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681.
An assessment of a method based on intrinsic antibiotic resistance for identifying Rhizobium strains
A method based on intrinsic antibiotic resistance (IAR) for identifying large numbers of Rhizobium strains was assessed and found to be unsatisfactory for R. phaseoli and isolates from Cicer arietinum (Rhizobium spp.). Our data showed that the number of different IAR patterns always exceeded the number of strains tested. With 90 nodule isolates from plants inoculated with a mixture of three strains of R. Phaseoli, the technique gave 18 different resistance patterns. When 24 strains of Rhizobium spp., each replicated three times, were examined 68 different resistance patterns were obtained. Single colony isolates from one strain also gave several different IAR patterns. All strains tested with fluorescent“ antibody were readily identified. Attempts to obtain correct strain identification with IAR by simplifying the scoring systems or allowing up to two differences in the resistance patterns were unsuccessful. We were unable to define the source of this variation although incubation time and inoculum concentration were shown to affect the IAR patterns 相似文献
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Two newSalmonella types isolated from patients in the Netherlands are described:S. zuilen (1, 2, 19: i: 1. w) andS. alexanderpolder (8: c: 1. w). 相似文献
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Partha Sarathi Guin Saurabh Das P.C. Mandal 《Journal of inorganic biochemistry》2009,103(12):1702-1710
Copper(II) forms a complex with sodium 1,4-dihydroxy-9,10-anthraquinone-2-sulphonate (sodium quinizarin-2-sulphonate, NaQSH2), an analogue of the core unit of anthracycline antibiotics used in the treatment of cancer. The 1:2 metal-ligand complex is formed in aqueous solution at neutral and acidic pH while in alkaline pH both 1:1 and 1:2 species are formed. The effective stability constant of the 1:2 metal-ligand complex is 9.64 × 1016 while that of the 1:1 metal-ligand complex is 9.4 × 109. The 1:2 complex Cu(NaQSH)2(H2O)2 was synthesized and characterized by different techniques in solid state and in solution. The complex Cu(NaQSH)2(H2O)2 interacts with calf thymus DNA which was studied by fluorescence spectroscopy. The binding constant and site size for the interaction with DNA were determined. 相似文献
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