Impact of phosphate solubilizing bacteria on wheat (Triticum aestivum ) in the presence of pesticides / Impacto das bactérias solubilizantes de fosfato no trigo (Triticum aestivum ) na presença de pesticidas

Abstract Three phosphate solubilizing bacteria were isolated and identified by 16S rRNA sequencing as Pseudomonas putida, Pseudomonas sp and Pseudomonas fulva . The strains were subjected to plant biochemical testing and all the PGPR attributes were checked in the presence of pesticides (chlorpyrifos and pyriproxyfen). The phosphate solubilizing index of strain Ros2 was highest in NBRIP medium i.e 2.23 mm. All the strains showed acidic pH (ranges from 2.5-5) on both medium i.e PVK and NBRIP. Strain Ros2 was highly positive for ammonia production as well as siderophore production while strain Rad2 was positive for HCN production. The results obtained by the strains Rad1, Rad2 and Ros2 for auxin production were 33.1, 30.67 and 15.38 µg ml-1, respectively. Strain Rad1 showed 16% increase in percentage germination in comparison to control in the presence of pesticide stress. Most promising results for chlorophyll content estimation were obtained in the presence of carotenoids upto 6 mgg-1 without stress by both strains Rad1 and Rad2. Study suggests that especially strain Ros2 can enhance plant growth parameters in the pesticide stress.

Resumo Três bactérias solubilizantes de fosfato foram isoladas e identificadas por seqüenciamento de rRNA 16S como Pseudomonas putida, Pseudomonas sp e Pseudomonas fulva. As estirpes foram submetidas a testes bioquímicos de plantas e todos os atributos PGPR foram verificados na presença de pesticidas (clorpirifos e piriproxifeno). O índice de solubilização de fosfato da estirpe Ros2 foi mais elevado no meio NBRIP, isto é, 2,23 mm. Todas as estirpes apresentaram um pH ácido (varia de 2,5-5) em ambos os meios, isto é PVK e NBRIP. A estirpe Ros2 foi altamente positiva para a produção de amoníaco, bem como a produção de sideróforos enquanto a estirpe Rad2 foi positiva para a produção de HCN. Os resultados obtidos pelas estirpes Rad1, Rad2 e Ros2 para a produção de auxina foram 33,1, 30,67 e 15,38 μg ml-1 , respectivamente. A deformação Rad1 mostrou aumento de 16% na germinação percentual em comparação com o controlo na presença de stress de pesticida. Os resultados mais promissores para a estimativa do teor de clorofila foram obtidos na presença de carotenóides até 6 mgg-1 sem estresse por ambas as cepas Rad1 e Rad2. Estudo sugere que especialmente a estirpe Ros2 pode melhorar parâmetros de crescimento de plantas no estresse de pesticidas.

First comprehensive report of bacteria spp. associated with cloaca of Laudakia nupta (Sauria: Agamidae) in Iran using molecular studies / 한국실험동물학회지

Iran bears a remarkable variety of reptiles. One of the lizard families occurring in Iran is the Family Agamidae which is widely are distributed throughout the old world. The large-scaled rock agamid, Laudakia nupta, is one of the well-known agamid. There are few reports of cloacal microbial on reptiles hence their function in cloacae remains unknown. Laudakia nupta usually live in rural and urban areas and close vicinity to man, they are likely to play an important role in the spread of disease that may be caused by these microorganisms and their transmission to man. Therefore, the aim of this study was to identify the bacterial flora colonizing the cloacal region of Laudakia nupta using molecular studies. The cloacal fluids were directly placed on nutrient agar (NA) plates and incubated at 25 ± 2 ℃ for 48 h. The resulting bacterial colonies were transferred to fresh nutrient agar (NA) plates for molecular studies. Twelve isolates were obtained from 17 specimens of Laudakia nupta. All bacteria isolates were identified as Bacillus subtillis (5), Bacillus cereus (4), Bacillus sp. (1), Pseudomonas putida (1), and Pseudomonas sp. (1) based on partial sequences of the 16 s rRNA gene. This is the first comprehensive report of bacteria spp. associated with cloaca of Laudakia nupta using molecular studies. In this research, we found that Laudakia nupta can be a carrier of bacteria which can transfer microorganisms to hosts.

Cloning and characterisation of four catA genes located on the chromosome and large plasmid of Pseudomonas putida ND6

Background: Although the functional redundancy of catechol 1,2-dioxygenase (C12O) genes has been reported in several microorganisms, limited enzymes were characterised, let alone the advantage of the coexistence of the multiple copies of C12O genes. Results: In this study, four novel C12O genes, designated catA, catAI, catAII and catAIII, in the naphthalene-degrading strain Pseudomonas putida ND6, were cloned and characterised. Phylogenetic analysis of their deduced amino acid sequences revealed that the four C12O isozymes each formed independent subtrees, together with homologues from other organisms. All four enzymes exhibited maximum activity at pH 7.4 and higher activity in alkaline than in acidic conditions. Furthermore, CatA, CatAI and CatAIII were maximally active at a temperature of 45°C, whereas a higher optimum temperature was observed for CatAII at a temperature of 50°C. CatAI exhibited superior temperature stability compared with the other three C12O isozymes, and kinetic analysis indicated similar enzyme activities for CatA, CatAI and CatAII, whereas that of CatAIII was lower. Significantly, among metal ions tested, only Cu2+ substantially inhibited the activity of these C12O isozymes, thus indicating that they have potential to facilitate bioremediation in environments polluted with aromatics in the presence of metals. Moreover, gene expression analysis at the mRNA level and determination of enzyme activity clearly indicated that the redundancy of the catA genes has increased the levels of C12O. Conclusion: The results clearly imply that the redundancy of catA genes increases the available amount of C12O in P. putida ND6, which would be beneficial for survival in challenging environments.

Simultaneous biodegradation of phenol and cyanide present in coke-oven effluent using immobilized Pseudomonas putida and Pseudomonas stutzeri

ABSTRACT Discharge of coke-oven wastewater to the environment may cause severe contamination to it and also threaten the flora and fauna, including human beings. Hence before dumping it is necessary to treat this dangerous effluent in order to minimize the damage to the environment. Conventional technologies have inherent drawbacks however, biological treatment is an advantageous alternative method. In the present study, bacteria were isolated from the soil collected from the sites contaminated by coke-oven effluent rich in phenol and cyanide. Nucleotides sequence alignment and phylogenetic analysis showed the identity of the selected phenol and cyanide degrading isolates NAUN-16 and NAUN-1B as Pseudomonas putida and Pseudomonas stutzeri, respectively. These two isolates tolerated phenol up to 1800 mg L-1 and cyanide up to 340 mg L-1 concentrations. The isolates were immobilized on activated charcoal, saw dust and fly ash. The effluent was passed through the column packed with immobilized cells with a flow rate of 5 mL min-1. The isolates showed degradation of phenol up to 80.5% and cyanide up to 80.6% and also had the ability to reduce biological oxygen demand, chemical oxygen demand and lower the pH of effluent from alkaline to near neutral. The study suggests the utilization of such potential bacterial strains in treating industrial effluent containing phenol and cyanide, before being thrown in any ecosystem.

Dual infection by burkholderia cepacia and pseudomonas putida in an infective endocarditis case

Infective endocarditis is rarely caused by Burkholderia cepacia

Pseudomonas putida has not been reported to cause infective endocarditis so far. This is the first case of infective endocarditis being reported, that is caused by Pseudomonas putida and Burkholderia cepacia in an immunocompetent host with no predisposing factors. Aortic valve replacement surgery was carried out and antibiotics were given, to which the patient responded well and recovered

Bioconversion of mixed free fatty acids to poly-3-hydroxyalkanoates by Pseudomonas putida BET001 and modeling of its fermentation in shake flasks

Background: The paper reports on the utilization of palm kernel oil (PKO) as a low cost renewable substrate for medium-chain-length poly-3-hydroxyalkanoates (mcl-PHA) production by Pseudomonas putida BET001. Investigation on the effects of selected key variables on growth, mixed free fatty acids consumption and mcl-PHA production by the bacterial culture in the shaken flask system were carried out along with its kinetic modeling. Results: The biomass production, fatty acids consumption and mcl-PHA production were found favorable when the strain was cultured in mineral medium at pH 6-7,28°C, aeration surface-to-volume ratio of 0.4 x 10(6) m-1, 250 rpm agitation rate for 48 h. Mcl-PHA production by this strain showed mixed growth and non-growth associated components as described by Luedeking-Piret kinetic model. Conclusion: The findings of this study provided add to the literature on key variables in for achieving good microbial growth and mcl-PHA production in shake flasks culture. In addition, suitable kinetic model to describe cultivation in this system was also presented.

GPo1 alkB gene expression for improvement of the degradation of diesel oil by a bacterial consortium

To facilitate the biodegradation of diesel oil, an oil biodegradation bacterial consortium was constructed. The alkane hydroxylase (alkB) gene of Pseudomonas putida GPo1 was constructed in a pCom8 expression vector, and the pCom8-GPo1 alkB plasmid was transformed into Escherichia coli DH5α. The AlkB protein was expressed by diesel oil induction and detected through SDS-polyacrylamide gel electrophoresis. The culture of the recombinant (pCom8-GPo1 alkB/E. coli DH5α) with the oil biodegradation bacterial consortium increased the degradation ratio of diesel oil at 24 h from 31% to 50%, and the facilitation rates were increased as the proportion of pCom8-GPo1 alkB/E. coli DH5α to the consortium increased. The results suggested that the expression of the GPo1 gene in E. coli DH5α could enhance the function of diesel oil degradation by the bacterial consortium.

Aerobic cyanide degradation by bacterial isolates from cassava factory wastewater

Ten bacterial strains that utilize cyanide (CN) as a nitrogen source were isolated from cassava factory wastewater after enrichment in a liquid media containing sodium cyanide (1 mM) and glucose (0.2% w/v). The strains could tolerate and grow in cyanide concentrations of up to 5 mM. Increased cyanide levels in the media caused an extension of lag phase in the bacterial growth indicating that they need some period of acclimatisation. The rate of cyanide removal by the strains depends on the initial cyanide and glucose concentrations. When initial cyanide and glucose concentrations were increased up to 5 mM, cyanide removal rate increased up to 63 and 61 per cent by Bacillus pumilus and Pseudomonas putida. Metabolic products such as ammonia and formate were detected in culture supernatants, suggesting a direct hydrolytic pathway without an intermediate formamide. The study clearly demonstrates the potential of aerobic treatment with cyanide degrading bacteria for cyanide removal in cassava factory wastewaters.

Influences of extracellular polymeric substances (EPS) for autoaggregation of Pseudomonas putida CP1 during growth on mono-chlorophenol

Aims: Pseudomonas putida CP1 exhibits substrate-dependent autoaggregation during the degradation of 100 ppm 2- chlorophenol, 100 ppm 3-chlorophenol and 200 ppm 4-chlorophenol. This study discussed the production of extracellular polymeric substances (EPS) by the organism for the formation of aggregates. Methodology and results: Aggregation was accompanied by the production of extracellular polymeric substances (EPS). The extent of EPS production and the size of the aggregates increased with increasing stress as did the aggregation index and the hydrophobicity of the cells. A biochemical analysis of the EPS showed that the main constituents were carbohydrate (40% w/v) and protein (50% w/v) together with lower levels of DNA (<10% w/v). Conclusion, significance and impact study: Given that the aggregated form of the bacterium has shown potential for use in bioaugmentation, an in-depth understanding of the phenomenon could enhance the use of this organism in biological wastewater treatment systems.

Prevalence of healthcare-associated infections among the pediatric patients admitted at Philippine General Hospital from the years 2011-2014

@#<p style="text-align: justify;"><strong>INTRODUCTION:</strong> Healthcare associated infections (HAIs) continue to be a major public health concern throughout the world particularly in developing countries wherein prevalence rates range from 5.7%-19.1%.</p> <p style="text-align: justify;"><strong>OBJECTIVES:</strong> The aims of this study were to determine the prevalence of HAIs among pediatric patients admitted at Philippine General Hospital and to describe the trends of annual prevalence of HAIs in relation to infection control programs implemented.</p> <p style="text-align: justify;"><strong>METHODOLOGY:</strong> A retrospective study was conducted at the 145-bed capacity wards and intensive care units of the Department of Pediatrics, Philippine General Hospital (PGH) from January 2011 to December 2014 wherein HAI records from the database of the Section of Infectious and Tropical Disease in Pediatrics (INTROP) were reviewed. The following data were collected and encoded: (1) number of patients admitted in the different areas: Pediatric wards (Ward 9 and Ward 11), PICU and NICU; (2) number of patients who developed HAIs; and (3) microbial isolates, sites and antibiotic susceptibility results. Trends of yearly prevalence of HAIs in relation to infection programs implemented were determined, and the microbial isolates and their antibiotic sensitivity patterns were described.</p> <p style="text-align: justify;"><strong>RESULTS:</strong> Among 30,032 pediatric patients at risk for HAIs and admitted from January 2011 to December 2014, the prevalence of HAI was 11.37%. There was a decreasing trend in the yearly HAI rates from 2011 to 2014 which coincided with implementation of infection control programs and hiring of a part-time infection control nurse in 2012. The prevalence of HAIs was highest at the PICU (15.17%- 27.81%) followed by the two Pediatric wards, ward 9 (9.03%-19.87%) and ward 11(8.75%-14.76%) and lowest at the NICU (7.52%-9.44%). Top isolates were Pseudomonas putida, Pseudomonas aeruginosa, and Klebsiella pneumonia. Pseudomonas organisms were still sensitive to Ceftazidime, and Klebsiella to Meropenem.</p> <p style="text-align: justify;"><strong>CONCLUSION:</strong> The overall HAI prevalence during the 4-year study period was 11.37% (9.14% - 13.65%) comparable to those seen in developing countries. There was a decreasing trend of prevalence annually that coincided with the implementation of various infection control programs and the hiring of a part-time infection control nurse. The microbial isolates obtained vary per area but overall the same organisms were isolated during the study periods which were susceptible to the empiric treatment given.</p>

Health impact assessment of decreases in PM10 and ozone concentrations in the Mexico City Metropolitan Area: A basis for a new air quality management program / Evaluación de impacto en salud ante reducciones de PM10 y ozono en la Zona Metropolitana del Valle de México: Base para un nuevo programa de calidad del aire

Objective. To conduct a health impact assessment (HIA) to quantify health benefits for several PM and O3 air pollution reduction scenarios in the Mexico City Metropolitan Area (MCMA). Results from this HIA will contribute to the scientific support of the MCMA air quality management plan (PROAIRE) for the period 2011-2020. Materials and methods. The HIA methodology consisted of four steps: 1) selection of the air pollution reduction scenarios, 2) identification of the at-risk population and health outcomes for the 2005 baseline scenario, 3) selection of concentration-response functions and 4) estimation of health impacts. Results. Reductions of PM10 levels to 20 μg/m³ and O3 levels to 0.050ppm (98 µg/m³) would prevent 2300 and 400 annual deaths respectively. The greatest health impact was seen in the over-65 age group and in mortality due to cardiopulmonary and cardiovascular disease. Conclusion. Improved air quality in the MCMA could provide significant health benefits through focusing interventions by exposure zones.

Objetivo. Realizar una evaluación de impacto en salud (EIS) que documente los beneficios en salud ante diversos escenarios de reducción de PM10 y O3 en el aire de la Zona Metropolitana del Valle de México (ZMVM). Los resultados contribuyen al sustento científico del plan de gestión de calidad del aire (PROAIRE 2011-2020). Material y métodos. La metodología de EIS comprende cuatro pasos: 1) selección de los escenarios de reducción, 2) identificación de la población en riesgo y de los eventos en salud para el año basal 2005, 3) selección de las funciones de concentración-respuesta y 4) estimación del impacto en la salud. Resultados. Reducciones de PM10 a 20μg/m³ y de O3 a 0.050ppm (98 µg/m³) evitarían, respectivamente, cerca de 2 300 y 400 muertes por año. El mayor impacto se observa en el grupo de más de 65 años y en la mortalidad por causas cardiopulmonares y cardiovasculares. Conclusiones. Mejorar la calidad del aire en la ZMVM podría reflejar importantes beneficios para la salud focalizados por zonas o áreas de exposición.

"El hecho de que sean más mujeres, no garantiza nada": feminización y experiencias de las mujeres en la ginecobstetricia en México / "The fact that there are more women doesn't guarantee anything": The feminization of obstetrics and gynecology and the experiences of female medical professionals in Mexico

En el marco de la creciente feminización de la profesión médica en México, el artículo indaga sobre las características de este proceso para el caso de la ginecobstetricia. Considerando la feminización como un proceso de cambio, que se analiza cuantitativa y cualitativamente, el artículo se detiene en especial en las experiencias de las mujeres ginecobstetras, experiencias que se dan en el seno de una especialidad que, desde sus orígenes, funcionó como un dispositivo de control del cuerpo de las mujeres. Basado en una investigación etnográfica, el artículo combina fuentes estadísticas, de archivo y de observación de campo. El material que surge de las entrevistas muestra las experiencias y tensiones que viven las ginecobstetras en este contexto.

In the framework of an increasing feminization of the medical profession in Mexico, this article explores the characteristics of this process in the obstetrics and gynecology specialty. Understanding feminization as a process of change to be analyzed both quantitatively and qualitatively, the article focuses special attention on the experiences of female obstetrician-gynecologists within a medical specialty that has since its origins functioned as a mechanism of control over women's bodies. Based on ethnographic research, the article combines statistical and archival sources and field observation. The interviews reveal the experiences and tensions women obstetrician-gynecologists encounter in this context.

Screening and optimization of low-cost medium for Pseudomonas putida Rs-198 culture using RSM

The plant growth-promoting rhizobacterial strain Pseudomonas putida Rs-198 was isolated from salinized soils from Xinjiang Province. We optimized the composition of the low-cost medium of P. putida Rs-198 based on its bacterial concentration, as well as its phosphate-dissolving and indole acetic acid (IAA)-producing capabilities using the response surface methodology (RSM), and a mathematical model was developed to show the effect of each medium component and its interactions on phosphate dissolution and IAA production. The model predicted a maximum phosphate concentration in medium containing 63.23 mg/L inorganic phosphate with 49.22 g/L corn flour, 14.63 g/L soybean meal, 2.03 g/L K2HPO4, 0.19 g/L MnSO4 and 5.00 g/L NaCl. The maximum IAA concentration (18.73 mg/L) was predicted in medium containing 52.41 g/L corn flour, 15.82 g/L soybean meal, 2.40 g/L K2HPO4, 0.17 g/L MnSO4 and 5.00 g/L NaCl. These predicted values were also verified through experiments, with a cell density of 10(13) cfu/mL, phosphate dissolution of 64.33 mg/L, and IAA concentration of 18.08 mg/L. The excellent correlation between predicted and measured values of each model justifies the validity of both the response models. The study aims to provide a basis for industrialized fermentation using P. putida Rs-198.

Further characterization of o-nitrobenzaldehyde degrading bacterium Pseudomonas sp: ONBA-17 and deduction on its metabolic pathway

A previously reported o-nitrobenzaldehyde (ONBA) degrading bacterium Pseudomonas sp. ONBA-17 was further identified and characterized. Based on results of DNA base composition and DNA-DNA hybridization, the strain was identified as P. putida. Its degradation effect enhanced with increase of inoculum amount and no lag phase was observed. Higher removal rate was achieved under shaking conditions. All tested ONBA with different initial concentrations could be completely degraded within 5 d. In addition, degradative enzyme(s) involved was confirmed as intra-cellular distributed and constitutively expressed. Effects of different compounds on relative activity of degradative enzyme(s) within cell-free extract were also evaluated. Finally, 2-nitrobenzoic acid and 2, 3-dihydroxybenzoic acid were detected as metabolites of ONBA degradation by P. putida ONBA-17, and relevant metabolic pathway was preliminary proposed. This study might help with future research in better understanding of nitroaromatics biodegradation.

Temporomandibular Disorders in a Sample Population of the Brazilian Northeast

Temporomandibular disorder (TMD) is a common condition. This study is part of a research group and it investigated the prevalence of TMD and myofascial pain and its association with gender, age and socioeconomic class. The sample comprised 100 subjects, aged 15 to 70, users of the Family Health Units' services, in the city of Recife, PE, Brazil. The TMD degree was evaluated using the Research Diagnostic Criteria for TMD and socioeconomic class by the Economic Classification Criteria Brazil. Categorical variables were analyzed by chi-square test for proportions and Fisher's exact test for 2x2 tables, and binary logistic analysis to track the relationship between the independent and dependent variables. According to the results, 42% of the subjects had TMD and 14% myofascial pain. No statistically significant association could be found between TMD and gender or socioeconomic class, but it was found to have statistically significant association with age, and myofascial pain was associated with socioeconomic class. Considering that the results of the present study should be confirmed by further studies and the fact that this was a pilot study, the prevalence must be analyzed with caution.

Disfunção temporomandibular (DTM) é uma condição comum. Este estudo é parte de um grupo de pesquisa e investigou a prevalência de DTM e dor miofascial e suas associações com sexo, idade e classe socioeconômica. A amostra foi composta por 100 indivíduos, com idades entre 15 e 70 anos, usuários das Unidades de Saúde da Família, na cidade de Recife, PE. O grau de DTM foi avaliado usando os Critérios de Diagnósticos Científicos em DTM, e classe socioeconômica com o Critério de Classificação Econômica Brasil. As variáveis categóricas foram analisadas pelo teste do qui-quadrado para proporções e teste exato de Fisher para tabelas 2x2, e a análise logística binária para traçar a relação entre as variáveis independentes e dependentes. De acordo com os resultados, 42% dos indivíduos tinham DTM e 14% dor miofascial. Não houve associação estatisticamente significativa entre DTM e sexo ou classe socioeconômica, mas houve associação estatisticamente significativa com a idade e a dor miofascial foi associada com a classe socioeconômica. Considerando-se que os resultados do presente estudo devam ser confirmados em outros estudos e por causa de sua natureza piloto, a prevalência deve ser analisada com cautela.

Growth kinetics, effect of carbon substrate in biosynthesis of mcl-PHA by Pseudomonas putida Bet001

Growth associated biosynthesis of medium chain length poly-3-hydroxyalkanoates (mcl-PHA) in Pseudomonas putida Bet001 isolated from palm oil mill effluent was studied. Models with substrate inhibition terms described well the kinetics of its growth. Selected fatty acids (C8:0 to C18:1) and ammonium were used as carbon and nitrogen sources during growth and PHA biosynthesis, resulting in PHA accumulation of about 50 to 69% (w/w) and PHA yields ranging from 10.12 g L-1 to 15.45 g L-1, respectively. The monomer composition of the PHA ranges from C4 to C14, and was strongly influenced by the type of carbon substrate fed. Interestingly, an odd carbon chain length (C7) monomer was also detected when C18:1 was fed. Polymer showed melting temperature (Tm) of 42.0 (± 0.2) °C, glass transition temperature (Tg) of -1.0 (± 0.2) °C and endothermic melting enthalpy of fusion (ΔHf) of 110.3 (± 0.1) J g-1. The molecular weight (Mw) range of the polymer was relatively narrow between 55 to 77 kDa.

Profile of nosocomial infections among children with acute lymphoblastic leukemia

@#<p style="text-align: justify;"><strong>OBJECTIVES:</strong> The study aimed to determine the frequency and clinical profile of nosocomial infections among pediatric patients with Acute Lymphoblastic Leukemia (ALL) admitted at the Philippine General Hospital from January 2010 to December 2011.<br /><strong>METHODOLOGY:</strong> This is a descriptive cross sectional study involving the review of medical records of pediatric patients with ALL under the charity service of the Section of Pediatric Hematology and Oncology of Philippine General Hospital (PGH). The frequency, clinical presentation, outcome, causes of death and isolated organisms from sterile sites were determined. Fischer's Exact test was used to assess correlation between variables with Gram-negative bacterial infection and mortality.<br /><strong>RESULTS:</strong> There were 80 documented nosocomial infections among 45 pediatric patients with ALL. The incidence was 9.22 per 100 admissions. The majority presented initially with fever (50%) and 37 (82%) had neutropenia. Blood stream infections were present in 33 (73%) out of 45 pediatric ALL patients. Gram-negative organisms (76%), particularly Pseudomonas putida (33%), Pseudomonas aeruginosa (12%) and Burkholderia pseudomallei (12%) were isolated in majority of patients. About 42.2% of the 45 patients had resolution of the infection and 26.7% resulted to death primarily caused by septic shock in 7 (58.3%) of the 12 patients identified. Presence of fever (p- value 0.011, RR 2.1094) was associated with presence of Gram-negative bacteria at 5% level of significance and with 2.109 times more risk to having a gram-negative infection. There was no significant correlation between mortality and symptoms of infection.<br /><strong>CONCLUSION:</strong> Nosocomial infections remain to be significant cause of morbidity and death among pediatric patients with ALL. Gram negative infections were the most common cause of sepsis in these patients. One fourth of the patients with nosocomial infections died.</p>

Screening, identification and culture optimization of a newly isolated aromatic nitrilase-producing bacterium--Pseudomonas putida CGMCC3830 / 生物工程学报

Microbial nitrilases have attracted increasing attention in nitrile hydrolysis for carboxylic acid production in recent years. A bacterium with nitrilase activity was isolated and identified as Pseudomonas putida CGMCC3830 based on its morphology, physiological and biochemical characteristics, as well as 16S rRNA gene sequence. The nitrilase production was optimized by varying culture conditions using the one-factor-at-a-time method and response surface methodology. Glycerol 13.54 g/L, tryptone 11.59 g/L, yeast extract 5.21 g/L, KH2PO4 1 g/L, NaCl 1 g/L, urea 1 g/L, initial pH 6.0 and culture temperature 30 degrees C were proved to be the optimal culture conditions. It resulted in the maximal nitrilase production of 36.12 U/mL from 2.02 U/mL. Investigations on substrate specificity demonstrate P. putida nitrilase preferentially hydrolyze aromatic nitriles. When applied in nicotinic acid synthesis, 2 mg/mL P. putida cells completely hydrolyzed 20.8 g/L 3-cyanopyridine into nicotinic acid in 90 min. The results indicated P. putida CGMCC3830 displayed potential for industrial production of nicotinic acid.

Two main tropane alkaloids variations of black henbane [hyoscyamus niger] under pgprs inoculation and water deficit stress induction at flowering stage

Plants infection with microorganisms as well as physical factors such as osmotic stresses especially drought stress induced particular secondary metabolite production. Plant root and shoot hyoscyamine [HYO] and scopolamine [SCO] variations were investigated under three water deficit stress [WDS] levels as 30 [W1], 60 [W2] and 90% [W3] water depletion of field capacity and Pseudomonas putida [PP] and P. fluoresence [PF] strains inoculation at flowering stage. Seedling radicles and culture media were inoculated with PP and PF [10[9] CFU/ml] strains. Monitoring of soil moisture levels was conducted using gravimetric method. Alkaloids extracted were identified by gas chromatography [GC] and gas chromatography-mass spectrometry [GC-MS] analysis. Results revealed that HYO was the prevalent alkaloid in root and shoot organs. The highest ratio of SCO to HYO [0.53] and the highest alkaloids both HYO and SCO content in root and shoot was observed in W3PF treatment. The largest total alkaloids [HYO+SCO] yield [25.7 mg.plant[-1]] was showed in PP treated plants under W1 conditions. Integrative use of effective Pseudomonades strains and WDS sounds to be an encouraging and eco-friendly strategy for increasing tropane alkaloids yield and content in Hyoscyamus niger root and shoot parts

In situ biosurfactant production and hydrocarbon removal by Pseudomonas putida CB-100 in bioaugmented and biostimulated oil-contaminated soil

In situ biosurfactant (rhamnolipid) production by Pseudomonas putida CB-100 was achieved during a bioaugmented and biostimulated treatment to remove hydrocarbons from aged contaminated soil from oil well drilling operations. Rhamnolipid production and contaminant removal were determined for several treatments of irradiated and non-irradiated soils: nutrient addition (nitrogen and phosphorus), P. putida addition, and addition of both (P. putida and nutrients). The results were compared against a control treatment that consisted of adding only sterilized water to the soils. In treatment with native microorganisms (non-irradiated soils) supplemented with P. putida, the removal of total petroleum hydrocarbons (TPH) was 40.6%, the rhamnolipid production was 1.54 mg/kg, and a surface tension of 64 mN/m was observed as well as a negative correlation (R = -0.54; p < 0.019) between TPH concentration (mg/kg) and surface tension (mN/m), When both bacteria and nutrients were involved, TPH levels were lowered to 33.7%, and biosurfactant production and surface tension were 2.03 mg/kg and 67.3 mN/m, respectively. In irradiated soil treated with P. putida, TPH removal was 24.5% with rhamnolipid generation of 1.79 mg/kg and 65.6 mN/m of surface tension, and a correlation between bacterial growth and biosurfactant production (R = -0.64; p < 0.009) was observed. When the nutrients and P. putida were added, TPH removal was 61.1%, 1.85 mg/kg of biosurfactants were produced, and the surface tension was 55.6 mN/m. In summary, in irradiated and non-irradiated soils, in situ rhamnolipid production by P. putida enhanced TPH decontamination of the soil.