Mutational profiling of Scheffersomyces stipitis (previously known as Pichia stipitis Shi21). Scheffersomyces stipitis Shi21

Scheffersomyces stipitis (synonym: Pichia stipitis) strain Shi21 is derived from reference strain CBS 6054. Shi21 has been subjected to chemical mutagenesis, phenotypic selection, genetic engineering and adaptive evolution in order to develop strains improved for ethanol production. Chemical mutagenesis and selection resulted in small improvements in ethanol production attributable in part to carbon catabolite derepression. Disruption of CYC1 (Cyctochrome c, isoform 1) to create strain Shi21 increased the specific ethanol production rate by 50% and the ethanol yield by 10%

嗜鞣管囊酵母（Scheffersomyces stipitis，同义名：毕赤酵母Pichia stipitis）菌株Shi21衍生自参考菌株CBS 6054。为培育乙醇生产性能优化的菌株，研究人员对Shi21开展了化学诱变、表型筛选、基因工程改造及适应性进化实验。化学诱变与筛选可使乙醇生产性能获得小幅提升，该效果部分源于碳分解代谢物阻遏解除（carbon catabolite derepression）。敲除细胞色素c同工型1基因CYC1（Cytochrome c, isoform 1）以构建Shi21菌株的操作，可使乙醇比生产速率提升50%，乙醇得率提升10%。