Occurrence of Salmonella genomic island 1 (SGI1) in two African Proteus mirabilis strains isolated from diseased chicken flocks.
Two P. mirabilis strains, PmSHR21 and PmSHR38, were collected from chicken flocks in Sharkia Governorate, Egypt in 2016. The two strains showed multidrug-resistance (MDR) phenotypes and were detected to harbour I) floR and sul1 genes conferring resistance to florfenicol and chloramphenicol, and sulfonamides, respectively, II) a ~1.9 kbp class 1 integron containing aadA2-lnuF genes conferring resistance to spectinomycin and streptomycin, and lincosamides, respectively. Interestingly, the two strains were detected to contain SGI1 variant, SGI1-W and inserted between the 3' end of the chromosomal trmE gene and the hipB/hipA toxin/antitoxin homologue. Fingerprinting by ERIC-PCR of the two poultry strains identified in this study and the two human SGI1-carrying P. mirabilis strains described recently in our study showed identical ERIC-pattern between SGI1-W-carrying poultry and human strains, suggesting that they might be clonally related. The detection of SGI1 and its variants in P. mirabilis isolated from humans and chicken flocks in Egypt clarify the geographical and biological spreading through an inter-transmission pathway. To the best of our knowledge, this is the first study detecting SGI1-positive P. mirabilis isolated from chicken flocks in Africa.
Emergence of Salmonella Genomic Island 1 Variant SGI1-C in a Multidrug-Resistant Clinical Isolate of Klebsiella pneumoniae ST485 from Egypt
Salmonella genomic island 1 (SGI1) is a 42.2-kb integrative mobilizable element (IME), that was originally identified in Salmonella enterica serovar Typhimurium DT104 (1).….
Temperature effects on lily development rate and morphology from the visible bud stage until anthesis.
Day (DT) and night temperatures (NT) influenced Lilium longiflorum Thunb. 'Nellie White' stem elongation and development rate from the visible bud stage (VB) until anthesis. Plant height increase after VB was a function of the difference (DIF) between DT and NT (DT-NT). Plant height increased 90% as DIF increased from - 16 to 16C. A cubic model described bud development rate as a function of temperature from 14 to 30C. A linear model adequately described bud development rate as a function of average daily temperature from 14 to 21C. Based on the linear model, bud development rate increased 0.05 per day for each 1C increase in average daily temperature. The base temperature for bud development, i.e., the temperature at which bud development rate was 0, was calculated as 3.5C. Greenhouse forcing of vernalized Easter lilies is commonly divided into three phases: I) placement of vernalized bulbs in the greenhouse to flower initiation, II) flower initiation to VB, and III) VB to anthesis (De Hertogh and Wilkins, 1971). Plant morphological development differs during each of the forcing phases (De Hertogh and Wilkins, 1971). Growth during phase I is vegetative and consists of stem elongation and leaf expan- sion. Flower initiation, leaf expansion, and stem elongation oc- cur during phase II. Inflorescence expansion and stem elongation occur during phase III. Lily responses to temperature during phase III differed from those during phases I and II (Wang and Roberts, 1983). Lily development rate, quantified as days to unfold a leaf, is a de- creasing linear function of average daily temperature between 14 and 30C during phases I and II (Karlsson et al., 1988). Lily development rate during phase III is a nonlinear function of temperature (Healy and Wilkins, 1984). The effect of temper- ature on the rate of lily development decreases as DT and/or NT increase during phase III (Rob and Wilkins, 1973; Healy and Wilkins, 1984). Easter lily morphological development is thermomorpho- genie. For instance, internode length increases as the DIF be- tween DT and NT increases (Erwin et al., 1989). In addition, leaf orientation, leaf length, and flower length are also influ- enced by diurnal changes in temperature.