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In the present study, we have constructed a bioluminescent bioreporter for the assessment of nitrate/nitrite bioavailability in wastewater. Specifically, an approximately 500-bp DNA fragment containing a nitrate/nitrite-activated... more
In the present study, we have constructed a bioluminescent bioreporter for the assessment of nitrate/nitrite bioavailability in wastewater. Specifically, an approximately 500-bp DNA fragment containing a nitrate/nitrite-activated nasR-like promoter (regulating expression of genes encoding nitrite reductase in the genus Klebsiella) was fused upstream of the Vibrio fischeri luxCDABE gene cassette in a modified mini-Tn5 vector. Characterization of this strain, designated W6-1, yielded dose-dependent increased bioluminescence coincident with increased nitrate, nitrite, and ammonium added to the growth medium from 1 to 11 ppm. Bioluminescence in response to nitrogen species addition was light dependent up to 10, 7, and 8 ppm with nitrate, nitrite, and ammonium, respectively. This response was linear in the range from 1 to 8 ppm for nitrate (R2 = 0.98), 1 to 6 ppm for nitrite (R2 = 0.99), and 1 to 7 ppm for ammonium (R2 = 0.99). A significant bioluminescent response was also recorded when strain W6-1 was incubated with slurries from aged, nitrate/nitrite contaminated wastewater. Thus, bioreporter strain W6-1 can be used to elucidate factors that constrain the use of nitrate/nitrite in wastewaters.
Research Interests: Microbiology, Chemistry, Technology, Medicine, Biological Sciences, and 15 moreMicrobiology and Biotechnology, Pubmed, Bacteria, Nitrates, Nitrate, Bioluminescence, Nitrite, Nitrate Reductase, Bioavailability, Nitrite Reductase, Quaternary Ammonium Compounds, Klebsiella Oxytoca, Nitrites, Aliivibrio fischeri, and LUX
Biosynthesis of biodegradable polymers polyhydroxyalkanotes (PHAs) have been studied extensively in wild type and genetically modified prokaryotic cells, however the content and structure of PHAs in wild type yeasts is not well... more
Biosynthesis of biodegradable polymers polyhydroxyalkanotes (PHAs) have been studied extensively in wild type and genetically modified prokaryotic cells, however the content and structure of PHAs in wild type yeasts is not well documented. The purpose of this study was to screen yeast isolates collected from different ecosystems for their ability to accumulate PHAs. Identification of the isolates and characterization of PHAs produced by the positive isolates were investigated. One positive isolate (strain Y4) was identified by both API20C system and 18S rDNA sequencing. The data revealed that isolate Y4 belongs to the yeast genus Rhodotorula and exhibits 18S rDNA similarity value >99% to the species Rhodotorula minuta. Quantification of PHAs yield of strain Y4 in glucose, oleic acid and tween 60 containing medium for over a growth period of 96 h gave 2% of PHAs in biomass. The nature of produced PHAs was analyzed by infrared spectroscopy and nuclear magnetic resonance (1H and 13C NMR) and found to contain polyhydroxybutyrate and polyhydroxyvalerate (PHBV).
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Disinfection of water and wastewater strongly contributes to solving the problem of water shortage in arid/semi-arid areas; cheap and ecofriendly approaches have to be used to meet water quality standards. In the present study, a green... more
Disinfection of water and wastewater strongly contributes to solving the problem of water shortage in arid/semi-arid areas; cheap and ecofriendly approaches have to be used to meet water quality standards. In the present study, a green synthesis of iron nanoparticles (INPs) under aerobic and anaerobic conditions via nitrate reductases (NAP/NAR) enzymes produced by Proteus mirabilis strain 10B were employed for this target. The biosynthesized INPs were characterized; UV-Vis spectroscopy revealed surface plasmon resonance at 410 (aerobic) and 265 nm (anaerobic). XRD indicated crystalline magnetite ((MNPs) aerobically synthesized) and zerovalent INPs (ZVINPs anaerobically synthesized). EDX demonstrated strong iron signal with atomic percentages 73.3% (MNPs) and 61.7% (ZVINPs). TEM micrographs illustrated tiny, spherical, periplasmic MNPs (1.44–1.92 nm) and cytoplasmic ZVINPs with 11.7–60.8 nm. Zeta potential recorded − 31.8 mV (ZVINPs) and − 66.4 mV (MNPs) affirming colloidal stability. Moreover, the disinfection power of INPs was evaluated for standards organisms and real water (fresh, sea and salt mine) and wastewater (municipal, agricultural and industrial) samples. The results reported that INPs displayed higher antagonistic effect than iron precursor, 700 and 850 μg/mL of MNPs and ZVINPs, respectively, was sufficient to show a drastic algicidal effect on algal growth. Both types of INPs demonstrated obvious dose-dependent antibiofilm efficiency. Due to their smaller size, MNPs were more efficient than ZVINPs at the suppression of microbial growth in all examined water samples. Overall, MNPs showed superior antagonistic activity, which promotes their exploitation in enhancing water/wastewater quality.
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Research Interests: Chemistry, In Vitro, Biopolymer, Silk, Antioxidant, and 5 moreRSC, Antimicrobial, DPPH, Sericin, and ABTS
Abstract This study deals with 16S-rDNA identified bacteria, Lysinibacillus sp., Raoultella sp., and Streptomyces sp. capable of precipitating CaCO3 through nitrate reduction aerobically and anaerobically. The produced CaCO3 crystals were... more
Abstract This study deals with 16S-rDNA identified bacteria, Lysinibacillus sp., Raoultella sp., and Streptomyces sp. capable of precipitating CaCO3 through nitrate reduction aerobically and anaerobically. The produced CaCO3 crystals were analyzed using XRD, EDX, FTIR, TGA and SEM. The results showed that the carbonatogenic bacteria served as nucleation sites for CaCO3 precipitation with distinct variation in polymorph and morphology; reflecting strain-specific property. Notably, the amount of precipitated CaCO3 recorded 3.27 (aerobic), 1.55 (anaerobic), 4.15 (aerobic), 3.75 (aerobic) and 1.87 (anaerobic) g/100 mL of strains Lysinibacillus sp., Streptomyces sp. and Raoultella sp., respectively, after 240 h of incubation. The study of changes in media chemistry during carbonatogenesis process revealed positive correlation between bacterial growth, nitrate reductase activity, pH, EC, Ca2+ depletion, amount of deposited CaCO3 and NO3 − consumption. Therefore, the applications of these bacterial strains, which were employed for the first time in carbonatogenesis process, are promising in the environmental, biomedical and civil engineering fields.
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Research Interests: Biology, Industrial Biotechnology, Medicine, Industrial, Oxidoreductases, and 12 moreBioluminescence, Phenol, Contaminated soil, Vibrio, Substrate Specificity, Acinetobacter, Food Sciences, Base Sequence, INDUSTRIAL MICROBIOLOGY AND BIOTECHNOLOGY, Vibrio Fischeri, Soil Pollutants, and Molecular Sequence Data
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Research Interests: Biochemistry, Ecotoxicology, Nuclear Magnetic Resonance, Biology, Metabolic Engineering, and 10 moreMultidisciplinary, Environmental science and technology, Saccharomyces cerevisiae, Yeast, Biosynthesis, Western blot, Repetitive Strain Injury, Polyhydroxyalkanoates, Polyhydroxybutyrate, and Cupriavidus necator
This study employed the ureolytic fungal Metschnikowia pulcherrima (29A) and bacterial Raoultella planticola (VIP) strains in Pb 2+ and Hg 2+ removal using the promising CaCO 3 bio precipitation technique. Out of fifty isolates, strains... more
This study employed the ureolytic fungal Metschnikowia pulcherrima (29A) and bacterial Raoultella planticola (VIP) strains in Pb 2+ and Hg 2+ removal using the promising CaCO 3 bio precipitation technique. Out of fifty isolates, strains 29A and VIP were selected based on their highest ureolytic activity followed by MIC assay using 350 ppm of Pb 2+ and Hg 2+ . The maximum urease activity recorded 884 and 639 U/mL for 29A and VIP strains at 24 and 30h of incubation, respectively. Complete removal of Pb 2+ was achieved at 42h and 90h for 29A, VIP correspondingly, while Hg 2+ was totally removed at 60h and 102h for 29A, VIP respectively. Remarkable removal of Ca 2+ (>95%) was achieved by the end of the experiments, which would address the hardness problem in the water treatment process. Further, EDX, SEM and, XRD were used to characterize the remediated precipitates. EDX profiles showed characteristic peaks of C, O and, Ca 2+ besides Pb 2+ and Hg 2+ . SEM illustrated the presence of ...
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Bacterial polymeric silk is produced by Bacillus sp. strain NE and is composed of two proteins, called fibroin and sericin, with several biomedical and biotechnological applications. In the current study and for the first time, the whole... more
Bacterial polymeric silk is produced by Bacillus sp. strain NE and is composed of two proteins, called fibroin and sericin, with several biomedical and biotechnological applications. In the current study and for the first time, the whole bacterial silk proteins were found capable of exerting antiviral effects against herpes simplex virus type-1 (HSV-1), adenovirus type 7 (AD7), and hepatitis C virus (HCV). The direct interaction between bacterial silk-like proteins and both HSV-1 and AD7 showed potent inhibitory activity against viral entry with IC50 values determined to be 4.1 and 46.4 μg/mL of protein, respectively. The adsorption inhibitory activity of the bacterial silk proteins showed a blocking activity against HSV-1 and AD7 with IC50 values determined to be 12.5 and 222.4 ± 1.0 μg/mL, respectively. However, the bacterial silk proteins exhibited an inhibitory effect on HSV-1 and AD7 replication inside infected cells with IC50 values of 9.8 and 109.3 μg/mL, respectively. All th...
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Abstract Recombinant bioluminescent bacteria are frequently directed towards use as environmental biosensors because it has high sensitivity, selectivity, costless, easy to use and function as rapid measurement to detect heavy metals. The... more
Abstract Recombinant bioluminescent bacteria are frequently directed towards use as environmental biosensors because it has high sensitivity, selectivity, costless, easy to use and function as rapid measurement to detect heavy metals. The bioluminescence of DF4/PUTK2 assay is based on using the bio-reporter Acinetobacter DF4/PUTK2 carrying luciferase genes luxCDABE which emit light constitutively. This can be measured in time intervals by luminometer to determine the behavior of bio-reporter against lead. The light emitted in the lead treated samples was equal or increased than the control. Therefore, the bio-reporter DF4/PUTK2 was subjected to intensive studies to elucidate its behavior with lead and if it was possible to be employed as a lead light-on assay in water in reverse order. Time exposure (5 to 990 min), lead concentration (0 to 30000 ppm), and lead salts (acetate-chloride and nitrate) were included in this study. The bio-reporter DF4/PUTK2 was more sensitive to lead concentrations range (19.25 to 15000 ppm). However, at high concentrations of lead, the light was being decreased due to cell death and/or metabolic burden simultaneously. It was possible to detect the presence of lead in water samples through light-induction in specific concentrations which add another advantage to the bio-reporter DF4/PUTK2.
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BACKGROUNDThe recalcitrant nature of lead (Pb) and mercury (Hg) to degradation represents a real risk to living creatures and their surrounding ecosystems. Therefore, this study employed ureolytic fungal strain Metschnikowia pulcherrima... more
BACKGROUNDThe recalcitrant nature of lead (Pb) and mercury (Hg) to degradation represents a real risk to living creatures and their surrounding ecosystems. Therefore, this study employed ureolytic fungal strain Metschnikowia pulcherrima (29A) and bacterial strain Raoultella planticola (VIP) in their removal using the promising CaCO3 bioprecipitation technique, for the first time.RESULTSOut of 50 isolates, strains 29A and VIP were selected based on their highest ureolytic activity, followed by minimum inhibitory concentration assay using 350 ppm of Pb2+ and Hg2+. Throughout 7 days of incubation at 30 °C and 150 rpm with 108 CFU mL−1 inoculum, the maximum urease activity was 884 and 639 U mL−1 for 29A and VIP at 24 and 30 h of incubation, respectively. Complete removal of Pb2+ was achieved at 42 h (29A) and 90 h (VIP), while Hg2+ was totally removed at 60 h (29A) and 102 h (VIP). Remarkable removal of Ca2+ (>95%) was achieved by the end of the experiments, which would address the h...
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The quest for eco-friendly and biocompatible nanoparticles (NPs) is an urgent issue in the agenda of the scientific community and applied technology, which compressing synthesis routes. For the first time, a simple route for the... more
The quest for eco-friendly and biocompatible nanoparticles (NPs) is an urgent issue in the agenda of the scientific community and applied technology, which compressing synthesis routes. For the first time, a simple route for the biosynthesis of functionalized CuFe-hybrid nanocomposites (FCFNCs) was achieved using Streptomyces cyaneofuscatus through a simultaneous bioreduction strategy of Cu and Fe salts. The suitability of FCFNCs was evaluated medically and environmentally as an anticancer agent, antimicrobial agent and dye bio-sorbent. The physicochemical characteristics of FCFNCs using XRD, EDX, elemental mapping, FTIR, UV–Vis., TEM and ζ-potential confirmed the formation of spheres agglomerated into chains (37 ± 2.2 nm), self-functionalized nanocomposite by proteinaceous moieties with considerable stability (− 26.2 mV). As an anticancer agent, FCFNCs displayed the highest apoptotic impact (> 77.7%) on Caco-2, HepG-2, MCF-7 and PC-3 cancer cells at IC50 ≤ 17.21 μg/mL with the m...
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Natural environment is a wealthy source of bionanofactories that invested in green approaches as the fabrication of biomimetic nanomaterials. The current study points out the importance of microbial activity in metal bioremediation, green... more
Natural environment is a wealthy source of bionanofactories that invested in green approaches as the fabrication of biomimetic nanomaterials. The current study points out the importance of microbial activity in metal bioremediation, green synthesis of NPs, and global biogeochemical cycles of bioactive metals as well. It describes for the first time the synchronous biosynthesis of zero- (intracellular) and one-dimensional (extracellular) copper oxide nanoparticles (CuO-NPs) viaProteus mirabilis10B. This bionanofactory represents key location of reduction and stabilization, and its exopolysaccharide additionally provides nucleation and growth site for CuO-NPs. The as-synthesized CuO-NPs were characterized; UV-Vis spectroscopy revealed surface plasmon resonance at 275 and 430 nm for intracellular and extracellular CuO-NPs, respectively. XRD reflected crystalline, pure phase monoclinic structure CuO-NPs. EDX illustrated strong copper signal with atomic percentages 32.3% (intracellular) ...
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The nonbiodegradability nature of heavy metals renders them resident in food chain and subsequently, destructing the entire ecosystem. Therefore, this study aimed to employ nitrate reduction-driven calcium carbonate precipitation in... more
The nonbiodegradability nature of heavy metals renders them resident in food chain and subsequently, destructing the entire ecosystem. Therefore, this study aimed to employ nitrate reduction-driven calcium carbonate precipitation in remediation of lead and mercury aerobically and anaerobically by Proteus mirabilis 10B, for the first time. Initially, Plackett-Burman design was employed to screen of 16 independent variables for their significances on periplasmic (NAP) and membrane-bound (NAR) nitrate reductases. The levels for five significant variables and their interaction effects were further optimized by central composite design. The maximum activities of NAP and NAR recorded 2450 and 3050 U/mL by 2-fold enhancement, comparing with non-optimized medium. Under aerobic and anaerobic optimized remediation conditions, the changes in media chemistry revealed positive correlation among bacterial growth, nitrate reductase activity, pH, NO3− and NO2− consumption and removal of Ca2+, Pb2+ ...
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The development of environmentally benign procedures for the synthesis of metallic nanoparticles (NPs) is a vital aspect in bionanotechnology applications for health care and the environment. This study describes the biosynthesis of Ag,... more
The development of environmentally benign procedures for the synthesis of metallic nanoparticles (NPs) is a vital aspect in bionanotechnology applications for health care and the environment. This study describes the biosynthesis of Ag, Co, Ni, and Zn NPs by employing nanobiofactory Proteus mirabilis strain 10B. The physicochemical characterization UV-visible spectroscopy, scanning electron microscopy-energy-dispersive X-ray microanalysis (EDX), X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS) technique including ζ potential, and polydispersity index (PDI) confirmed the formation of pure, stable monodisperse quasi-spherical oxide NPs of corresponding metals. The antimicrobial activity of biofabricated NPs was assessed against Gram-negative and Gram-positive bacteria, biofilm, yeast, mold, and algae via a well diffusion method. The results displayed significant antagonistic activity in comparison to their bulk and commercial ant...
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Recently, the wild type yeast Kloeckera sp. strain KY1 was equipped in their cytoplasm with the phaABC operon containing genes phbA, phbB and phbC of the PHA biosynthetic pathway of Ralstonia eutropha. Unpredicted, resulted transgenic... more
Recently, the wild type yeast Kloeckera sp. strain KY1 was equipped in their cytoplasm with the phaABC operon containing genes phbA, phbB and phbC of the PHA biosynthetic pathway of Ralstonia eutropha. Unpredicted, resulted transgenic yeast strain KY1/PHA was able to synthesize another exopolymer beside the production of PHA. Subsequently, produced exopolymer was subject for further identification, characterization and analysis. Partial purification of exopolymer was performed and characterized as glycoprotein. HPLC analysis of the polymer revealed the presence of a fructose chain. The functional group analysis by FT-IR spectroscopy showed the presence of carboxyl, hydroxyl and amid groups. The exopolymer was soluble in water and insoluble in any tested organic solvents and could flocculate kaolin suspension (5 g/l) over a wide range of pH (pH 3 to 9) and temperature (5 to 50°C) tested in the presence of CaCl 2. The highest flocculation activity of 99% for kaolin suspension was achi...
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AIM: Aim of this study was to examine the effectiveness of body acupuncture on body weight loss, routine laboratory tests and pro-inflammatory markers.METHODOLOGY: The study was performed on eighty obese patients. They were divided into... more
AIM: Aim of this study was to examine the effectiveness of body acupuncture on body weight loss, routine laboratory tests and pro-inflammatory markers.METHODOLOGY: The study was performed on eighty obese patients. They were divided into three groups according to their body mass index. Subjects received acupuncture for three- six months in combination with a low-calorie diet. They were assessed pre and post acupuncture, by anthropometric measurement, routine laboratory tests and, tumor necrosis factor- alpha (TNF-α), interleukin- 6 (IL-6), and high sensitivity C-reactive protein (hsCRP) levels in serum.RESULTS: The pre-acupuncture results showed significant difference between the three grades of obesity and the controls regarding TNFα, IL-6 and hsCRP. We found significant reduction in anthropometric measurement of adiposity after acupuncture. In comparing the pre &post acupuncture results of TNF-α, IL-6 and hsCRP showed high significant reduction after acupuncture. There are highl...
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Out of 23 symptomatic cases 21 specimens were positive for T. vaginalis by one or more methods. 21 were positive by PCR (91.3%) and 17 (72.9%) by culture, 14 (60.8%) by Acridine orange (AO) stain and 13 (56.5%) by wet mount microscopy.... more
Out of 23 symptomatic cases 21 specimens were positive for T. vaginalis by one or more methods. 21 were positive by PCR (91.3%) and 17 (72.9%) by culture, 14 (60.8%) by Acridine orange (AO) stain and 13 (56.5%) by wet mount microscopy. The PCR detected all the positive cases and no PCR negative cases proved to be positive by any other technique. So, it is the test of choice for diagnosis of trichomoniasis. The modified Diamond's media proved to be highly sensitive (80.95%) and the results of the culture were significantly associated with those of PCR. The results of both wet mount and AO stain were insignificantly associated. The wet mount although widely used, easy, rapid and inexpensive yet, it has low sensitivity. So, negative cases should be repeated by either culture or PCR.
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The restriction fragment length polymorphism (PCR-RFLP) of 18S rDNA amplified fragments, was conducted to recognize between an unidentified Leishmania isolated from Egyptian patient infected in Saudi Arabia and two L. major reference... more
The restriction fragment length polymorphism (PCR-RFLP) of 18S rDNA amplified fragments, was conducted to recognize between an unidentified Leishmania isolated from Egyptian patient infected in Saudi Arabia and two L. major reference strains causing cutaneous lesions. The strains were maintained both in vivo & in vitro. Additional requirement as morphological characterization on basis of the light microscope & scanning electron microscopy and behaviour in experimental Swiss albino mice regarding development of lesions were performed. The results showed that, PCR-RFLP analysis of the 18S rDNA amplified PCR fragments was highly successful to put the unidentified Leishmania strain in the category of L. major. There was no significant differences regarding the cutaneous lesions development. In spite of the significant variations of the morphometric measurements of the three strains were observed.
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In the present study, we have constructed a bioluminescent bioreporter for the assessment of nitrate/nitrite bioavailability in wastewater. Specifically, an approximately 500-bp DNA fragment containing a nitrate/nitrite-activated... more
In the present study, we have constructed a bioluminescent bioreporter for the assessment of nitrate/nitrite bioavailability in wastewater. Specifically, an approximately 500-bp DNA fragment containing a nitrate/nitrite-activated nasR-like promoter (regulating expression of genes encoding nitrite reductase in the genus Klebsiella) was fused upstream of the Vibrio fischeri luxCDABE gene cassette in a modified mini-Tn5 vector. Characterization of this strain, designated W6-1, yielded dose-dependent increased bioluminescence coincident with increased nitrate, nitrite, and ammonium added to the growth medium from 1 to 11 ppm. Bioluminescence in response to nitrogen species addition was light dependent up to 10, 7, and 8 ppm with nitrate, nitrite, and ammonium, respectively. This response was linear in the range from 1 to 8 ppm for nitrate (R2 = 0.98), 1 to 6 ppm for nitrite (R2 = 0.99), and 1 to 7 ppm for ammonium (R2 = 0.99). A significant bioluminescent response was also recorded when...