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Production of 7-methylxanthine from Theobromine by Metabolically Engineered E. coli
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In this work, a novel biocatalytic process for the production of 7-methylxanthines from theobromine, an economic feedstock has been developed. Bench scale production of 7-methlxanthine has been demonstrated. The biocatalytic process used in this work operates at 30 OC and atmospheric pressure, and is environmentally friendly. The biocatalyst was E. coli BL21(DE3) engineered with ndmB/D genes combinations. These modifications enabled specific N7- demethylation of theobromine to 7-methylxanthine. This production process consists of uniform fermentation conditions with a specific metabolically engineered strain, uniform induction of specific enzymes for 7-methylxanthine production, uniform recovery and preparation of biocatalyst for reaction and uniform recovery of pure 7-methylxanthine.

   Many E. coli BL21(DE3) strains metabolically engineered with single and/or multiple ndmB/D genes were tested for catalytic activity, and the best strains which had the higher activity were chosen to carry out the N-demethylation reaction of theobromine. Strain pBD2dDB had the highest activity for the production of 7-methylxanthine from theobromine. That strain was used to find the optimum amount of cells required to achieve complete conversion of theobromine to 7-methylxanthine within two hours. It was found that the optimum concentration of pBD2dDB strain to achieve 100% conversion of 0.5 mM theobromine to 7-methylxanthine was 5 mg/mL. The cell growth of pBD2dDB strain was studied using two different growth media, (Luria-Bertani Broth and Super Broth). Super broth was found to be the best medium to produce the highest amount of cell paste (1.5 g). Subsequently, the process was scaled up in which 2 L reaction volume was used to produce 7-methylxanthine (100% conversion) from 0.5 mM theobromine catalyzed by pBD2dDB strain. The reactions was carried out at 30 oC and 250 rpm shaker speed, and the reaction medium was 50 mM potassium phosphate buffer (pH=7). 7-methylxanthines was separated by preparative chromatography with high recovery, and the product solution was collected, purified by drying at 120-140 oC for 4 hours and, recovered (127 mg). Purity of the isolated 7-methylxanthine was comparable to authentic standards with no contaminant peaks, as observed by HPLC, LC-MS, and NMR. 

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Publication Date
Tue Mar 05 2024
Journal Name
Journal Of Biotechnology Research Center,
A review of the Prevalence of Enterohemorrhagic E. coli in Iraq
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Publication Date
Mon May 22 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Role of Omeprazole in Enhancement of Antibiotic Resistance in E. coli
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E. coli was isolated, and it was Gram-negative rod bacteria that was colony circular, regular edged, thick somewhat glitter and  viscous(less). It was lactose fermenter bacteria and belongs the family of Enterobacteriaceae. E. coli showed sensitivity to all used antibiotics except Erythromycin (E), Cloxacellin (CX), Rifampin (RA), Cephalothin (KF), Ampicillin (AM), and Penicillin (P). The experimental results of antibiotic sensitivity of E. coli in media containing different concentrations of omeprazole, a proton pump inhibitor, showed an enhancement of resistance by decreasing the sensitivity of E. coli inversely with drug concentration against the antibiotics that E. coli was sensitive to. It seems that omeprazole changed cell mem

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Publication Date
Sat Mar 29 2025
Journal Name
Mustansiriyah University
Inhibition the Expression of fimC, fimD, fimH Genes in Uropathogenic E. coli Using TiO2 Nanoparticles Biosynthesized by Probiotics Bacteria
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المستودع الرقمي العراقي. مركز المعلومات الرقمية التابع لمكتبة العتبة العباسية المقدسة

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Publication Date
Sat Jan 01 2022
Journal Name
Revista Electronica De Veterinaria
The Molecular Identification of Pathogenic E. coli Isolated from Raw Cow Milk and Assessment Their Anti-susceptibility to Medical Plants at Al-Najaf city/ Iraq
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Background: Toxin-producing Shiga Escherichia coli has been identified as a new foodborne pathogen that poses a significant health risk to humans. Shiga toxin-producing Escherichia coli can be found in raw cow milk and its derivatives. A small number of Escherichia coli strains that produce shiga toxin are pathogenic. Aim of study: The study aimed to see if there were any virulence genes in 50 milk samples that were typical of Entero-haemorrhagic E. coli and evaluate the Myrtus communis effects on these bacteria. Materials and Method: Milk samples were used to isolate E. coli bacteria (n= 27), biochemically analyzed, and genetically screened for virulence genes using a multiplex (PCR). The hydro-alcoholic extraction of Myrtus communis leave

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Scopus
Publication Date
Wed Mar 29 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Efficacy of Combination of Meropenem with Gentamicin, and Amikacin against Resistant E. coli Isolated from Patients with UTIs: in vitro Study
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         Seventy five E. coli isolates were collected from urine of patients with urinary tract infections in AL-Kadhimia and AL-Yarmook teaching hospitals in Baghdad for a period between 22/11/2009 to 15/3/2010,  from these samples twenty five isolates were selected according to their pattern of the highest resistance as these showing multi-drug resistances and tested to specify their minimum inhibitory concentration for (meropenem, gentamicin and amikacin), meropenem was found having the lowest MIC comparing with others. This study also includes in vitro effects of various combinations of three types of antimicrobials (meropenem, gentamicin and amikacin) against twenty five E. c

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Publication Date
Tue Mar 05 2024
Journal Name
5th International Conference On Biomedical And Health Sciences
Antimicrobial Activity Zinc Oxide ZnO Nanoparticles Against Biofilm Formation of Uropathogenic E. coli
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Publication Date
Sat Jul 03 2021
Journal Name
Indian Journal Of Forensic Medicine & Toxicology,
The Effect of Aqueous Extract of Quercus infectoria Plant on Pap E gene Expression of Uropathogenic Escherichia coli
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One 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

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Publication Date
Thu Jan 01 2015
Journal Name
Iraqi Journal Of Biotechnology
Detection of E. coli and rotavirus in diarrhea among children under five years old‏
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Publication Date
Sun Mar 03 2013
Journal Name
Baghdad Science Journal
Modifying Plaque assay and Clearance test as tools in determination of phage typing for E. Coli bacterial interspecies
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Bacteriophage of E. Coli interspecies from sewage samples were isolated , the phage particles were isolated from two different sewage samples . The first sample was collected from sewage sample of Baghdad university and the second sample was isolated from domestic sewage sample , first sample showed phages specialized for three E. Coli interspecies bacteria (first plate ) and two E. Coli interspecies bacteria (second plate ) , meanwhile second sample showed phage specialized for two E. Coli. interspeciesThe study of appearance of E coli phages from first sample showed three types of E. coli phages with different size of inhibition zone ( 1 , 0.7,0.5 )Cm respectively ( first plate ) , meanwhile E. Coli interspecies bacteria showed phages

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Publication Date
Sun Sep 06 2015
Journal Name
World Journal Of Experimental Biosciences
Effectiveness of some β- lactamase encoding geneson biofilm formation and slime layer production byuropathogenic Escherichia coli
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In present study 74 specimens of urine were collected from patients suffering from urinary tract infections.Fifty (67.56%) isolates were identified as Escherichia coli. 78% of isolates were identified as extendedspectrum beta lactamases (ESBL) producer. Antibiotic susceptibility t est was done and ceftazidime wasselected to complete this study by implying stress at sub-MIC on isolate harbor high number of resistancegenes (N11) and compared with sensitive isolate (S). Only four β-lactamase coding genes were detected;blaTEM, blaPER, blaVIM and blaCTX-M-2 and N11 had blaTEM, blaPER, and blaVIM. It was found that the resistantisolate did not form biofilm when compared with the sensitive one, which formed moderate biofilm. Inaddition, ceftazidi

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