湖南益阳黑茶中桔青霉线粒体全基因组序列测定及分析

对黑茶中分离的一株桔青霉线粒体基因序列进行测定与分析,并探究其与近缘种微生物的系统发育关系。结果表明,桔青霉线粒体基因组是一条全长27β537βbp的环状DNA分子,共编码42个基因（15个蛋白质编码基因,2个rRNA,24个tRNA以及1个独立的ORF）,基因组碱基构成为：A（36.17%）、T（37.06%）、C（11.82%）、G（14.95%）。15个蛋白质编码基因均采用典型的ATG作为起始密码子、TAA或TAG作为终止密码子,基因排列顺序与已报道的青霉属物种相似,在进化上较为保守。蛋白质编码基因编码频率较高的氨基酸分别为Leu、Ile、Ser和Phe;RSCU频率最高的4个密码子依次是UUA、AUA、UUU和GGU。24个tRNA基因存在30处G-U错配,均可形成典型三叶草结构。系统发育分析结果表明,桔青霉分类地位上关系最密切是Penicillium ShG4C,其次是Penicillium polonicum与Penicillium nordicum。

Sequencing and Analysis of the Complete Mitochondrial Genome of Penicillium Citrinum in Hunan Yiyang Dark Tea

In this study, the mitochondrial genome sequence of a strain of Penicillium citrinum isolated from dark tea was determined and analyzed, and its phylogenetic relationship with the closely related microorganisms was explored. The result shows that the mitochondrial genome of Penicillium citrinum is a circular DNA molecule with a length of 27β537βbp, which encodes 42 genes. The genome bases are composed of A (36.17%), T (37.06%), C (11.82%) and G (14.95%). All the 15 protein-coding genes use typical ATG as the start codon, TAA or TAG as the stop codon. Its gene sequences are similar to those of the reported Penicillium species and are conserved in evolution. The highly occurred amino acids in the protein-coding genes are Leu, Ile, Ser and Phe. The top 4 codons with the high RSCU frequency are UUA, AUA, UUU and GGU, respectively. There are 30 G-U mismatches in 24 tRNA genes, all of which could form typical cloverleaf structure. Phylogenetic analysis shows that the most closely related taxonomic status of Penicillium citrinum is Penicillium ShG4C, followed by Penicillium polonicum and Penicillium nordicum.