Studies on the interactions between siderophore-producting bacteria and mica minerals will help us understand the mechanism of bio-weathering, the formation of soil, global cycle of several elements, and local environmental contamination. A siderophore(pyoverdins)-producting bacterial strain Z6 was isolated from rhizosphere soil of advantage wild plants sheep sorrel (Rumex acetosa L.) growing in Longshan potassium mine tailings in Nanjing, which was identified as Pseudomonas sp. By checking the individual morphology, colony characteristics, and 16S rDNA sequencing. Using the test cultures containing biotite or muscovite inoculated with Pseudomonas sp. Z6, we found that a strong increase in the amount of siderophore in the fiest 15 days and bacteria could influence silicon and iron mobilization from mica minerals consistently until 75 d of culture. The amounts of iron released from biotite in the presence of Z6 increased by 211 times and the silicon increased by a factor of 27.8, much higher than that in the negative control without minerals. SEM analysis revealed the formation of erosion and bacteria-mineral aggregates on the surface of mica. Cellular growth, siderophere production and pH change by Pseudomonas sp. Z6 cultivated in biotite were directly and quickly influenced, more significantly than that in muscovite experimental setup. The siderophore(pyoverdins)-producting bacterial strain Z6 might play an important role in the process of mica weathering. Production of bacterial siderophore may be related to the presence of different mica minerals.%产铁载体细菌与云母类矿物相互作用的研究有助于了解矿物生物风化和土壤形成的演化规律和机理.采用纯培养法自南京龙山废钾矿区酸模根际土壤分离筛选到一株高产荧光铁载体的细菌Z6,通过16S rDNA序列分析和生理生化反应将其鉴定为假单胞菌属(Pseudomonas sp.)；通过室温静置培养试验研究Z6菌株与云母的相互作用结果表明,细菌生长代谢前期(8～15 d)快速产生大量铁载体,菌株与矿物共培养75 d后,产铁载体细菌对云母类矿物确实产生了风化作用,黑云母组发酵液中Fe含量增加了211倍,Si含量增加了约27.8倍,SEM显示云母表面出现溶蚀坑,细菌可以在矿物表面形成生物膜或矿物-细菌复合物.不同矿物对共培养体系中细菌数量、荧光铁载体含量、溶液pH的影响不同.
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