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Background and study aims Diarrhoea and urinary tract infection (UTI) are common clinical problems. Meanwhile, Escherichia coli (E. coli), is the commonest bacterial pathogen reported in both of them. This study aimed to evaluate the pathogenic E. coli (PEC) in stool of acute diarrhoea and urine of UTI regarding their virulence genes and their influence on the susceptibility to routinely prescribed antibiotics. Patients and methods Twenty two stool and another 22 urine samples of patients with acute diarrhoea and UTI respectively were collected from patients admitted at Kasr Al-Ainy Hospital, Faculty of Medicine, Cairo University, Egypt. E. coli isolation, identification of their phyla; chuA, yjaA, and TspE4.C2, and further identification of 10 virulent genes; fimH, papC, papG//, papG///, papEF, afa, sfa, CNF1, iroN & hlyA was performed. Antibiotic susceptibility was studied against quinolones , gentamicin (GM), and trimethoprim-sulphamethoxazole (TMP-SMX). Results The studied virulence genes were comparably detected in both pathogenic samples. In diarrheogenic E. coli (DEC); phylum A was significantly related to both ciprofloxacin (CIP) and TMP-SMX resistance, and both of the virulence genes fimH and iroN were significantly related to all the studied antibiotics resistance, while afa was significantly related to nalidixic acid (NA) resistance. In uropathogenic E. coli (UEC); phylum D was significantly related to CIP and levofloxacin resistance, and both of the virulence genes fimH and iroN were significantly related to most of the studied antibiotics resistance. Conclusion The isolated PEC was evidently and broadly resistant to the studied antibiotics, with limited influence of their phyla and virulence genes (fimH and iroN).

In this study, we report a novel approach for preparing precipitated calcium carbonate for the first time by Bacillus licheniformis using different types of media containing urea as a source of urease enzyme and for the first time using particles of pure calcium. The bacteria used in this study produced urease which catalyzes the hydrolysis of urea (CO(NH 2 ) 2 ) into ammonium (NH 4 ) and carbonate (CO 3 2− ) leading to the precipitation of calcium carbonate. Calcium carbonate precipitation was experimentally studied by spontaneous precipitation at various pH (8–12), temperatures (30, 35, 40, 45, 50 °C), and at different concentrations of urease enzyme (1, 5, 10 mg mL −1 ). The XRD results showed a mixture of calcite and vaterite. The morphology of calcium carbonate particles prepared was studied under SEM after using it as a bioconsolidation of degraded fresco wall paintings.

Efficiencies of local bacterial isolates in malathion degradation were investigated. Five bacterial isolates obtained from agricultural waste water were selected due to their ability to grow in minimal salt media, supplied with 250 ppm malathion as sole source of carbon and phosphorus. The purified bacterial isolates (MOS-1, MOS-2, MOS-3, MOS-4 and MOS-5) were characterised and identified using a combination of cellular profile (SDS-PAGE), genetic make up profile (RAPD-PCR), and morphological and biochemical characteristics. Four bacterial isolates (MOS-1, MOS-2, MOS-3 and MOS-4) with identical genetic characteristics were identified as Enterobacter aerogenes , whereas isolate MOS-5 was identified as Bacillus thuringiensis . The degradation rate of malathion in liquid culture was estimated during 15 days of incubation for the isolate MOS-5 of B. thuringiensis . Slightly more than 50% of the initial malathion was decomposed within 3 days. The malathion concentration decreased to almost 17% in the inoculated medium after 10 days incubation, while more than 91% of the initial malathion was degraded after 15 days.