Isolation, production, purification and characterization of an organic-solvent-thermostable alkalophilic cellulase from Bacillus vallismortis RG-07.
Isolation, production, purification and characterization of an organic-solvent-thermostable alkalophilic cellulase from Bacillus vallismortis RG-07.
复制标题
DOI：
10.1186/s12896-015-0129-9
复制
发表时间：
2015-03-19
影响因子：
3.5
通讯作者：
Tiwari S
中科院分区：
文献类型：
--
作者：
Gaur R;Tiwari S
对化石燃料稀缺、绿色家用气体排放和化石燃料不完全燃烧造成的空气污染的日益关注也导致越来越多地关注使用纤维素酶进行木质纤维素材料的酶促水解以产生生物乙醇。从天然资源中筛选出一株具有耐热性的纤维素酶产生菌，并对其进行分离纯化和酶学性质研究。纯化的酶可用于生物乙醇生产以及工业开发（在我们的下一个研究中讨论）。这是首次从土壤样品中分离到耐高温溶剂的纤维素酶产生菌。经16 S rDNA序列分析，该菌株被鉴定为Bacillus vallismortis RG-07。芽孢杆菌vallismortis RG-07报道了从用作农业废物碳源的甘蔗装袋酶（4105 U ml-1）产生最大纤维素酶。经硫酸铵沉淀、离子交换层析和凝胶过滤层析对纤维素酶进行了纯化，总回收率为28.8%。经SDS-PAGE和酶活力凝胶分析表明，纯化的纤维素酶分子量约为80 kDa。酶活的最适温度和pH值分别为65 ℃和7.0，即使在95 ℃和9.0下，酶活仍分别保持95%和75%。在有机溶剂（30%）正十二烷、异辛烷、正癸烷、二甲苯、甲苯、正己烷、正丁醇和环己烷的存在下，长时间孵育（7天）后，酶活性增强。Ca ~（2+）、巯基乙醇、Tween-60和次氯酸钠对酶活性有促进作用，而Hg对酶活性有强烈的抑制作用。纯化酶的动力学分析显示Km和Vmax分别为1.923 mg ml−1和769.230 μg ml−1 min−1。该菌株具有耐溶剂、耐高温、嗜碱性等独特的性质，是目前生物质转化为燃料和其他工业过程的潜在候选者。本文的在线版本（doi：10.1186/s12896-015-0129-9）包含补充材料，可供授权用户使用。
The rising concerns about the scarcity of fossil fuels, the emission of green house gasses and air pollution by incomplete combustion of fossil fuel have also resulted in an increasing focus on the use of cellulases to perform enzymatic hydrolysis of the lignocellulosic materials for the generation of bioethanol. The aim of this study was to isolate a potential thermo-solvent tolerant cellulase producing bacterium from natural resources, and then applied for purification and characterization. The purified enzyme was to be accessible for the bioethanol production as well as industrial exploitation (discuss in our next study). It is the first instance when thermo-solvent tolerant cellulase producing bacterium was isolated from soil sample. The culture was identified as Bacillus vallismortis RG-07 by 16S rDNA sequence analysis. Bacillus vallismortis RG-07 reported maximum cellulase production from sugarcane baggase (4105 U ml−1) used as agro-waste carbon source. The cellulase enzyme produced by the Bacillus sp. was purified by (NH4)2SO4 precipitation, ion exchange and gel filtration chromatography, with overall recovery of 28.8%. The molecular weight of purified cellulase was 80 kDa as revealed by SDS-PAGE and activity gel analysis. The optimum temperature and pH for enzyme activity was determined as 65°C and 7.0 and it retained 95 and 75% of activity even at 95°C, and 9.0 respectively. The enzyme activity was enhanced in the presence of organic solvents (30%) n-dodecane, iso-octane, n-decane, xylene, toluene, n-haxane, n-butanol, and cyclohexane, after prolonged incubation (7 days). The enzyme activity was also stimulated by Ca2+, mercaptoethanol, Tween-60, and Sodium hypochloride whereas strongly inhibited by Hg. Kinetic analysis of purified enzyme showed the Km and Vmax to be 1.923 mg ml−1 and 769.230 μg ml−1 min−1, respectively. The unique property of solvent-thermostable-alkalophilic, nature proves the potential candidature of this isolate for current mainstream biomass conversion into fuel and other industrial process. The online version of this article (doi:10.1186/s12896-015-0129-9) contains supplementary material, which is available to authorized users.
登录
查看更多内容
影响因子：
--
作者：
Sadhu S;Saha P;Sen SK;Mayilraj S;Maiti TK
通讯作者：
Maiti TK
影响因子：
9.7
作者：
Mayende, Lungisa;Wilhelmi, Brendan S.;Pletschke, Brett I.
通讯作者：
Pletschke, Brett I.
影响因子：
3.2
作者：
Jo, Kang-Ik;Lee, You-Jung;Lee, Jin-Woo
通讯作者：
Lee, Jin-Woo
影响因子：
15
作者：
Lineweaver, H;Burk, D
通讯作者：
Burk, D
DOI：
10.1007/s10295-012-1120-2
发表时间：
2012-08-01
影响因子：
3.4
作者：
Li, Xin;Yu, Hui-Ying
通讯作者：
Yu, Hui-Ying