Microbial treatment for vanadium contamination of soils is a favorable and environment-friendly method. However, information of the resistant mechanism of the strains in soils to vanadium, especially to tetravalent vanadium [vanadium(IV)], is still limited. Herein, potential of the vanadium(IV) biosorption and biotransformation of the strains (4K1, 4K2, 4K3 and 4K4) which were capable of tolerating vanadium(IV) was determined. For biosorption, the bioadsorption and the bioabsorption of vanadium(IV) occur on the bacterial cell wall and within the cell, respectively, were taken into consideration. Comparison of the vanadium(IV) adsorbed on the bacterial cell walls and remained in the cells after sorption indicated the major bacterial vanadium(IV) sorption role of the bioadsorption which was at least one order of magnitude higher than the bioabsorption amount. Isotherm study using various isotherm models revealed a monolayer and a multilayer vanadium(IV) biosorption by 4K2 and the others (4K1, 4K3 and 4K4), respectively. Higher biosorption was observed in acidic conditions than in alkaline conditions, and the maximum biosorption was 2.41, 9.35, 7.76 and 8.44 mg g⁻¹ observed at pH 6 for 4K1, at pH 3 for 4K2, and at pH 4 for 4K3 and 4K4, respectively. At the present experimental range of the initial vanadium(IV) concentration, optimal biosorption capacity of the bacteria was observed at the vanadium(IV) level of 100–250 mg L⁻¹. Different biotransformation level of vanadium(IV) in soils by the stains was observed during a 28-d pot incubation of the soils mixed with the strains, which can be attributed to the discrepancy of both soil properties and bacterial species. Present study can help to fill up the gaps of the insufficient knowledge of the vanadium(IV) resistant mechanism of the strains in soils.

微生物处理土壤中的钒污染是一种有利且环保的方法。但是，土壤中的菌株对钒，特别是对四价钒[钒（IV）]的抗性机理的信息仍然有限。在此，确定了能够耐受钒（IV）的菌株（4K1、4K2、4K3和4K4）对钒（IV）的生物吸附和生物转化的潜力。对于生物吸附，考虑了分别在细菌细胞壁上和细胞内发生的钒（IV）的生物吸附和生物吸收。比较吸附在细菌细胞壁上的钒和吸附后残留在细胞中的钒，表明生物吸附的主要细菌对钒的吸附作用比生物吸附量高至少一个数量级。使用各种等温线模型进行的等温线研究分别显示了4K2和其他（4K1、4K3和4K4）的单层和多层钒（IV）生物吸附。在酸性条件下观察到的生物吸附量比碱性条件下更高，最大生物吸附量为2.41、9.35、7.76和8.44 mg g对于4K1在pH 6处观察到^-1，对于4K2在pH 3处观察到的，对于4K3和4K4在pH 4处观察到的。在当前钒（IV）浓度的当前实验范围内，在100-250 mg L ^-1的钒（IV）水平下观察到细菌的最佳生物吸附能力。在与菌株混合的土壤中进行28天锅温育时，观察到的污渍在土壤中钒（IV）的生物转化水平不同，这可能归因于土壤性质和细菌种类的差异。当前的研究可以帮助填补对土壤中菌株抗钒（IV）机理的认识不足的空白。