In this work, C. testosteroni JLU460ET isolated from animal waste was confirmed to have great degradation capability for 17β-estradiol and testosterone. This bacterium could degrade nearly 90% of 17β-estradiol (5 mg L⁻¹) in 4 days and transform it into estrone for further degradation. One hundred percent testosterone (144 mg L⁻¹) could be completely degraded after 9 h of incubation. This is the first report of C. testosteroni strains with the ability to degrade both estrogens and testosterone. The whole genome sequence of C. testosteroni JLU460ET was obtained and annotated, containing one chromosome (5,497,097 bp) with 61.37% GC content. A total of 4805 protein-coding genes and 134 RNA genes (including 29 rRNA genes, 102 tRNA genes and three ncRNA genes) were identified. Furthermore, the complete genome sequence of C. testosteroni JLU460ET was compared with four other C. testosteroni strains. Altogether, these five C. testosteroni strains contain 3508 core genes and 7616 pan genes. A steroid degradation pathway including 11 steroid degradation genes exists in core genes of five C. testosteroni strains. Twenty-two steroid degradation genes were found in the C. testosteroni JLU460ET genome, which has the most reported steroid degradation genes among the five C. testosteroni genomes. Further functional genomic analysis identified a gene cluster responsible for testosterone degradation in C. testosteroni JLU460ET, as well as a gene encoding 17β-HSD, the key enzyme for transforming 17β-estradiol into estrone. This work could enrich the genome sources of steroid-degrading strains and promote the study of steroid-degradation mechanism in bacteria.

在这项工作中，证实了从动物粪便中分离出的C. testosteroni JLU460ET 对 17β-雌二醇和睾酮具有很强的降解能力。这种细菌可以在4天内降解近90%的17β-雌二醇(5 mg L ^-1 )，并将其转化为雌酮进一步降解。100% 的睾酮（144 mg L ^-1）可在孵育 9 小时后完全降解。这是具有降解雌激素和睾酮能力的C. testosteroni菌株的第一份报告。C. testosteroni的全基因组序列获得并注释了JLU460ET，包含一条染色体（5,497,097 bp），GC含量为61.37%。共鉴定出4805个蛋白质编码基因和134个RNA基因（包括29个rRNA基因、102个tRNA基因和3个ncRNA基因）。此外，将C. testosteroni JLU460ET的完整基因组序列与其他四种C. testosteroni菌株进行了比较。这 5 个C. testosteroni菌株总共包含 3508 个核心基因和 7616 个泛基因。5个C. testosteroni菌株的核心基因中存在一个包括11个类固醇降解基因的类固醇降解途径。在C. testosteroni中发现了 22 个类固醇降解基因JLU460ET 基因组，在五个C. testosteroni基因组中具有最多报道的类固醇降解基因。进一步的功能基因组分析确定了一个负责睾酮梭菌 JLU460ET 中睾酮降解的基因簇，以及一个编码 17β-HSD 的基因，这是将 17β-雌二醇转化为雌酮的关键酶。这项工作可以丰富类固醇降解菌株的基因组来源，促进细菌类固醇降解机制的研究。