Arthrobacter echigonensis介导生物氧化锰形成的机制及生物氧化锰的成分

Biogenic Manganese Oxides Component and Formation Mechanisms Catalysed by Arthrobacter echigonensis

对1株分离自锰矿矿石具有高效氧化锰活性的节杆菌(Arthrobacter echigonensis)MN1405氧化锰机制进行研究.结果表明,A.echigonensis MN1405在其生长过程中产生锰氧化活性因子和碱性物质,活性因子在细胞内合成,并分泌至菌体表面和胞外培养液中.MN1405对Mn2+的氧化作用是通过升高环境pH值和产生锰氧化活性因子共同作用的结果.虽然该菌产生锰氧化活性因子不需要Mn2+的诱导,但在培养基中加入Mn2+可以提高活性因子的产生量.MN1405产生的锰氧化活性因子对SDS、NaN3等多种酶抑制剂不敏感,而且具有较高的耐热性能.XPS和FTIR分析MN1405介导Mn2+氧化形成的生物锰氧化物,确定成分为MnOOH;SEM显示生物氧化锰的形态为絮状.

Arthrobacter echigonensis MN1405 was isolated from manganese mineral sample,with high iron and manganese oxidizing activity.The mechanisms for manganese oxidation by A.echigonensis MN1405 were studied.The results showed that A.echigonensis MN1405 would produce manganese oxidizing activity factor and alkaline material during growth,the activity factor was synthesized in the cell and then secreted into cellsurface and extracellular culture medium through cytomembrane.Strain MN1405 could oxidize Mn 2＋ by increasing pH value of extracellular environment and producing manganese oxidizing activity factor.Though it was not need the induction of Mn 2＋ for the bacterium to produce manganese oxidizing activity factor,added of Mn 2＋ into medium could increase the output of activity factor.The manganese oxidizing activity factor produced by MN1405 was insensitive to a variety of enzyme inhibitors,such as SDS,NaN3 and so on,and had higher heat resistance.The components of the biogenic manganese oxides,produced by the MN1405 catalytic on Mn 2＋ oxidation,was identified as MnOOH by XPS and FTIR.SEM showed the morphology of the manganese oxides was floccus.