Department of Molecular Biophysics and Biochemistry, Yale University New Haven, CT 06511, USA.
Department of Genetics, Harvard Medical School, Boston, MA 02115, USA.
Microbiology (Reading). 2010 Dec;156(Pt 12):3814-3829. doi: 10.1099/mic.0.041327-0. Epub 2010 Aug 12.
The Patagonian fungal endophyte NRRL 50072 is reported to produce a variety of medium-chain and highly branched volatile organic compounds (VOCs) that have been highlighted for their potential as fuel alternatives and are collectively termed myco-diesel. To assess the novelty of this observation, we determined the extent to which ten closely related Ascocoryne strains from commercial culture collections possess similar VOC production capability. DNA sequencing established a high genetic similarity between NRRL 50072 and each Ascocoryne isolate, consistent with its reassignment as Ascocoryne sarcoides. The Ascocoryne strains did not produce highly branched medium-chain-length alkanes, and efforts to reproduce the branched alkane production of NRRL 50072 were unsuccessful. However, we confirmed the production of 30 other products and expanded the list of VOCs for NRRL 50072 and members of the genus Ascocoryne. VOCs detected from the cultures consisted of short- and medium-chain alkenes, ketones, esters and alcohols and several sesquiterpenes. Ascocoryne strains NRRL 50072 and CBS 309.71 produced a more diverse range of volatiles than the other isolates tested. CBS 309.71 also showed enhanced production compared with other strains when grown on cellulose agar. Collectively, the members of the genus Ascocoryne demonstrated production of over 100 individual compounds, with a third of the short- and medium-chain compounds also produced when cultures were grown on a cellulose substrate. This comparative production analysis could facilitate future studies to identify and manipulate the biosynthetic machinery responsible for production of individual VOCs, including several that have a potential application as biofuels.
巴塔哥尼亚真菌内生菌 NRRL 50072 据报道可产生多种中链和高度支化的挥发性有机化合物（VOC），这些化合物因其作为燃料替代品的潜力而备受关注，统称为真菌柴油。为了评估这一观察结果的新颖性，我们确定了十个来自商业培养物收集的密切相关的 Ascocoryne 菌株在多大程度上具有类似的 VOC 产生能力。DNA 测序表明 NRRL 50072 与每个 Ascocoryne 分离株之间具有高度的遗传相似性，这与其被重新分配为 Ascocoryne sarcoides 一致。Ascocoryne 菌株不产生高度支化的中链长度烷烃，并且复制 NRRL 50072 的支化烷烃生产的努力均未成功。然而，我们确认了 30 种其他产物的产生，并扩大了 NRRL 50072 和 Ascocoryne 属成员的 VOC 清单。从培养物中检测到的 VOC 包括短链和中链烯烃、酮、酯和醇以及几种倍半萜烯。NRRL 50072 和 CBS 309.71 菌株比其他测试的分离株产生了更多种类的挥发性物质。当在纤维素琼脂上生长时，CBS 309.71 与其他菌株相比也显示出增强的生产能力。总体而言，Ascocoryne 属的成员表现出产生超过 100 种化合物的能力，其中当在纤维素底物上培养时，也产生了三分之一的短链和中链化合物。这种比较生产分析可以促进未来的研究，以鉴定和操纵负责产生单个 VOC 的生物合成机制，包括几种可能作为生物燃料应用的 VOC。
