Bio-Protection Research Centre, Lincoln University, Lincoln, New Zealand.
School of Fundamental Sciences, Massey University, Palmerston North, New Zealand.
Arch Insect Biochem Physiol. 2020 Dec;105(4):e21754. doi: 10.1002/arch.21754. Epub 2020 Oct 30.
Species in the fungal genus Beauveria are pathogens of invertebrates and have been commonly used as the active agent in biopesticides. After many decades with few species described, recent molecular approaches to classification have led to over 25 species now delimited. Little attention has been given to the mitochondrial genomes of Beauveria but better understanding may led to insights into the nature of species and evolution in this important genus. In this study, we sequenced the mitochondrial genomes of four new strains belonging to Beauveria bassiana, Beauveria caledonica and Beauveria malawiensis, and compared them to existing mitochondrial sequences of related fungi. The mitochondrial genomes of Beauveria ranged widely from 28,806 to 44,135 base pairs, with intron insertions accounting for most size variation and up to 39% (B. malawiensis) of the mitochondrial length due to introns in genes. Gene order of the common mitochondrial genes did not vary among the Beauveria sequences, but variation was observed in the number of transfer ribonucleic acid genes. Although phylogenetic analysis using whole mitochondrial genomes showed, unsurprisingly, that B. bassiana isolates were the most closely related to each other, mitochondrial codon usage suggested that some B. bassiana isolates were more similar to B. malawiensis and B. caledonica than the other B. bassiana isolates analyzed.
被毛壳菌属真菌侵染的物种是无脊椎动物的病原体，并且通常被用作生物农药中的有效成分。经过几十年的描述，最近的分子分类方法导致现在已经确定了 25 个以上的物种。毛壳菌的线粒体基因组很少受到关注，但更好的理解可能会深入了解这个重要属中物种的本质和进化。在这项研究中，我们对属于球孢白僵菌、新喀里多尼亚白僵菌和马拉维白僵菌的四个新菌株的线粒体基因组进行了测序，并将其与相关真菌的现有线粒体序列进行了比较。毛壳菌的线粒体基因组大小范围很广，从 28806 到 44135 个碱基对，由于基因中的内含子，大多数大小变化是由内含子插入引起的，占线粒体长度的 39%（B. malawiensis）。常见线粒体基因的基因排列在白僵菌序列之间没有变化，但转移核糖核酸基因的数量存在变化。虽然使用整个线粒体基因组进行的系统发育分析表明，不出所料，B. bassiana 分离株彼此之间最密切相关，但线粒体密码子使用表明，一些 B. bassiana 分离株与 B. malawiensis 和 B. caledonica 比其他分析的 B. bassiana 分离株更相似。
