Annous B A, Blaschek H P
Department of Food Science, University of Illinois, Urbana 61801.
Appl Environ Microbiol. 1990 Aug;56(8):2559-61. doi: 10.1128/aem.56.8.2559-2561.1990.
Amylolytic activity was primarily cell associated when Clostridium acetobutylicum was grown on glucose or maltose and primarily extracellular when grown on dextrin or starch. Total amylolytic activity decreased with increasing glucose concentration. When this microorganism was grown in P2 medium containing starch, the intracellular amylolytic activity was 90% membrane bound and 10% cytoplasmic in nature. The addition of 1% glucose to 2% starch-based P2 medium at different stages of growth indicated that this carbohydrate repressed the synthesis of C. acetobutylicum amylolytic enzymes at the level of transcription.
当丙酮丁醇梭菌在葡萄糖或麦芽糖上生长时，淀粉酶活性主要与细胞相关；而在糊精或淀粉上生长时，淀粉酶活性主要存在于细胞外。总淀粉酶活性随葡萄糖浓度的增加而降低。当这种微生物在含有淀粉的P2培养基中生长时，细胞内的淀粉酶活性90%与膜结合，10%存在于细胞质中。在生长的不同阶段，向基于2%淀粉的P2培养基中添加1%葡萄糖，结果表明这种碳水化合物在转录水平上抑制了丙酮丁醇梭菌淀粉酶的合成。
