Hydrogen evolution under photoheterotrophic and dark fermentative conditions by recombinant Rhodobacter sphaeroides containing the genes for fermentative pyruvate metabolism of Rhodospirillum rubrum
Hydrogen evolution under photoheterotrophic and dark fermentative conditions by recombinant Rhodobacter sphaeroides containing the genes for fermentative pyruvate metabolism of Rhodospirillum rubrum
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DOI：
10.1016/j.ijhydene.2008.05.009
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发表时间：
2008-10-01
影响因子：
7.2
通讯作者：
Lee, Jeong K.
中科院分区：
文献类型：
--
作者：
Kim, Eui-Jin;Kim, Mi-Sun;Lee, Jeong K.
球形红杆菌KCTC 12085是一株光合异养产氢能力较强的天然菌株。sphaeroides 2.4.1. R. sphaeroides仅在光照条件下观察到。为了使R. sphaeroides产生H-2发酵酶的菌株，一个4.4-kb的红色红杜鹃菌DNA，包含一个编码丙酸-甲酸裂解酶（PFL）及其成熟蛋白的基因，和一个29.4-kb的R.将包括甲酸氢裂解酶（FHL）复合物及其成熟蛋白、FHL转录激活因子和唯铁氢酶及其成熟蛋白的rubrum基因簇克隆到红曲霉中，并将其转入到红曲霉中。sphaeroides KCTC 12085.重组R. sphaeroides在黑暗发酵生长期间进化H-2。重组R.在光异养条件下，类球孢菌的产氢能力比携带空载体的亲本菌株的产氢能力提高了两倍，达到4 mol H-2/mol葡萄糖。有趣的是，加入次磷酸盐，PFL的抑制剂，重组R。在光异养条件下，类球孢菌仍产生3 molH-2/mol葡萄糖，表明不仅固氮酶而且仅Fe氢化酶也产生活性H-2，它们对次磷酸盐不敏感。结果进一步表明，光异养H-2生产的FHL，除非次磷酸盐存在。因此，重组R.在光异养条件下，sphaeroides似乎是介导的FHL，铁只氢化酶和固氮酶的协同作用。重组R. sphaeroides中含有R. rubrum似乎依赖于其成熟蛋白的存在，提示在R. sphaeroides (C)2008年国际氢能协会。由爱思唯尔有限公司出版。保留所有权利。
Rhodobacter sphaeroides KCTC 12085 is a natural isolate which shows a higher ability of photoheterotrophic H-2 production compared with a laboratory strain R. sphaeroides 2.4.1. The H-2 production by R. sphaeroides is observed only under light conditions. In order to render R. sphaeroides to produce H-2 fermentatively as well, a 4.4-kb Rhodospirillum rubrum DNA encompassing a gene coding for pyruvate-formate lyase (PFL) with its putative maturation protein, and a 29.4-kb R. rubrum gene cluster including formate-hydrogen lyase (FHL) complex, its maturation proteins, a transcriptional activator for FHL, and Fe-only hydrogenase with its maturation proteins were cloned and mobilized into R. sphaeroides KCTC 12085. The recombinant R. sphaeroides evolved H-2 during dark fermentative growth. The H-2 production by the recombinant R. sphaeroides under photoheterotrophic conditions was elevated twofold to show 4 mol H-2/mol of glucose compared with 2 mol H-2/mol of glucose by its parental strain carrying empty vector. Interestingly, addition of hypophosphite, an inhibitor of PFL, to the recombinant R. sphaeroides under photoheterotrophic conditions still resulted in 3 mol H-2/mol of glucose, suggestive of active H-2 production not only by nitrogenase but also by Fe-only hydrogenase, which are insensitive to hypophosphite. The results further suggest the photoheterotrophic H-2 production by FHL unless hypophosphite is present. Thus, the H-2 production by the recombinant R. sphaeroides under photoheterotrophic conditions appears to be mediated by the concerted actions of FHL, Fe-only hydrogenase, and nitrogenase. The H-2-evolving activity by the recombinant R. sphaeroides containing Fe-only hydrogenase of R. rubrum appears to depend on the presence its maturation proteins, suggestive of lack of such proteins in R. sphaeroides. (C) 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.