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1.
Article in English | MEDLINE | ID: mdl-38842700

ABSTRACT

RATIONALE: Evidence of the effects of chronic caffeine (CAFF)-containing beverages, alone or in combination with agomelatine (AGO) or quetiapine (QUET), on electroencephalography (EEG), which is relevant to cognition, epileptogenesis, and ovarian function, remains lacking. Estrogenic, adenosinergic, and melatonergic signaling is possibly linked to the dynamics of these substances. OBJECTIVES: The brain and ovarian effects of CAFF were compared with those of AGO + CAFF and QUET + CAFF. The implications of estrogenic, adenosinergic, and melatonergic signaling and the brain-ovarian crosstalk were investigated. METHODS: Adult female rats were administered AGO (10 mg/kg), QUET (10 mg/kg), CAFF, AGO + CAFF, or QUET + CAFF, once daily for 8 weeks. EEG, estrous cycle progression, and microstructure of the brain and ovaries were examined. Brain and ovarian 17ß-estradiol (E2), antimullerian hormone (AMH), estrogen receptor alpha (E2Rα), adenosine receptor 2A (A2AR), and melatonin receptor 2 (MT2R) were assessed. RESULTS: CAFF, alone or combined with AGO or QUET, reduced the maximum EEG peak, which was positively linked to ovarian E2Rα, negatively correlated to cortical neurodegeneration and ovarian MT2R, and associated with cystic ovaries. A large corpus luteum emerged with AGO + CAFF and QUET + CAFF, antagonizing the CAFF-mediated increased ovarian A2AR and reduced cortical E2Rα. AGO + CAFF provoked TTP delay and increased ovarian AMH, while QUET + CAFF slowed source EEG frequency to δ range and increased brain E2. CONCLUSIONS: CAFF treatment triggered brain and ovarian derangements partially antagonized with concurrent AGO or QUET administration but with no overt affection of estrus cycle progression. Estrogenic, adenosinergic, and melatonergic signaling and brain-ovarian crosstalk may explain these effects.

2.
Chemosphere ; 356: 141899, 2024 May.
Article in English | MEDLINE | ID: mdl-38579952

ABSTRACT

Although the neonicotinoid insecticides have good selectivity towards insects rather than vertebrates, they have severe effects on honeybee production and pollination activities. Therefore, the effects of imidacloprid (IMI), the most used neonicotinoid, on the two main bioreceptors, acetylcholinesterase (AChE) and nicotinic acetylcholine receptor alpha subunit (nAChRα1) of honeybees were examined to identify their roles in honeybee toxicity and possible binding sites which assist in selecting and designing neonicotinoids. In vivo, IMI showed a high inhibitory effect on AChE (IC50 5.63 mg/L); however, the effect was much lower in vitro experiment (IC50 719 mg/L). This result induced us to examine the IMI effect on AChE gene expression which revealed that the AChE-2 gene expression was severely affected by IMI explaining the observed high enzyme inhibition. In addition, although toxicity increased by increasing exposure to IMI (LC50 2.9 mg/L after 4h and 0.75 mg/L after 48h), AChE was not elevated (IC50 5.63 and 5.52 mg/L respectively). Besides, Despite resuming most enzyme activity (77% during 2 h and 84.14% after 4 h), a high mortality level was observed with LC50 2.9 mg/L. These results reinforced that the observed high toxicity is a multifactor process. Accordingly, Molecular modeling and docking of IMI into honeybee AChE and nAChRα1were also performed to examine their possible interactions and identify the important binding sites. Results models indicated that the first two binding sites in AChE were found in the esteratic subunit in the active site explaining the observed in vitro inhibition. In nAChRα1, four of the highest five free energy binding sites are located in the large TM3-TM4 loop and one in the extracellular loops. Consequently, the present work revealed that IMI toxicity is attributed to various factors including direct interaction with both AChE and nAChRα1 as well as downregulating AChE-2 gene expression.


Subject(s)
Acetylcholinesterase , Insecticides , Neonicotinoids , Nitro Compounds , Receptors, Nicotinic , Animals , Acetylcholinesterase/metabolism , Bees/drug effects , Neonicotinoids/toxicity , Receptors, Nicotinic/metabolism , Nitro Compounds/toxicity , Insecticides/toxicity , Molecular Docking Simulation , Models, Molecular , Binding Sites , Insect Proteins/metabolism , Insect Proteins/genetics
3.
Oxid Med Cell Longev ; 2021: 9482529, 2021.
Article in English | MEDLINE | ID: mdl-34754366

ABSTRACT

The current work was aimed at evaluating the ameliorative role of quercetin (QR) on the possible toxicity of Red Bull energy drink (RB-Ed) in the cerebral cortex of rats. To achieve the goal, the rats were allocated into 4 groups. The first group received distilled water as control. Groups II and III were given Red Bull energy drink alone and in combination with quercetin, respectively. The fourth group served as recovery to group II. The experimental duration was four weeks for all groups whereas the recovery period of group IV was two weeks. QR upregulated the mRNA and protein expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) genes, which can protect against RB-Ed neurotoxicity. Moreover, by reducing the thiobarbituric acid reactive substance and increasing the total antioxidant capacity levels, QR protected rats' cerebral cortex against Red Bull energy drink-induced oxidative damage. Quercetin also inhibited RB-Ed-induced histomorphological degeneration which was confirmed by the increase in the intact neurons and the rise in the neuron-specific enolase immunoreaction. QR increased the reduction of the brain-derived neurotrophic factor that was elicited by RB-Ed and acts as an anti-inflammatory agent by reducing the proinflammatory marker, interleukin 1 beta and DNA damage markers, heat shock protein 70, and 8-hydroxydeoxyguanosine. It could be concluded that the alleviating impacts of QR on RB-Ed neurotoxicity in rats could be related to the modulation of Nrf2 and HO-1 which in turn affects the redox status.


Subject(s)
Cerebral Cortex/drug effects , Energy Drinks/toxicity , Heme Oxygenase (Decyclizing)/metabolism , NF-E2-Related Factor 2/metabolism , Neuroprotective Agents/pharmacology , Neurotoxicity Syndromes/prevention & control , Quercetin/pharmacology , Animals , Antioxidants/pharmacology , Caffeine/toxicity , Central Nervous System Stimulants/toxicity , Cerebral Cortex/metabolism , Cerebral Cortex/pathology , Heme Oxygenase (Decyclizing)/genetics , Male , NF-E2-Related Factor 2/genetics , Neurotoxicity Syndromes/etiology , Neurotoxicity Syndromes/metabolism , Neurotoxicity Syndromes/pathology , Oxidative Stress , Rats , Rats, Wistar
4.
J Med Microbiol ; 70(10)2021 Oct.
Article in English | MEDLINE | ID: mdl-34612810

ABSTRACT

Introduction. The emergence of multidrug-resistant Salmonella Typhimurium strains has increased the need for safe, alternative therapies from natural sources with antibacterial properties.Hypothesis/Gap Statement. There are no published data regarding the use of chitosan propolis nanocomposite (CPNP) either alone or in combination with antibiotics as antimicrobials against S. Typhimurium, especially in Egypt.Aim. This study evaluated the antibacterial activities of five antimicrobials [apramycin, propolis, chitosan nanoparticles (CNPs), chitosan propolis nanocomposite (CPNP) and CPNP +apramycin] against ten virulent and multidrug-resistant (MDR) S. Typhimurium field strains recovered from diarrheic rabbits through in vitro and in vivo study.Methodology. The expression levels of three virulence genes of S. Typhimurium strains were determined by quantitative reverse-transcription PCR (RT-qPCR) after exposure to sub-inhibitory concentrations of apramycin, propolis, CNPs, CPNP alone, and CPNP +apramycin. Additionally, 90 New Zealand rabbits were divided into control and experimentally S. Typhimurium-infected groups. The infected rabbits were orally administered saline solution (infected-untreated); 10 mg apramycin/kg (infected-apramycin-treated); 50 mg propolis/kg (infected-propolis-treated); 15 mg CPNP/kg (infected-CPNP-treated) and 15 mg CPNP +10 mg apramycin/kg (infected-CPNP +apramycin-treated) for 5 days.Results. The RT-qPCR analysis revealed different degrees of downregulation of all screened genes. Furthermore, the treatment of infected rabbits with CPNP or CPNP +apramycin significantly improved performance parameters, and total bacterial and Salmonella species counts, while also modulating both oxidative stress and altered liver and kidney parameters.Conclusion. This work demonstrates the use of CPNP alone or in combination with apramycin in the treatment of S. Typhimurium in rabbits.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Chitosan/chemistry , Drug Resistance, Multiple, Bacterial/drug effects , Nanocomposites/therapeutic use , Propolis/chemistry , Salmonella Infections/drug therapy , Salmonella typhimurium/drug effects , Animals , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Antioxidants/metabolism , Bacterial Load/drug effects , Cell Survival/drug effects , Chitosan/pharmacology , Chitosan/therapeutic use , Chlorocebus aethiops , Drug Resistance, Multiple, Bacterial/genetics , Gene Expression Regulation, Bacterial/drug effects , Microbial Sensitivity Tests , Nanocomposites/chemistry , Nebramycin/analogs & derivatives , Nebramycin/pharmacology , Nebramycin/therapeutic use , Propolis/pharmacology , Propolis/therapeutic use , Rabbits , Salmonella Infections/microbiology , Salmonella typhimurium/pathogenicity , Vero Cells , Virulence/genetics
5.
Cell Tissue Res ; 385(1): 223-238, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33791879

ABSTRACT

This study was conducted on forty adult rats divided into four groups: Group I (control) that is divided into subgroups A, B, and C and Group II (methotrexate (MTX)-treated); the rats were injected intraperitoneally with MTX at a dose of 1 mg/kg/week, for 8 weeks. Group III (MTX-Se co-treated) was injected with MTX like Group II plus an oral administration of selenium at a dose of 10 µg/kg b.w/day, for 8 weeks. Group IV (MTX-PRP co-treated), rats were injected intraperitoneally with MTX like Group II plus platelet-rich plasma (PRP) injection under the scrotum, three times with 2-week intervals (volume-0.1 ml per injection) and euthanized after 8 weeks. Histological, immunohistochemical, and genetic expression using qPCR and western blotting technique were conducted. There was improvement in histological structure of testes in most specimens of Group IV. The latter group revealed a significant decrease in Bax and an increase in Bcl-2. The regeneration of testicular tissue was more observed in Group IV as measured by an increase in mean number of PCNA. Moreover, Group IV revealed an increased genetic level of FSCN3, GCNF, UBQLN3, and DAZL. Both MTX-Se and MTX-PRP have an anti-inflammatory effect as measured by a reduction in NF-κb. The anti-oxidative effect of selenium and PRP was noticed by a decrease in the level of the iNos and an increase in eNos protein and the autophagy marker LC3. PRP has ameliorative effects on induced rat testicular toxicity as evaluated by morphological changes and confirmed by immunohistochemical reactions, genetic expression, and western blotting analyses including oxidative and anti- oxidative markers.


Subject(s)
Immunohistochemistry/methods , Platelet-Rich Plasma/metabolism , Selenium/therapeutic use , Testis/drug effects , Animals , Male , Rats , Selenium/pharmacology
6.
Sci Rep ; 10(1): 8840, 2020 06 01.
Article in English | MEDLINE | ID: mdl-32483368

ABSTRACT

Aging causes morphological and functional changes in the cerebellum. This work aimed to demonstrate the implication of JAK1/STAT3/SOCS3 on aging-induced changes of rat cerebellum. Thirty male rats were divided into: adult (12 months), early senile (24 months) and late senile (32 months) groups. Immunohistochemical reaction of the cerebellum to GFAP and caspase-3 was assessed and the expression of JAK1, STAT3, SOCS3 proteins was also evaluated. TNFα as well as the activities of malondialdehyde (MDA) and reduced glutathione (GSH) in cerebellar tissue were also measured. The cerebellum of late senile rats revealed more degenerative changes than early senile rats in the form of increase in GFAP and caspase-3 immunoreaction. Additionally, there was decrease in JAK1and STAT3 expression in early and late senile rats and increase in SOCS3 when compare early and late senile groups with adult one. Enhancement of TNFα was noticed with aging as well as significant decrease in GSH and increase in MDA in early senile group. Moreover, late senile group revealed significant decrease in GSH and increase in MDA. It could be concluded that aging resulting in variable changes of the cerebellum as detected by morphological changes, immunohistochemical reactions of caspase-3 and GFAP and expression of JAK1/STAT3/SOCS3 proteins. Additionally, inflammatory marker TNFα and the activity of oxidative/antioxidative stress markers; malondialdehyde (MDA) and reduced glutathione (GSH) were also affected with aging.


Subject(s)
Aging , Cerebellum/metabolism , Janus Kinase 1/metabolism , STAT3 Transcription Factor/metabolism , Suppressor of Cytokine Signaling 3 Protein/metabolism , Animals , Caspase 3/metabolism , Cerebellum/pathology , Glial Fibrillary Acidic Protein/metabolism , Glutathione/metabolism , Immunohistochemistry , Male , Malondialdehyde/metabolism , Microscopy, Electron , Rats , Rats, Wistar , Signal Transduction , Tumor Necrosis Factor-alpha/metabolism
7.
Eur. j. anat ; 23(3): 201-213, mayo 2019. ilus, graf, tab
Article in English | IBECS | ID: ibc-182981

ABSTRACT

Cisplatin is a potent chemotherapeutic agent used to treat a variety of cancers such as ovarian, uterine, and bladder. The major limiting side effect of cisplatin is its hepatotoxicity. The possible mechanism of cisplatin hepatotoxicity was due to the affection of oxidant-antioxidant system. Platelet-rich plasma (PRP) has a powerful therapeutic option for its ability to deliver a great variety of biologically active GFs to the site of injury. PRP has grown as an attractive biologic instrument in regenerative medicine for its powerful healing properties. It is considered as a source of growth factors that may induce tissue repairing and improve fibrosis. This product has proven its efficacy in multiple studies, but its effect on cisplatin-induced hepatotoxicity has not yet been elucidated. The present study was designed to analyze the therapeutic role of PRP in cisplatin-induced hepatotoxicity. 30 adult male adult male albino rats were used in the present study divided into 3 groups (control group, cisplatin-treated group and PRP-treated group). By the end of the experimental period, blood samples were collected for measurement of serum AST, ALT and ALP enzymes; then the rats were sacrificed by cervical dislocation. Fresh liver parts were used to measure the oxidative markers in liver homogenates, while other parts were processed and subjected for histopathological and histomorphometric and immunohistochemical analyses for VEGF, Caspase 3 expression of the different experimental groups. The statistical study was done for the resultant data. Group II (Cisplatin-treated group) showed marked pathological hepatic changes; loss of architecture, congested dilated sinusoids lined by darkly stained pyknotic Kupffer cells; and hepatocytes nuclei were pyknotic and karyolitic. Dilated congested portal vein, interstitial acidophilic exudate, marked polymorphic cellular infiltration. There were increased collagen fibers deposition, a weak positive PAS reaction, strong positive caspase 3 reactions and strong positive VEGF reaction. Also, there were a marked increase in hepatic enzymes, MDA levels and a marked decrease in GSH level. Treatment with PRP in Group III revealed improvement of the hepatic parenchymal architecture with strong PAS reaction and minimal collagen fibers deposition. Weak positive caspase immunoreaction and strong positive VEGF reaction were noticed. Also, there was a marked improvement in the parameter of hepatic enzymes, MDA and GSH level comparable with the control group. It is concluded that PRP could ameliorate the liver against cisplatin-induced hepatotoxicity


No disponible


Subject(s)
Animals , Rats , Therapeutics , Platelet-Rich Plasma/chemistry , Cisplatin/toxicity , Apoptotic Protease-Activating Factor 1/toxicity , Caspase 3/toxicity , Apoptotic Protease-Activating Factor 1/adverse effects , Platelet-Rich Plasma/enzymology , Immunohistochemistry , Receptors, Vascular Endothelial Growth Factor/administration & dosage , Research Design , Liver/chemistry , Liver/enzymology , Biomarkers , Analysis of Variance
8.
J Cosmet Dermatol ; 18(1): 107-114, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30548170

ABSTRACT

BACKGROUND: Many methods have been performed to achieve a satisfying outcome in acne scars but some of them were high cost and also were associated with low results and some complications. OBJECTIVES: To evaluate and compare the efficacy and safety therapy of glycolic acid (GA) peel, microneedling with dermapen and a combination of both procedures in treatment of atrophic acne scars. PATENTS AND METHODS: This study was conducted on 30 patients suffering from acne scars. They were randomly assigned into three groups, each group included 10 patients; group I was treated with GA peel, group II treated was with microneedling. Group III received a combination of both procedures. All patients received six sessions with 2-week intervals. The clinical assessment was based on the qualitative global scar grading system before and after treatment, quartile grading scale, and degree of patient satisfaction. RESULTS: There was a statistically significant decrease in acne scars grade after treatment among the studied groups (P = 0.04) but it was higher in group III. There was improvement in boxcar, ice pick, and rolling scars in all groups, respectively (P = 0.03, P = 0.04, P = 0.04). Patients' satisfaction was higher in group III (P = 0.04). CONCLUSION: The combination of dermapen and GA peel is more effective than monotherapy.


Subject(s)
Cicatrix/therapy , Cosmetic Techniques/instrumentation , Glycolates/therapeutic use , Keratolytic Agents/therapeutic use , Needles , Acne Vulgaris/complications , Adult , Chemexfoliation , Cicatrix/etiology , Combined Modality Therapy , Female , Humans , Male , Middle Aged , Patient Satisfaction , Random Allocation , Severity of Illness Index , Young Adult
9.
Acta Histochem ; 120(5): 490-503, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29871770

ABSTRACT

Diabetes mellitus (DM) is a chronic metabolic disease in which the body fails to produce enough insulin or increased tissue resistance to insulin. The diabetes may have profound effects on placental development and function. This study was designed to detect the placental changes in pregnancy associated with DM comparing these changes with normal placenta. The study was carried out on sixty full-term placentae; divided into three equal groups; control group (group I): placentae of normal pregnancy, uncontrolled diabetes (group II): placentae from pregnant women whose blood glucose is poorly controlled during pregnancy. Controlled diabetes (group III): includes placentae from diabetic women whose blood glucose is controlled during pregnancy. The placentae from group II tend to be heavier and exhibited immaturity of villi, villous edema, fibrosis, excessive syncytial knots formation and infarctions. In addition to, fibrinoid necrosis, increased thickness of vasculosyncytial membrane, syncytial basement membrane, microvillous abnormalities and vascular endothelial changes were demonstrated. The syncytial multivesicular knots were present in placentae of group II. The nuclei within these syncytial knots display condensed chromatin, either dispersed throughout the nucleus or in the form of dense peripheral clumps with and numerous cytoplasmic vacuoles. The syncytial basement membrane showed focal areas of increase in its thickness and irregularity. Villous cytotrophoblasts showed increased number and activity in the form of numerous secretory granules, abundant dilated RER, larger distorted mitochondria. Villous vessels showed various degrees of abnormalities in the form of endothelial cell enlargement, folding, thickening and protrusion of their luminal surfaces into vascular lumen making it narrower in caliber. In placentae of group III, most of these abnormalities decreased. In most of placentae of group III, the VSM appeared nearly normal in thickness and showed nearly normal composition of one layer of syncytiotrophoblastic cells, one layer of smooth, regular capillary endothelium and the space between them. Mild microvillous abnormalities were noted in few placentae as they appeared short and blunted with mild decrease in their number per micron. The electron picture of syncytial knots appeared nearly normal containing aggregations of small, condensed hyperchromatic nuclei, minimal vacuoles could be seen in the cytoplasm of syncytial knots. Syncytial basement membrane appeared regular and nearly normal in its thickness and composition coming in direct contact with fetal blood capillaries but mild abnormalities were noted in the basement membrane in few placentae as increased its thickness and deposition of fibers or fibrinoid. Regarding cytotrophoblasts in the terminal villi of placentae with controlled diabetes, these cells appeared nearly normal. They were scattered beneath the syncytium and were active containing mitochondria, rough endoplasmic reticulum, free ribosomes and a large nucleus with fine dispersed chromatin. The vascular ultrastructural pattern in terminal villi of placentae of this group showed no significant abnormalities and was normally distributed in the villous tree. The luminal surface of the vascular endothelium appeared regular smooth in the majority of placentae of this group. The endothelial cells appeared connected to each other with tight junctions. It could be concluded that whether if long-term diabetes is controlled or not, placentae of diabetic mother showed a variety of significant histological structural changes seen more frequently than in the placentae of pregnant women without diabetes.


Subject(s)
Diabetes Mellitus , Placenta/ultrastructure , Adult , Egypt , Female , Humans , Microscopy, Electron, Transmission , Pregnancy , Reference Standards
10.
Acta Histochem ; 120(5): 412-419, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29751963

ABSTRACT

The present study aimed to investigate the effects of Bone marrow derived pancreatic progenitor cells (BM- PPCs) in diabetic rats. It was conducted on 30 adult male Sprague-Dawley rats weighing 200-220 g. They were divided into three groups: (a) Group 1 was the control group; (b) Group 2 was the diabetic (induced diabetic by a single intraperitoneal (IP) injection of streptozotocin (STZ) (60 mg/kg) and (c) Group 3 was the treated (received injection of 2.5 X 106 BM- PPCs via the tail vein twice with a 21-day time interval). The blood glucose level was estimated weekly, the oxidative stress and insulin gene expression were evaluated at the end of the experiment. Pancreatic tissue histopathology was performed. The insulin immuno-histochemical reaction was applied to the islets. The blood glucose level was reduced in the treated group over time till reaching its acceptable level whereas it was increased in the diabetic group. The oxidative stress was decreased in the treated group compared to the diabetic one. The treated group showed increased expression of the insulin gene compared to the diabetic group. The immune-histochemical analysis of insulin showed an increased number and size of pancreatic islets in the treated group compared to the diabetic one. Thus, the twofold injection of BM- PPCs could restore the normal beta-cell morphology and function.


Subject(s)
Diabetes Mellitus , Hyperglycemia/therapy , Islets of Langerhans/cytology , Mesenchymal Stem Cell Transplantation , Stem Cells , Animals , Diabetes Mellitus/chemically induced , Flow Cytometry , Insulin/genetics , Insulin/metabolism , Male , Oxidative Stress , Rats , Rats, Sprague-Dawley , Reference Standards
11.
Environ Sci Pollut Res Int ; 24(11): 9886-9894, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27838909

ABSTRACT

Ethanol production from by-products of dates in very high gravity was conducted in batch fermentation using two yeasts, Saccharomyces cerevisiae and Zygosaccharomyces rouxii, as well as a native strain: an osmophilic strain of bacteria which was isolated for the first time from the juice of dates (Phoenix dactylifera L.). The phylogenetic analysis based on the 16S ribosomal RNA and gyrB sequence and physiological analysis indicated that the strain identified belongs to the genus of Bacillus, B. amyloliquefaciens. The ethanol yields produced from the syrup of dates (175 g L-1 and 360 g L-1 of total sugar) were 40.6% and 29.5%, respectively. By comparing the ethanol production by the isolated bacteria to that obtained using Z. rouxii and S. cerevisiae, it can be concluded that B. amyloliquefaciens was suitable for ethanol production from the syrup of dates and can consume the three types of sugar (glucose, fructose, and sucrose). Using Z. rouxii, fructose was preferentially consumed, while glucose was consumed only after fructose depletion. From this, B. amyloliquefaciens was promising for the bioethanol industry. In addition, this latter showed a good tolerance for high sugar concentration (36%), allowing ethanol production in batch fermentation at pH 5.0 and 28 °C in date syrup medium. Promising ethanol yield produced to sugar consumed were observed for the two osmotolerant microorganisms, Z. rouxii and B. amyloliquefaciens, nearly 32-33%, which were further improved when they were cocultivated, leading to an ethanol to glucose yield of 42-43%.


Subject(s)
Ethanol , Hypergravity , Fermentation , Phoeniceae , Phylogeny , Saccharomyces cerevisiae
12.
Biodegradation ; 21(6): 903-13, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20401686

ABSTRACT

Five malathion-degrading bacterial strains were enriched and isolated from soil samples collected from different agricultural sites in Cairo, Egypt. Malathion was used as a sole source of carbon (50 mg/l) to enumerate malathion degraders, which were designated as IS1, IS2, IS3, IS4, and IS5. They were identified, based on their morphological and biochemical characteristics, as Pseudomonas sp., Pseudomonas putida, Micrococcus lylae, Pseudomonas aureofaciens, and Acetobacter liquefaciens, respectively. IS1 and IS2, which showed the highest degrading activity, were selected for further identification by partial sequence analysis of their 16S rRNA genes. The 16S rRNA gene of IS1 shared 99% similarity with that of Alphaprotoebacterium BAL284, while IS2 scored 100% similarity with that of Pseudomonas putida 32zhy. Malathion residues almost completely disappeared within 6 days of incubation in IS2 liquid cultures. LC/ESI-MS analysis confirmed the degradation of malathion to malathion monocarboxylic and dicarboxylic acids, which formed as a result of carboxylesterase activity. A carboxylesterase gene (CE) was amplified from the IS2 genome by using specifically designed PCR primers. The sequence analysis showed a significant similarity to a known CE gene in different Pseudomonas sp. We report here the isolation of a new malathion-degrading bacteria from soils in Egypt that may be very well adapted to the climatic and environmental conditions of the country. We also report the partial cloning of a new CE gene. Due to their high biodegradation activity, the bacteria isolated from this work merit further study as potential biological agents for the remediation of soil, water, or crops contaminated with the pesticide malathion.


Subject(s)
Bacteria/genetics , Bacteria/isolation & purification , Carboxylesterase/genetics , Genes, Bacterial/genetics , Malathion/metabolism , Sequence Analysis, DNA , Soil Microbiology , Amino Acid Sequence , Bacteria/enzymology , Biodegradation, Environmental , Carboxylesterase/chemistry , Chromatography, Gas , Cloning, Molecular , Electrophoresis, Agar Gel , Malathion/chemistry , Mass Spectrometry , Molecular Sequence Data , Pesticides/metabolism , Polymerase Chain Reaction , Pseudomonas putida/growth & development , Pseudomonas putida/metabolism , RNA, Ribosomal/genetics , Sequence Alignment
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