Marmar A. El Siddig

Isolation and 16S rRNA-Based Identification of Benomyl -Degrading Bacteria

Laboratory experiments were conducted to isolate and identify Benlate - (Benomyl) degrading microorganisms from two soil types collected from different locations in Khartoum State, Sudan. Benomyl degradationwas studiedat two temperatures (28 and 40∫C) in soil treated with three Benomyl con centrations (0.032, 3.2 and 8.0 mg Benomyl/g soil) and incubated for 360 days. Potential degraders were also tested in mineral salt liquid medium using Benomyl as a sole carbon source. Degradation percentages were then determined and the most efficient Benomyl degraders were identified by amplification with 16S rRNA gene, sequencing and alignment with deposited sequences in the international gene bank. A total of 64 isolates were recovered from the two soil types, with 59 (92.2%) isolates recovered from the clay soil. Thirty four isolates were recovered from clay soil treated with 8.0mg Ben omyl/g soil and incubated at 28∫ C. The most efficient Benomyl degraders, with degradation percentages in the range of 44 -59, were identified as Pseudomonas stutzeri (Two different isolates) , Pseudomonas putida, Acinetobacter johnsonii, Brevibacillus invocatus, Bacillus clausii, Lysinibacillussp. andAgrobacterium radiobacter.

Prevalence, Detection and Antimicrobial Resistance Pattern of Salmonella in Sudan

Infectious microbial diseases constitute a major cause of death in many parts of the world, particularly in developing countries. Salmonella has been identified as an important food and water-borne pathogen that can infect human and animals resulting in significant morbidity and mortality (Akkina et al., 1999). Salmonella is a facultative anaerobe, Gram-negative rodshaped, 2 – 3 x 0.4 – 0.6 μm in size and motile by peritrichous flagella except for S. Gallinarum and S. Pullorum which are immotile. Members of the genus have a % G+C content of 50-53. They are urease and Voges-Proskauer negative and citrate utilizing (Montville and Matthews, 2008).

Complete genome sequence of datura leaf curl virus, a novel begomovirus infecting Datura innoxia in Sudan, related to begomoviruses causing tomato yellow leaf curl disease

Several species in the genus Datura (family Solanaceae) are hosts for begomoviruses (family Geminiviridae), both in the New World and the Old World. Here, we report the genome characterization of two isolates of a novel Old World monopartite begomovirus infecting Datura innoxia in Sudan, which we propose to be named “datura leaf curl virus” (DaLCV). Pairwise sequence comparisons and phylogenetic analysis showed that DaLCV isolates are related to begomoviruses causing tomato yellow leaf curl disease, a global menace for tomato crops. Thus, the novel begomovirus could pose an additional threat to tomato cultivation in Africa.

CURRENT PATTERNS AND PREDICTIVE TRENDS OF MULTIDRUG-RESISTANT SALMONELLA TYPHI IN SUDAN

Background Enteric fever has a persistently great impact on public health. It is caused by Salmonella enterica associated with malaria during the rainy season; the bacterium is seldom detected in wastewater of stabilisation stations due to treatment processes. The aim of this study is to evaluate the recent state of antibiotics susceptibility of Salmonella typhi with special attention to multidrug-resistant strains and predict the emergence of new resistance patterns. Methods S. typhi isolates were recovered from 128 wastewater samples collected from ponds at Soba Stabilization Station and Omdurman Hospital Stabilization Station. The isolates were identified using standard Salmonella identification guidelines and their susceptibility to seven antibiotics was determined. Minimum inhibitory concentration (MIC) of ciprofloxacin and minimum bactericidal concentrations (MBC) were also determined. Statistical predictions for the resistance emergence were done using logistic regression and forecasting linear equations. Results A total of 12 S. typhi isolated strains were recovered from 128 samples of wastewater; they were resistant to antibiotics except Ciprofloxacin. Current patterns of ciprofloxacin breakpoints interpretations were in susceptible ranges by disc diffusion (S≥20 mm), minimum inhibitory concentration was recorded as (I=16 µg/ml) and minimum bactericidal concentration=(R≥32 µg/ml). The probability of an isolate to develop resistance was plotted for MBCs; the rate of resistance solved by (y=0.0235×−0.0411). The predictive patterns of resistance were spontaneously solved using exponential trend (y=n ex) for each isolate at 16 µg/ml and 32 µg/ml of ciprofloxacin in certain period and the high values of coefficient R2>0.5 indicate the incidence rates of bacterial resistance. Conclusions The current sensitivity patterns of S. typhi isolates against ciprofloxacin were acceptable, but the probability of emerging multidrug resistance to ciprofloxacin was observed in sensitivity which had begun to decline according to frequent consuming, drug policy and bacterial genetic mutations.