Jiang Mingfeng, Li Xiao, Zhang Liang, Feng Hong, Zhang Yizheng
College of Life Science, Sichuan University, Chengdu 610064, P. R. China.
J Microbiol. 2009 Jun;47(3):308-18. doi: 10.1007/s12275-008-0275-z. Epub 2009 Jun 26.
In order to identify the secondary metabolism-related genes of Phanerochaete chrysosporium growing under pure O2 and nitrogen-limited conditions, 2322 ESTs fragments originated from two suppression-subtractive libraries were analyzed using the cDNA microarray technique. Ten significantly upregulated and 22 significantly downregulated genes were identified in the 72 h cultured mycelia RNA samples (secondary metabolism). According to qPCR, 16 out of the 32 genes were expressed differently in secondary metabolism. Transcripts of secondary metabolism up-regulation genes exhibited homologies to aryl-alcohol dehydrogenase (SShl554), ABC transporter gene (SSH624), chitinase (SSH963), heat shock protein (SSH1193), catalase (SSH317), cytochrome P450 (SSH331), glucosamine-6-phosphate isomerase (SSH611), and alkyl hydroperoxide reductase (SSH362) genes. Ninety-three genes could be classified by Eukaryotic Orthologous Groups (KOG). Among the genes assigned a function, gene expression patterns were different in both secondary metabolism and primary metabolism. In the group of "Cellular Processes and Signaling," most of the genes were from the primary metabolism library. On the other hand, genes from the secondary metabolism library were found mainly in the "Information Storage" and "Processing and Poorly Characterized" groups. Based on the KOG functional assignments, six genes belong to the ubiquitin system, and all of them were from primary metabolism phase. The presence of the H2O2-relevant genes suggested that parts of the genes expressed in 72 h might be involved in the ligninolytic process during secondary metabolism of P. chrysosporium.
为了鉴定在纯氧和氮限制条件下生长的黄孢原毛平革菌中与次生代谢相关的基因，利用cDNA微阵列技术对来自两个抑制消减文库的2322个EST片段进行了分析。在培养72小时的菌丝体RNA样品（次生代谢）中鉴定出10个显著上调和22个显著下调的基因。根据定量PCR，32个基因中有16个在次生代谢中表达不同。次生代谢上调基因的转录本与芳基醇脱氢酶（SShl554）、ABC转运蛋白基因（SSH624）、几丁质酶（SSH963）、热休克蛋白（SSH1193）、过氧化氢酶（SSH317）、细胞色素P450（SSH331）、葡糖胺-6-磷酸异构酶（SSH611）和烷基过氧化氢还原酶（SSH362）基因具有同源性。93个基因可通过真核直系同源组（KOG）进行分类。在已赋予功能的基因中，基因表达模式在次生代谢和初级代谢中均有所不同。在“细胞过程和信号传导”组中，大多数基因来自初级代谢文库。另一方面次生代谢文库中的基因主要存在于“信息存储”和“加工及特征不明确”组中。根据KOG功能分配，六个基因属于泛素系统，并且它们全部来自初级代谢阶段。与H2O2相关的基因的存在表明，在72小时表达的部分基因可能参与了黄孢原毛平革菌次生代谢过程中的木质素分解过程。
