The phylum Firmicutes comprises seven classes where most species are either aerobic or anaerobic endospore former. Inside Firmicutes, species allocated in the genus Bacillus and related genera are collectively named aerobic endospore-forming bacteria (AEFB), and the soil is their major reservoir. AEFB have great importance in health, agriculture, and biotechnology although the more studied species are Bacillus subtilis and the human pathogens Bacillus cereus and Bacillus anthracis. AEFB have great importance in health, agriculture, and biotechnology; although the knowledge about these organisms is based on few species, notably, Bacillus subtilis, Bacillus cereus, and Bacillus anthracis. In this work, we generated partial 16S rRNA gene sequences of both strands of 192 AEFB strains isolated from soils of Distrito Federal, Brazil (SDF strains). The resulting consensus sequences were used to obtain taxonomic assignment and establish the phylogenetic relationships among these strains. Through this approach, we could observe that classified SDF strains were distributed among genera Bacillus (169 strains; 88.02%), Paenibacillus (11; 5.73%), Lysinibacillus (6; 3.13%), Brevibacillus (4; 2.08%), Terribacillus (1; 0.52%), and Rummeliibacillus (1; 0.52%). Phylogenetic trees revealed these 192 SDF strains can be segregated into eight groups spanning families Bacillaceae and Paenibacillaceae belonging to the order Bacillales. To expand the knowledge about the diversity of these SDF strains, further studies regarding characterization with different methodologies are underway.

中文翻译：

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从巴西土壤中分离出好氧孢子的芽孢杆菌的系统发生多样性。

Firmicutes门包括七个类别，其中大多数物种是有氧或无氧内生孢子形成物。在Firmicutes内部，芽孢杆菌属和相关属中分配的物种统称为好氧内生孢子形成细菌（AEFB），土壤是它们的主要储藏库。尽管研究较多的物种是枯草芽孢杆菌和人类病原体蜡状芽孢杆菌和炭疽芽孢杆菌，但AEBF在健康，农业和生物技术中具有重要意义。AEFB在健康，农业和生物技术中具有重要意义；尽管有关这些生物的知识基于很少的物种，尤其是枯草芽孢杆菌，蜡状芽孢杆菌和炭疽芽孢杆菌。在这项工作中，我们生成了从巴西Distrito Federal，土壤（SDF菌株）中分离出的192个AEFB菌株的两条链的部分16S rRNA基因序列。所得的共有序列用于获得分类学分配并建立这些菌株之间的系统发育关系。通过这种方法，我们可以观察到分类的SDF菌株分布在芽孢杆菌属（169株; 88.02％），Paenibacillus（11; 5.73％），Lysinibacillus（6; 3.13％），Brevibacillus（4; 2.08％），Terribacillus（ 1； 0.52％）和Rummeliibacillus（1； 0.52％）。系统发育树显示这192个SDF菌株可以分为8个类，它们属于芽孢杆菌科的芽孢杆菌科和芽孢杆菌科。为了扩展有关这些SDF菌株多样性的知识，正在进行有关使用不同方法进行表征的进一步研究。