A PKS gene, pks-1, is involved in chaetoglobosin biosynthesis, pigmentation and sporulation in Chaetomium globosum  

作　　者：HU Yang HAO XiaoRan LOU Jing ZHANG Ping PAN Jiao ZHU XuDong 

机构地区：[1]State Key Program of Microbiology and Department of Microbiology, College of Life Sciences Nankai University, Tianjin 300071, China

出　　处：《Science China(Life Sciences)》2012年第12期1100-1108,共9页中国科学（生命科学英文版）

基　　金：the National Natural Science Foundation of China (Grant No. 30970084);the National Basic Research Program of China (Grant No. 2007CB707801)

摘　　要：Chaetomium globosum is one of the most common fungi in nature. It is best known for producing chaetoglobosins; however, the molecular basis of chaetoglobosin biosynthesis is poorly understood in this fungus. In this study, we utilized RNA inter- ference （RNAi） to characterize a polyketide synthase gene, pks-1, in C. globosum that is involved in the production of chaeto- globosin A. When pks-1 was knocked down by RNAi, the production of chaetoglobosin A dramatically decreased. Knock-down mutants also displayed a pigment-deficient phenotype. These results suggest that the two polyketides, melanin and chaetoglobosin, are likely to share common biosynthetic steps. Most importantly, we found that pks-I also plays a critical role in sporulation. The silenced mutants ofpks-1 lost the ability to produce spores. We propose that polyketides may modulate cellular development via an unidentified action. We also suggest that C. globosum pks-1 is unique because of its triple role in melanin formation, chaetoglobosin biosynthesis and sporulation. This work may shed light on chaetoglobosin biosynthesis and indicates a relationship between secondary metabolism and fungal morphogenesis.Chaetomium globosum is one of the most common fungi in nature. It is best known for producing chaetoglobosins; however, the molecular basis of chaetoglobosin biosynthesis is poorly understood in this fungus. In this study, we utilized RNA interference (RNAi) to characterize a polyketide synthase gene, pks-1, in C. globosum that is involved in the production of chaetoglobosin A. When pks-1 was knocked down by RNAi, the production of chaetoglobosin A dramatically decreased. Knock-down mutants also displayed a pigment-deficient phenotype. These results suggest that the two polyketides, melanin and chaetoglobosin, are likely to share common biosynthetic steps. Most importantly, we found that pks-1 also plays a critical role in sporulation. The silenced mutants of pks-1 lost the ability to produce spores. We propose that polyketides may modulate cellular development via an unidentified action. We also suggest that C. globosum pks-1 is unique because of its triple role in melanin formation, chaetoglobosin biosynthesis and sporulation. This work may shed light on chaetoglobosin biosynthesis and indicates a relationship between secondary metabolism and fungal morphogenesis.

关 键 词：polyketide synthase （PKS） MELANIN chaetoglobosin A Chaetomium globosum 

分 类 号：Q949.323.4[生物学—植物学] TQ465.5[化学工程—制药化工]