This research was aimed to the purification and characterization of cytosine deaminase as a medically important enzyme from locally isolated Escherichia coli; then studying its cytotoxic anticancer effects against colon cancer cell line. Cytosine deaminase was subjected to three purification steps including precipitation with 90% ammonium sulfate saturation, ion exchange chromatography on DEAE-cellulose column, and gel filtration chromatography throughout Sephadex G-200 column. Specific activity of the purified enzyme was increased up to 9 U/mg with 12.85 folds of purification and 30.85% enzyme recovery. Characterization study of purified enzyme revealed that the molecular weight of cytosine deaminase produced by E. coli was about 48 KDa, the highest enzyme activity at pH 8.5, and is most stable at pH 7.5 - 9, the enzyme also showed a full activity at a range of temperatures between 45-60 0C. Enzyme activity was strongly inhibited in the presence of mercuric chloride and copper sulphate, when added individually at a constant concentration. However, calcium chloride, manganese chloride and ferric chloride caused a little increase in enzyme activity while sodium azide had no effect on enzyme activity. Upon cytotoxic effect study through micro-cultured tetrazolium assay (MTT) against Caco-2 cell line. Purified cytosine deaminase was found to inhibit the growth of Caco-2 cancer cell line with an IC50 of 242.5 ?g/ml in a comparison to an IC50 of 1864 ?g/ml for crude enzyme. Besides, the enzyme didn’t show significant effect on WRL normal cell line.
Thiazoles are heterocyclic nitrogenous compounds, which were given a great attention due to their antibacterial effect, antihypertensive, stimulating glucose absorption (like antibiotics), acts as cytoprotective agent. The present work is conducted to evaluate the degree of antibacterial activity on the growth activity of Escherichia Coli (E.Coli) and Pseudomonas aeruginosa (P. aeruginosa) by incubation with 2-methyl-4-(3,4 dihydroxy phenyl)-Thiazole compound (MDHPT). Optical density (O.B) was measured by turbidmetric method, any increase in O.D would represent the increase in the bacterial growth .The results showed that there was a 75.7 % inhibition when using 190.4 ïg/ml (MDHPT) solution and 64.3% was obtained when using concentr
... Show MoreBackground: Common and persistent isolate ina the teeth following failed therapy of the root canal is the gram-positive facultative bacterium Enterococcus faecalis and Escherichia coli, which develop biofilm through a complicated process that results in the formation of a biofilm. Enterococcus faecalis and Escherichia coli are significant factors that cause chronic periradicular lesions after root canal therapy. Aim: This study aimed to treat the root canal tooth infected with Escherichia coli and Enterococcus faecalis Methods: In this study biofilm formation was done for Escherichia coli in growth phase cultured in a brain heart broth Enterococcus faecalis and Escherichia coli cultured in Luria-Bertani (LB) infusion medium for 18 hrs. Then
... Show MoreOne hundred twelve urine samples were collected from Baghdad hospitals and examined by different identification techniques. Seventy isolates (62.5%) were diagnosed as Escherichia coli after microscopic and cultural identifications. The result of PCR product electrophoresis on the isolates showed that thirteen isolates (18.57%) have Pap E gene which are uropathogenic E. coli. Antibiotic susceptibility test was done, and four high resistant strains were mixed with aqueous extract of Quercus infectoria plant in 96 well ELISA plate and incubated for different times. After 0, 6, and 12 hr. of incubation, the effect of the plant extract on the bacterial growth was determined by ELISA reader, and the effect on the expression of P
... Show MoreLeinamycin is a thiol dependent DNA alkylating agent which shows very potent activity against various cancer cell lines. This natural compound forms guanine adducts (N7) in DNA which are converted into a basic sites and simultaneously generates Reactive Oxygen Species (ROS), to produce DNA strand breaks in human cancer cells. In present study, eight different strains isolated from Iraqi soils were taxonomically assigned as Streptomyces.atroolivaceous. Remarkably the strain named as THS-44 was distinguished in productivity in comparison with other strains; the amount of leinamycin was 50.98 mg/l. In this study, we assessed the cytotoxic activity of leinamycin against RD and ANM3 cancer cell line in compare with REF cell line as a normal cont
... Show MoreIn humans, Pseudomonas aeruginosa is the second most frequent gram negative nosocomial pathogen in hospitals and has the highest case-fatality rate of all hospital-acquired bacteremia because of the hardy resistance of these bacteria to mechanical cleansing as well as to disinfectant, and many antibiotics. The susceptibility of bacteria against the antibiotics is modulated by several local factors such as temperature which modified drug efficacy, so this study was carried out to evaluate the effect of different temperature (20,42,45)Ċon the susceptibility of Pseudomonas aeruginosa to the minimum inhibitory concentrations (MIC) of the antimicrobial agents before and after irradiation. The samples collected from 150 persons suffering from
... Show MorePhenotypic And genotypic characteristics of Salmonella enterica serotype Typhi have been determined for 29 isolates, from Baghdad in 2007. Conventional typing methods were performed by biochemical tests, and antimicrobial susceptibility test. Molecular typing performed by analysis plasmid DNA beside using the Random Amplified Polymorphic DNA (RAPD-PCR). For the latter, two universal primers that have selected for the high discriminatory power were used for RAPD analysis. All isolates were belong one biotype according to the differention by their ability to decarboxylat lysine, 29(100%) were lysine (+). All the isolates were susceptible to the Antibiotics used. However, all the strains free of plasmids. RAPD was capable of grouping the strai
... Show MoreWe studied the effect of certain environmental conditions for removing heavy metal elements from contaminated aqueous solutions (Cd, Cu, Pb, Fe, Zn, Ni, Cr) using the bacterium Bacillus subtilis to appoint the optimal conditions for removal ,The best optimum temperature range for two isolate was 30-35○C while the hydrogen number for the maximum mineral removal range was 6-7. The best primary mineral removal was 100 mg/L, while the maximum removal for all minerals was obtained after 6 hrs of Cu element time and the maximum removal efficiency was obtained after 24 hrs of Cu element. The results have proved that the best aeration for maximum removal was obtained at rotation speed of 150 rpm/minute. Inoculums of 5ml/100ml which contained 1
... Show MoreThe guava plant, Psidium guajava L., serves as proof of the abundant donations of nature, providing a delicious guava fruit; this plant is rich in groups of medicinal and nutritional benefits. Guava belonging to the Myrtaceae family, many previous studies reported many phytochemical constituents in its leaves that have many pharmacological activities and medicinal properties; this study focuses on the isolation, structural elucidation and calculation concentration of flavonoids, assessment of the cytotoxic activityof hyperin from Psidium guajava leaves newly cultivated in Iraq. The isolation process involved the use of thin-layer chromatography (TLC) and preparative high-performance liquid chromatography (PHPLC) and structural eluci
... Show MoreHuman Adenosine deaminase is an essential enzyme for modulating the bioactivity of thyroid hormones, and It is important for the maturation and differentiation of lymphocytes, although its clinical importance in thyroid diseases have yet to be identified. Objective: The aim of the current study is to determine the Adenosine deaminase concentration in healthy controls, and in autoimmune thyroid diseases such as Graves' Disease, and Hashimoto's Thyroiditis. Patients and methods: A total of 183 serum specimens of 103 female patients with autoimmune thyroid diseases and 80 healthy control groups were included in this study and collected from the Baghdad Medical City, Iraq. Quantitative Human Adenosine Deaminase ELISA kits were used to estimate
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