Leul Melakeselam, Mohapatra Anasuya, Sellstedt Anita
Department of Plant Physiology, Umeå Plant Science Centre, Umeå University, S-901 87 , Umeå, Sweden.
Curr Microbiol. 2005 Jan;50(1):17-23. doi: 10.1007/s00284-004-4323-6. Epub 2004 Dec 8.
Eighteen Frankia strains originally isolated from nine different host plants were used to study the biodiversity of hydrogenase in Frankia. In the physiological analysis, the activities of uptake hydrogenase and bidirectional hydrogenase were performed by monitoring the oxidation of hydrogen after supplying the cells with 1% hydrogen and the evolution of hydrogen using methyl viologen as an electron donor, respectively. These analyses were supported with a study of the immunological relationship between Frankia hydrogenase and other different known hydrogenases from other microorganisms. Uptake hydrogenase activity was recorded from all the Frankia strains investigated. A methyl-viologen-mediated hydrogen evolution was recorded from only four Frankia strains irrespective of the source of Frankia. From the immunological and physiological studies, we here report that there are at least three types of hydrogenases in Frankia: Ni-Fe uptake hydrogenase, hydrogen-evolving hydrogenase, and [Fe]-hydrogenase. An immunogold localization study, by cryosection technique, of the effect of nickel on the intercellular distribution of hydrogenase proteins in Frankia indicated that nickel affects the transfer of hydrogenase proteins into the membrane.
从9种不同宿主植物中最初分离出的18株弗兰克氏菌菌株被用于研究弗兰克氏菌中氢化酶的生物多样性。在生理分析中，分别通过在向细胞供应1%氢气后监测氢气的氧化以及使用甲基紫精作为电子供体监测氢气的释放，来测定吸收氢化酶和双向氢化酶的活性。这些分析得到了一项关于弗兰克氏菌氢化酶与其他微生物中其他不同已知氢化酶之间免疫关系研究的支持。在所研究的所有弗兰克氏菌菌株中都记录到了吸收氢化酶活性。无论弗兰克氏菌的来源如何，仅在4株弗兰克氏菌菌株中记录到了甲基紫精介导的氢气释放。从免疫和生理研究中，我们在此报告，弗兰克氏菌中至少存在三种类型的氢化酶：镍铁吸收氢化酶、放氢氢化酶和[铁]氢化酶。通过冷冻切片技术对镍对弗兰克氏菌中氢化酶蛋白细胞间分布的影响进行的免疫金定位研究表明，镍会影响氢化酶蛋白向膜的转移。
