Strain improvement of Acremonium cellulolyticus for cellulase production by mutation
Strain improvement of Acremonium cellulolyticus for cellulase production by mutation
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DOI：
10.1016/j.jbiosc.2008.11.022
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发表时间：
2009-03-01
影响因子：
2.8
通讯作者：
Sawayama, Shigeki
中科院分区：
文献类型：
--
作者：
Fang, Xu;Yano, Shinichi;Sawayama, Shigeki
为了寻找高效产纤维素酶的菌株，利用紫外线和N-甲基-N‘-硝基-N-亚硝基(NTG)诱变，筛选到一株高效产纤维素酶的菌株CF-2612。菌株CF-2612的滤纸酶活力(17.8U/ml)高于亲本菌株C-1(12.3U/ml)。菌株CF-2612的可溶性蛋白产量和β-葡萄糖苷酶活性也显著提高。在30℃的2-L罐中，添加5%Solka Floc分批培养的CF2612的纤维素酶活、纤维素酶产量和产糖量分别达到18.0U/ml、150.0 fPU/L/h和360.0 fPU/g碳水化合物，而使用Solka Floc分批补料培养时，这些值分别达到34.6U/ml、240.3 fPU/L/h和346.0 fPU/g糖。结果表明，与市售纤维素酶GC-220相比，菌株CF-2612处理的桉木能释放更多的水解糖。这归因于菌株CF-2612具有较高的β-葡萄糖苷酶/FP酶活力比值。在分批培养中，提出了三个可区分的阶段，即第一次或第二次菌丝生长时期和菌丝碎裂时期。(C)2009年，日本生物技术学会。版权所有。
In the search for an efficient producer of cellulolytic enzymes, Acremonium cellulolyticus strain C-1 was subjected to mutagenesis using UV-irradiation and N-methyl-N'nitro-N-nitrosoguanidine (NTG) and strain CF-2612 was isolated. Strain CF-2612 exhibited higher filter paperase (FPase) activities (17.8 U/ml) than the parent strain C-1 (12.3 U/ml). Soluble protein production and beta-glucosidase activity from strain CF-2612 were also significantly improved. FPase activity, cellulase productivity and yield of CF-2612 using batch culture with 5% Solka Floc in a 2-l jar fermentor at 30 degrees C reached 18.0 U/ml, 150.0 FPU/l/h and 360.0 FPU/g carbohydrate, respectively; when fed-batch culture was used with Solka Floc, these values reached 34.6 U/ml, 240.3 FPU/l/h and 346.0 FPU/g carbohydrate, respectively. It was observed that more hydrolyzed glucose was released from pretreated eucalyptus with the enzyme of strain CF-2612, compared with that of the commercial cellulase GC-220. This result was attributed to the higher ratio of beta-glucosidase/FPase activity of strain CF-2612. Three distinguishable phases including the periods of primary or second mycelial growth and mycelial fragmentation were proposed in batch culture by A. cellulolyticus. (C) 2009, The Society for Biotechnology, Japan. All rights reserved.