MANGANESE OXIDATION BY LEPTOTHRIX-DISCOPHORA
MANGANESE OXIDATION BY LEPTOTHRIX-DISCOPHORA
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DOI：
10.1128/jb.169.2.489-494.1987
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发表时间：
1987-02-01
影响因子：
3.2
通讯作者：
DEVRIND, JPM
中科院分区：
文献类型：
--
作者：
BOOGERD, FC;DEVRIND, JPM
Leptothrix discophora SS1 细胞在分批培养过程中向培养基中释放 Mn2+ 氧化因子。当培养基用 HEPES（N-2-羟乙基哌嗪-N''-2-乙磺酸）缓冲至 pH 7.5 时，锰的氧化效果最佳。该菌株先前生长的培养基中的锰氧化活性对热、磷酸盐、Tris、NaN3、HgCl2 NaCl、十二烷基硫酸钠和链霉酶敏感；每生成 1 mol MnO2，消耗 0.5 mol O2。在Mn2+氧化过程中，质子被释放。采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳，在废培养基中检测到两条含蛋白质条带。一条带的表观分子量为 110,000，主要是 Mn2+ 氧化活性。第二种产物 (Mr 85,000) 仅在某些情况下才被检测到，可能代表 110,000-Mr 蛋白的蛋白水解分解部分。 Mn2+ 氧化因子与废培养基中形成的 MnO2 聚集体有关。用抗坏血酸溶解该 MnO2 后，可以恢复 Mn2+ 氧化活性。
Cells of Leptothrix discophora SS1 released Mn2+-oxidizing factors into the medium during growth in batch culture. Manganese was optimally oxidized when the medium was buffered with HEPES (N-2-hydroxyethylpiperazine-N''-2-ethanesulfonic acid) at pH 7.5. Manganese-oxidizing activity in the culture medium in which this strain had been grown previously was sensitive to heat, phosphate, Tris, NaN3, HgCl2 NaCl, sodium dodecyl sulfate and pronase; 0.5 mol of O2 was consumed per mol of MnO2 formed. During Mn2+ oxidation, protons were liberated. With sodium dodecyl sulfate-polyacrylamide gel electrophoresis, two protein-containing bands were detected in the spent culture medium. One band had an apparent molecular weight of 110,000 and was predominant in Mn2+-oxidizing activity. The second product (Mr 85,000) was only detected in some cases and probably represents a proteolytic breakdown moiety of the 110,000-Mr protein. The Mn2+-oxidizing factors were associated with the MnO2 aggregates that had been formed in spent culture medium. After solubilization of this MnO2 with ascorbate, Mn2+-oxidizing activity could be recovered.