3, Bacillus subtilis OSU142, Bacillus pumilus C26, Paenibacillus polymyxa RC05, Azospirillum brasilense sp245, Burkholderia cepacia OSU7, B. cepacia OSU7 AMP Res and Raoultella terrigena TFi08) on their host plants. The maximum levels of arginine, histidine, tartaric acid, citric acid, and gibberellic acid were observed in B. megaterium M3 with maximum levels of glycine and threonine in B. subtilis OSU142, maximum lysine and lactic acid levels in R. terrigena TFi08 and maximum asparagine, serine, and abscisic acid levels in A. brasilense sp245. The highest Ca and P concentrations were observed in B. megaterium M3, while high concentrations of K, S, Na, Mn, Cd, and Ni were obtained from A. brasilense sp245. These data suggest that the B. megaterium M3, A. brasilense sp245, and R. terrigena TFi08 strains have the potential to be used as organic fertilizers to facilitate plant growth in sustainable and organic farming. (C) 2013 Elsevier Masson SAS. All rights reserved., Agricultural production requires the continuous application of mineral fertilizers, which not only disrupt the natural balance but also reduce economic efficiency. The objective of this study was to understand the effects of plant growth-promoting rhizobacteria (PGPR) species (Bacillus megateriumM3,Bacillus subtilisOSU142,Bacillus pumilusC26,Paenibacillus polymyxaRC05,Azospirillum brasilensesp245,Burkholderia cepaciaOSU7,B. cepaciaOSU7 AMP Res andRaoultella terrigenaTFi08) on their host plants. The maximum levels of arginine, histidine, tartaric acid, citric acid, and gibberellic acid were observed inB.megateriumM3 with maximum levels of glycine and threonine inB.subtilisOSU142, maximum lysine and lactic acid levels inR.terrigenaTFi08 and maximum asparagine, serine, and abscisic acid levels inA.brasilensesp245. The highest Ca and P concentrations were observed inB.megateriumM3, while high concentrations of K, S, Na, Mn, Cd, and Ni were obtained fromA.brasilensesp245. These data suggest that theB.megateriumM3,A.brasilensesp245, andR.terrigenaTFi08 strains have the potential to be used as organic fertilizers to facilitate plant growth in sustainable and organic farming.

The aim of this research was to develop technique to disinfect bacteria in water with chlorine. Response surface methodology (RSM) was applied for investigating the experimental design for disinfection the Klebsiella terrigena (Raoultella terrigena TISTR 1568). There were 20 experiments involving the three investigated variables of chlorine concentration, pH and disinfection time that were studied on R. terrigena TISTR 1568 to optimize the condition for disinfecting the R. terrigena TISTR 1568 to 99.9% death. Design of experiment was performed by application of 5-level-3-factors central composite design in order to study the optimum condition for disinfecting the R. terrigena TISTR 1568 to 99.9% death. The investigated results showed that the optimum condition was 1.2 ppm of chlorine concentration, at pH 7 and 5 min of disinfection time.