Section of Integrative Biology, University of Texas at Austin, 2401 Speedway Drive C0930, Austin, TX 78712, USA.
Microb Ecol. 2011 May;61(4):821-31. doi: 10.1007/s00248-010-9793-4. Epub 2011 Jan 18.
Social insects harbor diverse assemblages of bacterial microbes, which may play a crucial role in the success or failure of biological invasions. The invasive fire ant Solenopsis invicta (Formicidae, Hymenoptera) is a model system for understanding the dynamics of invasive social insects and their biological control. However, little is known about microbes as biotic factors influencing the success or failure of ant invasions. This pilot study is the first attempt to characterize and compare microbial communities associated with the introduced S. invicta and the native Solenopsis geminata in the USA. Using 16S amplicon 454 pyrosequencing, bacterial communities of workers, brood, and soil from nest walls were compared between neighboring S. invicta and S. geminata colonies at Brackenridge Field Laboratory, Austin, Texas, with the aim of identifying potential pathogenic, commensal, or mutualistic microbial associates. Two samples of S. geminata workers showed high counts of Spiroplasma bacteria, a known pathogen or mutualist of other insects. A subsequent analysis using PCR and sequencing confirmed the presence of Spiroplasma in additional colonies of both Solenopsis species. Wolbachia was found in one alate sample of S. geminata, while one brood sample of S. invicta had a high count of Lactococcus. As expected, ant samples from both species showed much lower microbial diversity than the surrounding soil. Both ant species had similar overall bacterial diversities, although little overlap in specific microbes. To properly characterize a single bacterial community associated with a Solenopsis ant sample, rarefaction analyses indicate that it is necessary to obtain 5,000-10,000 sequences. Overall, 16S amplicon 454 pyrosequencing appears to be a cost-effective approach to screen whole microbial diversity associated with invasive ant species.
社会性昆虫体内栖息着多样的细菌微生物群落，这些微生物可能在生物入侵的成败中起着至关重要的作用。入侵红火蚁 Solenopsis invicta（膜翅目，蚁科）是理解入侵社会性昆虫及其生物防治动态的模式生物系统。然而，人们对作为影响蚂蚁入侵成败的生物因素的微生物知之甚少。本研究旨在首次对美国引入的红火蚁 S. invicta 和本地的 S. geminata 相关的微生物群落进行特征描述和比较，这是一项初步尝试。利用 16S 扩增子 454 焦磷酸测序技术，比较了德克萨斯州奥斯汀 Brackenridge 野外实验室相邻的红火蚁和本地的 S. geminata 工蚁、幼虫和巢壁土壤样本中的细菌群落，目的是鉴定潜在的致病、共生或互惠共生的微生物伴生物种。两个 S. geminata 工蚁样本显示出高数量的螺旋体细菌，这是其他昆虫的一种已知病原体或共生体。随后的 PCR 和测序分析证实了这两种红火蚁物种的其他群体中存在螺旋体。在 S. geminata 的一个有翅个体样本中发现了沃尔巴克氏体，而在 S. invicta 的一个幼虫样本中发现了高数量的乳球菌。正如预期的那样，来自两种蚂蚁的样本的微生物多样性明显低于周围土壤。两种蚂蚁物种的总体细菌多样性相似，尽管特定微生物的重叠很少。为了正确描述与红火蚁样本相关的单一细菌群落，稀疏分析表明，有必要获得 5000-10000 个序列。总体而言，16S 扩增子 454 焦磷酸测序似乎是一种具有成本效益的方法，可以筛选与入侵蚂蚁物种相关的整个微生物多样性。
