Background:AmpC type β-lactamases are commonly isolated from extended-spectrum Cephalosporin-resistant Gram-negative bacteria. Also, resistance appeared in bacterial species not naturally producing AmpC enzymes. Therefore, a standard test for the detection of the plasmid-mediated AmpC enzyme and new breakpoints for extended spectrum Cephalosporins are urgently necessary.Objectives:To detect plasmid and chromosomal mediated AmpC-β-lactamases in Gram negative bacteria in community and hospital acquired infections.Materials and Methods:1073 Gram negative clinical isolates were identified by the conventional methods and were screened for AmpC production using Cefoxitin discs. Confirmatory phenotypic identifications were done for the Cefoxitin-resistant isolates using Boronic Acid for combined and double disc synergy tests, Cloxacillin based double disc synergy test, and induction tests. The genotypic identification of plasmid-mediated AmpC was done using multiplex PCR. ESBL production was also screened by discs of Ceftazidime and Cefotaxime with and without Clavulanic Acid (10 μg).Results:The AmpC-producing isolates among all identified Gram negative bacilli were 5.8% (62/1073) as detected by screening disc diffusion methods, where 72% were positive for AmpC by combined disc method (Cefotetan and Boronic Acid), 56.5% were positive by each of Boronic Acid and Cloxacillin double disc synergy tests, 35.5% were positive by the induction test, and 25.8% were plasmid-mediated AmpC β-lactamase producers by the multiplex PCR. Plasmid-mediated AmpC genes retrieved, belonged to the families (MOX, FOX, EBC and CIT). ESBL producers were found in 26 (41.9%) isolates, 15 (57%) of which also produced AmpC. Isolates caused hospital acquired infections were (53/62); of which (39/62) were AmpC producers. While only (8/62) of the isolates caused community-acquired infections, were AmpC producers, and (1.6%) (1/62) were non AmpC producer.Conclusions:The AmpC β-lactamases detection tests had to be included in the routine microbiology workup of Gram negative bacteria, namely Cefoxitin as a screening test, combined Boronic Acid disc test with Cefotetan, followed by synergy tests and finally by the induction test for phenotypic identifications. Multiplex PCR can successfully detect the plasmid AmpC genes.

In this study we isolate and identify the Enteropathogenic Escherichia coli (EPEC) causing diarrhea in children less than five years in Cairo, Egypt, during different seasons. Children younger than five years with diarrhea, attending the Pediatric Gastroenterology Intensive Care Unit of the Cairo University Pediatric Hospital in one year period were our group of study. Our control group was age and sex matched concurrent healthy children. The identified E. coli isolates were subjected to antimicrobial disc diffusion susceptibility test and further identified for EPEC serotype by slide agglutination test, using antiserum E. coli somatic trivalent I (O111, O55, O26) according to the instructions of the manufacturer. Out of 134 patients 5.2% of them revealed EPEC in the fecal sample, while the 20 children control group showed no EPEC isolates in their samples. Our EPEC frequency showed variations from the compared results of other studies. Higher rate of EPEC (18.7%) was found in patients between 2 to 3 years, while EPEC rate was (7.5%) in patients less than 6 months old, with P < 0.05. EPEC was identified from fecal specimens as a unique pathogen or associated with other pathogens in acute and chronic diarrhea in children. EPEC were detected in all seasons except in winter, and was predominant in summer season. Four (57%) EPEC isolates were resistant to ampicillin, ticarcillin, and cotrimoxazole, and (14.3%) to the third generation cephalosporins.

BK and JC polyomaviruses (PyV) have been demonstrated to be associated with the pathogenesis of various human cancers. We aimed to investigate the impact of BK and JC polyomavirus infections on several clinical parameters in different human cancers. A total of 150 cancer patients were included in the study (51 patients with solid tumors, 48 patients with lymphomas and 51 patients with leukemias). Amplification of PyV DNA was performed using a semi-nested version of Polymerase chain reaction targeting the T genomic region of PyV. The polyomavirus load was determined using real-time PCR assay. The clinical data were collected. Polyomavirus DNA could be detected in 84 (56%) of 150 of all cancerous patients. The solid tumors had the lowest proportion of JCV (6 (11.8%) of 51), whereas had the highest proportion of JCV (200copies/μl). JCV was more frequent among NHL patients (30%) and absent in HL patients (0%). During follow-up, PyV positivity decreased significantly (p=0.004) in lymphoma patients (n=28). Although PyV positivity decreased significantly from 39% to 7% in 28 of 48 lymphoma patients after treatment, it significantly persisted in leukemic patients after treatment (from 22% to 38%). JC was more frequent among leukemic patients with leukopenia. The presence of JC polyomavirus was more frequent among leukemic patients without any significant impact on their overall survival.

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The gene encoding sucrose phosphorylase (742sp) in Leuconostoc mesenteroides NRRL B-742 was cloned and expressed in Escherichia coli. The nucleotide sequence of the transformed 742sp comprised an ORF of 1,458 bp giving a protein with calculated molecular mass of 55.3 kDa. 742SPase contains a C-terminal amino acid sequence that is significantly different from those of other Leu. mesenteroides SPases. The purified 742SPase had a specific activity of 1.8 U/mg with a K (m) of 3 mM with sucrose as a substrate; optimum activity was at 37 degrees C and pH 6.7. The purified 742SPase transferred the glucosyl moiety of sucrose to cytosine monophosphate (CMP).

Increased consumption of fossil fuels is an emerging problem. Scientists look for the existence of other alternatives to fossil fuels, including so-called renewable energy. Accordingly, we report the production of bio-ethanol from the remnants of castor oil bean seed cake (CBC) by the carboxymethylcellulase enzyme (CMCase). A bacterial strain isolated from rice straw showing higher CMCase activity was identified. The 16S rRNA result showed a 93% homology with the 16SrRNA gene sequences of Pseudomonas poae RE∗1-1-14, the strain was identified as Pseudomonas poae AB3. In addition, our results showed that the highest enzyme activity was achieved after 48 h and inoculum size of 3.7 × 10 5 CFU. The optimum temperature, pH and Carboxymethylcellulose (CMC) concentration for the highest enzyme activity was 25 °C, pH 7 and 10 g/l respectively. Furthermore, The CMCase was purified by ammonium sulphate at a concentration of 60%. The SDS-PAGE of the purified enzyme showed a molecular weight of 88 kDa. Additionally, the (CBC) was hydrolyzed by the purified CMCase at the enzyme optimum conditions. The results showed the liberation of 5.2 g/L of reducing sugar by using dinitrosalicylic acid (DNS) assay. Finally, the total sugar produces 35 g/L after 48 h when Saccharomyces cerevisiae was used as a fermentation agent . Hence for the first time, we have been successfully able to produce bioethanol from CBC with CMCase of Pseudomonas poae .

Amidases are ubiquitous enzymes that have received increased attention due to their wide range of biotechnological applications, especially in industries for the synthesis of wide variety of carboxylic and hydroxamic acids, which find applications in pharmaceuticals, agrochemicals and waste water treatments. In the present study, 40 bacterial isolates were screened for extracellular amidase-producing capability, and on the basis of color development, 5 isolates were selected for amidase production in broth media. Based on enzyme production, one of the most potent isolates identified as Pseudomonas putida AP-2 was selected for further study. The effects of media composition and various fermentation conditions for optimization of amidase production were studied. The maximum extracellular amidase production was obtained at 30°C and pH 8.0 after 36 h of incubation in shaking condition. Among the substrate, acetamide was the best; however, P. putida AP-2 also utilized acrylamide which is a known carcinogen. Regarding carbon sources, glucose was the best, while peptone was found the best nitrogen source. The isolated bacterium, P. putida AP-2, is also tolerant to number of heavy metals at higher levels so this may also be applied for field application in contaminated soil.

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