A spontaneously occurring variation of Aerobacter levanicum, affecting the appearance of colonies on sucrose agar (opaque to translucent colony form), has been observed and studied. This appears to be a mutation that is accompanied by a significant increase in levansucrase (EC 18.104.22.168) activity, in levan production, and by a change in some of the properties of levansucrase. PMID:4745425
The microbial transformation rates of propanil, a commonly used herbicide, were investigated using water from a pristine lake in northeast Georgia. Microbial degradation rates were measured using natural water microflora amended with five bacterial species (Aerobacter aerogenes, ...
Full Text Available 1e-09 4 ( AY068301 ) Schmidtea mediterranea clone H.44.7a(T3) unknown ... 64 1e-09 2 ( DY891741 ) CeleSEQ8396 Cunninghamella elegan... ... 36 1e-04 4 ( X16908 ) Yeast SRH1 gene for Srh1p, a homologue of the 54K s... 48 1e-04 3 ( AJ777995 ) Populus euph...aerobacter pseudethanol... 196 3e-48 CP001102_912( CP001102 |pid:none) Candi...08798_654( BX908798 |pid:none) Parachlamydia-related symbiont U... 179 4e-43 CP001101_1233( CP001101 |pid:none) Chlorobium pha...00422_795( CP000422 |pid:none) Pediococcus pentosaceus ATCC 257... 174 2e-41 CP000411_409( CP000411 |pid:none
S-(beta-Aminoethyl)-L-cysteine, a sulfur analogue of lysine inhibited strongly growth of Escherichia coli A-19, and weakly that of Corynebacterium sp. isolated from soil, but did not inhibit growth of Aerobacter aerogenes. In Corynebacterium sp. the inhibitory effect was markedly enhanced in the presence of L-threonine. The inhibition of growth by S-(beta-aminoethyl)-L-cysteine was rapidly reversed by the addition of L-lysine. S-(beta-Aminoethyl)-L-cysteine inhibited protein synthesis and the activity of lysyl-tRNA synthetase from E. coli and A. aerogenes. All the other lysine analogues tested inhibited the activity of enzyme, but S-(beta-aminoethyl)-L-cysteine derivatives, S-(beta-N-acetyl-aminoethyl)-L-cysteine and S-(beta-aminoethyl)-alpha-N-acetyl-L-cysteine were not effective. (auth.)
Zhang, G.; Dong, H.; Jiang, H.; Kukkadapu, R.K.; Kim, J.; Eberl, D.; Xu, Z.
Iron-reducing and oxidizing microorganisms gain energy through reduction or oxidation of iron, and by doing so play an important role in the geochemical cycling of iron. This study was undertaken to investigate mineral transformations associated with microbial reduction of Fe3+ and oxidation of Fe2+ in solid minerals. A fluid sample from the 2450 m depth of the Chinese Continental Scientific Drilling project was collected, and Fe3+-reducing and Fe2+-oxidizing microorganisms were enriched. The enrichment cultures displayed reduction of Fe3+ in nontronite and ferric citrate, and oxidation of Fe2+ in vivianite, siderite, and monosulfide (FeS). Additional experiments verified that the iron reduction and oxidation was biological. Oxidation of FeS resulted in the formation of goethite, lepidocrocite, and ferrihydrite as products. Although our molecular microbiological analyses detected Thermoan-aerobacter ethanolicus as a predominant organism in the enrichment culture, Fe3+ reduction and Fe2+ oxidation may be accomplished by a consortia of organisms. Our results have important environmental and ecological implications for iron redox cycling in solid minerals in natural environments, where iron mineral transformations may be related to the mobility and solubility of inorganic and organic contaminants.
Five patients with blind loop syndrome (Billroth II) were examined by measuring 14CO2 specific activity of expired breath samples taken at intervals after a meal containing glycine-1-14C cholate. The 5 patients tested showed a marked increase of 14CO2 specific activity. Furthermore, the ability of deconjugation of bacteria isolated from the jejunal fluids in the efferent loop of these patients was tested by thin-layer chromatography. The bacterial species identified from the samples were as follows: enterococcus, Lactobacillus buchneri, L. bifidus, L. brevis, Eubacterium lentum, Bacteroides vulgaricus, B. filamentosum, Corynebacterium granulosum, Escherichia coli, Staphylococcus epidermidis, and Aerobacter aerogenes. These species of bacteria, except E. coli and A. aerogenes, showed the deconjugation ability by which conjugated bile acids in ox gall was hydrolyzed. Administration of chloramphenicol to the 5 patients reduced 14CO2 specific activity significantly. On the other hand, 9 healthy men who were tested showed a flat curve, and 8 of the 9 had no growth of bacteria isolated from the jejunal fluids. The remaining healthy man showed an over growth of E. coli and Pseudomonas aeruginosa, but the species did not have the ability of deconjugation
Miller, Chris H.; Somers, Penelope J. B.
Actinomyces viscosus ATCC 15987 was examined for its ability to hydrolyze its own levan. Washed whole cells and an ammonium sulfate fraction from cell-free culture fluids were shown to possess levan hydrolase activity. Analyses of reaction mixtures by gel filtration and thin-layer chromatography demonstrated that the product of levan hydrolysis was free fructose. The cell-associated and extracellular enzyme preparations also hydrolyzed inulin and the levans synthesized by Aerobacter levanicum and Bacillus subtilis. Growth of A. viscosus in media supplemented with 0.1% A. viscosus levan resulted in a 33-fold increase and a 7-fold increase in the specific activities of the respective extracellular and cell-associated enzymes when compared with those from 55 mM glucose cultures. Growth in the presence of 29.2 mM sucrose resulted in a 28-fold increase and a 5-fold increase in the specific activities of the respective enzymes when compared with those from the glucose cultures. The extracellular enzyme exhibited high activity over a wide pH range, with 87 and 89% of its pH 6.0 optimum activity at pH 5.0 and 7.0, respectively. The cell-associated enzyme also exhibited optimum activity at pH 6.0, but this was decreased to 10 and 20% at pH 5.0 and 7.0, respectively. Analysis for the presence of extracellular levan during growth of A. viscosus in sucrose broths demonstrated that peak levan concentrations occurred during the mid-exponential to late-exponential phase of growth followed by a rapid decline in extracellular levan as a result of levan hydrolase activity. Images PMID:32137
Shakeel Ahmed Adhoni; Basappa Basawanneppa Kaliwal
Objective:To determine the presence of bioactive molecules and to check their antimicrobial activity from green algaeChlorella vulgaris (AS-3) (C. vulgaris) isolated from Unkal Lake in Dharwad District, Karnataka, India. Methods: Based on the polarity, benzene, chloroform, ethyl acetate, ethanol, hexane, methanol, petroleum ether and distilled water were the solvents used for the preparation of algal extracts using Soxhlet apparatus, which were further subjected to phytochemical analysis and screening of antimicrobial activity. Human pathogens such asStaphylococcus aureus, Corynebacterium,Bacillus subtilis,Streptococcus,Escherichia coli,Salmonella Paratyphi B, Klebsiella pneumoniae,Aerobacter aerogenes,Candida albicans andAspergillus niger were used for antimicrobial assay. Standard methods were followed for qualitative estimation of phytochemicals. Results: Phytochemical determination of bioactive molecules showed the presence of alkaloids, flavonoids, glycosides, carotenoids, phenols, lignins, saponins, sterols, tannins, reducing sugars, volatile oil, fats, amino acids and carbohydrates. In vitro analysis of organic solvent extracts ofC. vulgaris, a green microalgae, showed an activity by suppressing the proliferation of bacterial, fungal and human pathogens. Four extracts (chloroform, ethyl acetate, hexane and methanol) showed effective inhibitory activity against the tested pathogens. Depending on the percentage of bioactive molecules present in each of the organic extracts, different extracts showed different inhibition zone diameters against the pathogens. Among the eight organic extracts used for the study, excellent inhibitory effects were shown by chloroform and methanol extracts. Conclusions: The present study indicates that green algaeC. vulgaris is rich in natural compounds which are highly important in pharmacology and nutraceuticals. Although the presence of bioactive molecules is very less in the algae, excellent effect on the microbial pathogens was
Shakeel Ahmed Adhoni
Full Text Available Objective: To determine the presence of bioactive molecules and to check their antimicrobial activity from green algae Chlorella vulgaris (AS-3 (C. vulgaris isolated from Unkal Lake in Dharwad District, Karnataka, India. Methods: Based on the polarity, benzene, chloroform, ethyl acetate, ethanol, hexane, methanol, petroleum ether and distilled water were the solvents used for the preparation of algal extracts using Soxhlet apparatus, which were further subjected to phytochemical analysis and screening of antimicrobial activity. Human pathogens such as Staphylococcus aureus, Corynebacterium, Bacillus subtilis, Streptococcus, Escherichia coli, Salmonella Paratyphi B, Klebsiella pneumoniae, Aerobacter aerogenes, Candida albicans and Aspergillus niger were used for antimicrobial assay. Standard methods were followed for qualitative estimation of phytochemicals. Results: Phytochemical determination of bioactive molecules showed the presence of alkaloids, flavonoids, glycosides, carotenoids, phenols, lignins, saponins, sterols, tannins, reducing sugars, volatile oil, fats, amino acids and carbohydrates. In vitro analysis of organic solvent extracts of C. vulgaris, a green microalgae, showed an activity by suppressing the proliferation of bacterial, fungal and human pathogens. Four extracts (chloroform, ethyl acetate, hexane and methanol showed effective inhibitory activity against the tested pathogens. Depending on the percentage of bioactive molecules present in each of the organic extracts, different extracts showed different inhibition zone diameters against the pathogens. Among the eight organic extracts used for the study, excellent inhibitory effects were shown by chloroform and methanol extracts. Conclusions: The present study indicates that green algae C. vulgaris is rich in natural compounds which are highly important in pharmacology and nutraceuticals. Although the presence of bioactive molecules is very less in the algae, excellent effect
Jain, Aanchal; Bhargava, Richa; Poddar, Pankaj, E-mail: email@example.com
In the present work, the physiological effects of the ZnO nanorods on the Gram positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Escherichia coli and Aerobacter aerogenes) bacterial cells have been studied. The analysis of bacterial growth curves for various concentrations of ZnO nanorods indicates that Gram positive and Gram negative bacterial cells show inhibition at concentrations of ∼ 64 and ∼ 256 μg/mL respectively. The marked difference in susceptibility towards nanorods was also validated by spread plate and disk diffusion methods. In addition, the scanning electron micrographs show a clear damage to the cells via changed morphology of the cells from rod to coccoid etc. The confocal optical microscopy images of these cells also demonstrate the reduction in live cell count in the presence of ZnO nanorods. These, results clearly indicate that the antibacterial activity of ZnO nanorods is higher towards Gram positive bacterium than Gram negative bacterium which indicates that the structure of the cell wall might play a major role in the interaction with nanostructured materials and shows high sensitivity to the particle concentration. Highlights: ► Effect of ZnO nanorods on the growth cycles of four bacterial strains. ► A relation has been established between growth rate of bacteria and concentration. ► Serious damage in the morphology of bacterial cells in the presence of ZnO nanorods. ► Microscopic studies to see the time dependent effect on bacterial cells.
Bolanle Kudirat Saliu
Full Text Available Nigerian locally produced cheese from milk, commonly known as wara is highly nutritious and highly prone to attack by spoilage and pathogenic microorganisms. Moist heat treatment and salting alone are the common methods used for processing. This study assessed the efficacy of these local processing methods in preserving the physicochemical properties and microbiological quality of wara. Samples were purchased from open markets in Ilorin; processed by boiling in water and with addition of salt; and stored at room temperature (28±2oC to mimic the local method. The samples were observed at 24 hrs interval for a period of 96 hrs, for changes in pH, color, odor and texture. Microbiological analysis was done following standard methods. The pH of most of the samples increased while the color, odor and texture deteriorated within 48 hrs of storage. The cheese samples were preserved most by boiling with salt. Many spoilage and pathogenic microorganisms were isolated. The bacterial isolates were Lactobaccillus acidophilus, Escherichia coli, Bacillus cereus, Staphylococcus aureus, Proteus vulgaris, Enterococcus feacalis, Aerobacter aerogenes, Klebsiella, Aerococcus, Micrococcus and Streptococcus spp.; while the fungi were Aspergillus flavus, A. fumigatus, A. flavus, Candida tropicalis, Rhizopus arrhizus, Penicillium and Mucor spp. Some of the microorganisms were eliminated during treatments, others survived while some contaminated the samples during storage. Though boiling of wara with salt was shown to improve its keeping quality compared to other methods studied, further treatments such as frying, drying, and roasting; as well as storage at low temperature may significantly increase the shelf life.
Adrelírio J. R. Gonçalves
Full Text Available São apresentados 31 casos de bacteremia por gram-negativos, assunto que vem merecendo muita atenção dos pesquisadores nos últimos anos. Os organismos etiológicos mais importantes que apareceram em igualdade de freqüência foram Escherichia coli e Klebsiella-Aerobacter, sendo responsáveis por 58% do total das infecções, seguidos por Pseudomonas. A porta de entrada mais freqüente foi o trato urinário em 61,3% dos casos. A infecção foi mais comum no sexo masculino e a faixa etária de 50 a 60 anos predominou. O uso prévio de antibióticos foi um fator predisponente muito importante, seguido pelo uso de esteróides e citostáticos. As principais doenças predisponentes foram diabetes mellitus e neoplasias malignas. Os principais fatores precipitantes foram a manipulação do aparelho urinário, com infecção prévia ou desencadeada, cirurgia do aparelho digestivo, uronatia obstrutiva e obstrução biliar. As principais manifestações clínicas foram a presença de febre, calafrios e hipotensão arterial. A complicação mais freqüente foi o choque bacteriano que incidiu em 58% dos casos, aproximadamente três vêzes aquela relatada na literatura. As outras foram a insuficiência renal aguda, superinfecção e infecção pulmonar metastática. Considerações terapêuticas gerais e esquemas de antibióticos são propostos para estes casos. A mortalidade da bacteremia simples foi de 30,7% e quando associada ao choque elevou-se para 72,2% . As infecções por Pseudomonas foram 100% fatais.
Objective to investigate clinical application value of infection prevention by drain continuous washing and vacuum suction of presacral rectal cancer anterior perineal region.Methods choose 87 cases rectal cancer patients with Miles surgery treated in Xinjiang Huazhong University of Science and Technology Bortala Prefecture People's Hospital Hubei Union Branch from January 2007 to November 2015, and carry on standard Miles operation through experimental and control group. Patients in experimental group were treated with presacral drainage tube and control group with pelvic and presacral drainage tube, examine materials by Chi-Square test. Results among 87 cases in study, 4 cases in experiment group occurred perineal incision infection, 11 cases in control group occurred perineal infection, difference between two groups showed statistical significance,P<0.05. Patient’s infection occurred in 3-14d after operation, and was located at presacral space. After dressing treatment, 2 cases developed chronic sinus surgery, which was resected by the second operation. Bacteria culture results of incision: 10 cases Escherichia coli, 2 cases Klebsiella pneumonia, 2 cases Aerobacter cloacae, 1 case Acinetobacter Bauman.Conclusion continuous drainage washing of presacral perineal region is simple and can effectively reduce infection rate of perineal region of rectal cancer.%目的：探讨直肠癌术后会阴区骶前引流管持续冲洗及负压吸引预防感染的临床应用价值。方法选取2007年1月到2015年11月新疆华中科技大学博州人民医院湖北协和分院收治87例行Miles手术直肠癌患者采用实验组和对照组，患者均行标准Miles手术治疗，实验组患者置骶前引流管，对照组使用盆腔、骶前引流管，进行检验，计数资料使用卡方检验，结果87例患者纳入研究，实验组术后4例患者发生会阴区切口感染，对照组11例发生会阴区感染，两组比较差异有统计学意义，P<0