Key Laboratory of Biogeology and Environmental Geology, Ministry of Education (BGEG), School of Environmental Studies, China University of Geosciences, 388 Lumo Road, Wuhan, Hubei, 430074, China.
Ecotoxicology. 2010 Apr;19(4):593-603. doi: 10.1007/s10646-009-0420-4. Epub 2010 Jan 12.
Natural Cr-(III)-organic species are being known as the part of natural biogeochemical cycle of chromium, but unfortunately, their mechanism of toxicity as well as genotoxic potentiality is still unknown. To evaluate the characteristic toxic effect exerted by natural Cr-(III)-organic species on the cellular macromolecules, changes in DNA and protein level was observed. Besides, Comet assay was applied to measure genotoxic potentiality of Cr-(III)-organic species in the target organism Saccharomyces cerevisiae exposed to Cr-(III)-citrate and Cr-(III)-histidine. It has been observed that both of the Cr-(III)-organic compounds are responsible for diminution in macromolecules concentration. Cr-(III)-citrate showed ladder pattern of DNA fragmentation in support of apoptosis. Two new protein bands appeared in protein profile of the Saccharomyces cerevisiae treated with Cr-(III)-organic compounds. Thus it supports the possibility of the synthesis of stress proteins. Comet assay proved positive correlation between Cr-(III)-organic compounds' concentration and DNA damage. The Cr-(III)-citrate causes DNA damage at the concentrations ranging from 50 to 150 mg L(-1), whereas the DNA damaging capacity of Cr-(III)-histidine was found insignificant, except at highest concentration (150 mg L(-1)). These results can throw light on the mechanism of the toxic effect as well as genotoxicity exerted by natural Cr-(III)-organic species.
天然 Cr-(III)-有机物种被认为是铬的自然生物地球化学循环的一部分,但不幸的是,它们的毒性机制和遗传毒性潜力仍然未知。为了评估天然 Cr-(III)-有机物种对细胞大分子的特征毒性作用,观察了 DNA 和蛋白质水平的变化。此外,还应用彗星试验来测量目标生物酿酒酵母中 Cr-(III)-柠檬酸和 Cr-(III)-组氨酸暴露下 Cr-(III)-有机物种的遗传毒性潜力。结果表明,这两种 Cr-(III)-有机化合物都导致了大分子浓度的降低。Cr-(III)-柠檬酸在支持细胞凋亡的情况下显示出 DNA 片段化的梯状模式。在用 Cr-(III)-有机化合物处理的酿酒酵母的蛋白质图谱中出现了两条新的蛋白质条带。这支持了应激蛋白合成的可能性。彗星试验证明了 Cr-(III)-有机化合物浓度与 DNA 损伤之间存在正相关关系。Cr-(III)-柠檬酸在 50 至 150mg/L 的浓度范围内会引起 DNA 损伤,而 Cr-(III)-组氨酸的 DNA 损伤能力除了在最高浓度(150mg/L)时外,均不显著。这些结果可以阐明天然 Cr-(III)-有机物种产生的毒性作用和遗传毒性的机制。